/apps/tools/twndel: thingies

Reviewed-on: http://tochie.space:3001/veclavtalica/townengine/pulls/2

.gitignore

@@ -2,13 +2,17 @@
 *
 !*.*
 !*/
+!bin/*
 !Makefile
+!LICENSE
+!COPYING
 
 **/*.exe
 **/*.html
 **/*.js
 **/*.wasm
 **/*.wasm.map
+**/*.data
 **/*.so
 **/*.dll
 **/*.7z

CMakeLists.txt

@@ -5,6 +5,8 @@ project(townengine LANGUAGES C)
 set(CMAKE_MESSAGE_LOG_LEVEL "WARNING")
 set(CMAKE_INSTALL_MESSAGE NEVER)
 
+# TODO: test whether webgl 1 is good enough.
+
 # SDL dependencies
 # for whatever reason Emscripten has SDL2 config, but not actual SDL2 port by default
 if(NOT EMSCRIPTEN)
@@ -26,19 +28,19 @@ set(TWN_TARGET townengine CACHE INTERNAL "")
 set(TWN_ROOT_DIR ${CMAKE_CURRENT_SOURCE_DIR} CACHE INTERNAL "")
 
 # feature configuration, set them with -DFEATURE=ON/OFF in cli
-option(TWN_FEATURE_DYNLIB_GAME  "Enable dynamic library loading support" ON)
+option(TWN_USE_AMALGAM "Enable use of twn_amalgam.c as a single compilation unit" ON)
-option(TWN_FEATURE_PUSH_AUDIO  "Enable frame based audio push for easy realtime audio" ON)
+option(TWN_FEATURE_DYNLIB_GAME "Enable dynamic library loading support" ON)
-option(TWN_USE_AMALGAM  "Enable use of twn_amalgam.c as a single compilation unit" ON)
+set(TWN_OUT_DIR ${CMAKE_SOURCE_DIR} CACHE PATH "Artifact destination")
 
-# todo: figure out how to compile for dynamic linking instead
+# todo: figure out how to compile for dynamic linking instead?
-if(EMSCRIPTEN)
+if(HAIKU OR EMSCRIPTEN)
         if(TWN_FEATURE_DYNLIB_GAME)
                 message(WARNING "TWN_FEATURE_DYNLIB_GAME is set, but not supported - it is turned off")
                 set(TWN_FEATURE_DYNLIB_GAME OFF CACHE INTERNAL "")
         endif()
 endif()
 
-if(HAIKU)
+if(HAIKU OR EMSCRIPTEN)
         if(TWN_SANITIZE)
                 message(WARNING "TWN_SANITIZE is set, but not supported - it is turned off")
                 set(TWN_SANITIZE OFF CACHE INTERNAL "")
@@ -64,11 +66,7 @@ set(PHYSFS_ARCHIVE_7Z OFF CACHE INTERNAL "")
 add_subdirectory(third-party/physfs ${CMAKE_CURRENT_BINARY_DIR}/third-party/physfs SYSTEM)
 add_subdirectory(third-party/libxm ${CMAKE_CURRENT_BINARY_DIR}/third-party/libxm SYSTEM)
 
-if(EMSCRIPTEN)
+set(TWN_RENDERING_API OPENGL_15)
-        set(TWN_RENDERING_API WEBGL1)
-else()
-        set(TWN_RENDERING_API OPENGL_15)
-endif()
 
 if(TWN_RENDERING_API MATCHES OPENGL_15)
         set(SYSTEM_SOURCE_FILES ${SYSTEM_SOURCE_FILES}
@@ -84,7 +82,6 @@ set(TWN_THIRD_PARTY_SOURCE_FILES
 
 set(TWN_NONOPT_SOURCE_FILES
         src/twn_stb.c
-        src/twn_main.c
 
         src/twn_context.c       include/twn_context.h
         src/twn_audio.c         include/twn_audio.h
@@ -97,6 +94,7 @@ set(TWN_NONOPT_SOURCE_FILES
         src/twn_filewatch.c     src/twn_filewatch_c.h
         src/twn_filewatch.c     src/twn_filewatch_c.h
         src/twn_timer.c         src/twn_timer_c.h
+        src/twn_workers.c       src/twn_workers_c.h
 
         src/rendering/twn_draw.c src/rendering/twn_draw_c.h
         src/rendering/twn_quads.c
@@ -107,6 +105,8 @@ set(TWN_NONOPT_SOURCE_FILES
         src/rendering/twn_billboards.c
         src/rendering/twn_circles.c
         src/rendering/twn_skybox.c
+        src/rendering/twn_models.c
+        src/rendering/twn_lines.c
 )
 
 set(TWN_SOURCE_FILES
@@ -136,12 +136,10 @@ set_target_properties(${TWN_TARGET} PROPERTIES
                                     C_STANDARD_REQUIRED ON
                                     C_EXTENSIONS ON) # extensions are required by stb_ds.h
 
-target_compile_definitions(${TWN_TARGET} PRIVATE $<$<BOOL:${TWN_FEATURE_PUSH_AUDIO}>:TWN_FEATURE_PUSH_AUDIO>)
-
 # precompile commonly used not-so-small headers
 target_precompile_headers(${TWN_TARGET} PRIVATE
         $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:third-party/glad/include/glad/glad.h>
-        ${SDL2_INCLUDE_DIR}/SDL.h
+        $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:${SDL2_INCLUDE_DIR}/SDL.h>
         third-party/physfs/src/physfs.h)
 
 
@@ -153,14 +151,14 @@ function(give_options_without_warnings target)
                 -fno-signed-zeros
                 -fno-trapping-math
                 -freciprocal-math
+                # TODO: require packaging for web case
                 $<$<BOOL:${EMSCRIPTEN}>:-sUSE_SDL=2>)
 
         set(BUILD_FLAGS_RELEASE
                 -O3
                 -flto=$<IF:$<STREQUAL:${CMAKE_C_COMPILER_ID},Clang>,thin,auto>
-                -mavx -mavx2
+                $<$<STREQUAL:${CMAKE_SYSTEM_PROCESSOR},AMD64>:-sse2 -mavx -mavx2>
-                -fdata-sections
+                $<$<BOOL:${EMSCRIPTEN}>:-msimd128 -mrelaxed-simd>
-                -ffunction-sections
                 -funroll-loops
                 -fomit-frame-pointer
                 $<$<STREQUAL:${CMAKE_C_COMPILER_ID},Gnu>:-s>)
@@ -170,8 +168,20 @@ function(give_options_without_warnings target)
                 -g3
                 -gdwarf
                 -fno-omit-frame-pointer
-		$<$<BOOL:${TWN_SANITIZE}>:-fstack-protector-all -fsanitize=undefined -fsanitize=address>
+		$<$<BOOL:${TWN_SANITIZE}>:-fstack-protector-all -fsanitize=undefined -fsanitize=address>)
-                $<$<BOOL:${EMSCRIPTEN}>:-gsource-map>)
+
+        set(LINK_FLAGS
+                -Bsymbolic-functions
+
+                $<$<BOOL:${EMSCRIPTEN}>:-sLEGACY_GL_EMULATION -sGL_FFP_ONLY -sMIN_WEBGL_VERSION=2 -sMAX_WEBGL_VERSION=2
+                        -sENVIRONMENT=web -sDEFAULT_TO_CXX=0>
+                $<$<BOOL:${EMSCRIPTEN}>:--preload-file ${TWN_OUT_DIR}/data@data -sALLOW_MEMORY_GROWTH>
+                $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:-Wl,--as-needed>
+                $<$<BOOL:${LINUX}>:-Wl,--hash-style=gnu>)
+
+        set(LINK_FLAGS_RELEASE
+                $<$<STREQUAL:${CMAKE_C_COMPILER_ID},Clang>:-Wl,--strip-all>
+                ${BUILD_FLAGS_RELEASE})
 
         if (CMAKE_C_COMPILER_LINKER_ID MATCHES GNU OR CMAKE_C_COMPILER_LINKER_ID MATCHES GNUgold)
                 set(THINLTO_USAGE "-plugin-opt,")
@@ -193,11 +203,9 @@ function(give_options_without_warnings target)
 
         target_link_options(${target} PUBLIC
                                       ${BUILD_FLAGS}
-                                      # -Wl,--no-undefined # TODO: use later for implementing no-libc
+                                      ${LINK_FLAGS}
-                                      $<$<CONFIG:Release>:${BUILD_FLAGS_RELEASE}>
+                                      $<$<CONFIG:Release>:${LINK_FLAGS_RELEASE}>
-                                      $<$<CONFIG:Debug>:${BUILD_FLAGS_DEBUG}>
+                                      $<$<CONFIG:Debug>:${BUILD_FLAGS_DEBUG}>)
-                                      -Bsymbolic-functions
-                                      $<$<BOOL:${LINUX}>:-Wl,--hash-style=gnu>)
 
         get_target_property(target_type ${target} TYPE)
         if (target_type MATCHES SHARED_LIBRARY)
@@ -206,6 +214,9 @@ function(give_options_without_warnings target)
 
                 target_link_options(${target} PUBLIC
                                               $<$<CONFIG:Release>:${BUILD_SHARED_LIBRARY_FLAGS_RELEASE}>)
+        elseif(CMAKE_BUILD_TYPE MATCHES Release)
+                target_compile_options(${target} PUBLIC
+                                                 $<$<STREQUAL:${CMAKE_C_COMPILER_ID},Clang>:-mllvm=--enable-gvn-hoist>)
         endif()
 
         target_compile_definitions(${target} PRIVATE
@@ -236,6 +247,7 @@ function(give_options target)
                 -Werror=vla
                 -Wno-missing-field-initializers
                 -Wunused-result
+                -Wno-pre-c11-compat
                 $<$<STREQUAL:${CMAKE_C_COMPILER_ID},Gnu>:-Wcast-align=strict>)
 
         target_compile_options(${target} PRIVATE
@@ -254,6 +266,7 @@ function(include_deps target)
                 third-party/stb
                 third-party/dmon
                 third-party/tomlc99
+                third-party/fast_obj
                 $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:third-party/glad/include>)
 
         list(TRANSFORM THIRD_PARTY_INCLUDES PREPEND ${TWN_ROOT_DIR}/)
@@ -267,19 +280,40 @@ endfunction()
 function(link_deps target)
         target_link_libraries(${target} PUBLIC
                                         $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:SDL2::SDL2>
+                                        $<$<NOT:$<OR:$<BOOL:${TWN_FEATURE_DYNLIB_GAME}>,$<BOOL:${EMSCRIPTEN}>>>:SDL2::SDL2main>
                                         physfs-static
                                         xms)
 	target_include_directories(${target} PUBLIC ${SDL2_INCLUDE_DIRS})
 endfunction()
 
 
-function(use_townengine target sources output_directory)
+function(put_townengine output_directory)
+        cmake_path(GET TWN_OUT_DIR STEM LAST_ONLY target)
+
+        add_executable(${target} ${TWN_ROOT_DIR}/src/twn_main.c)
+        target_link_options(${target} PRIVATE $<$<BOOL:${LINUX}>:-Wl,-rpath,$ORIGIN/>)
+        set_target_properties(${TWN_TARGET} PROPERTIES
+                                            LIBRARY_OUTPUT_DIRECTORY ${output_directory})
+        set_target_properties(${target} PROPERTIES
+                                        OUTPUT_NAME ${target}
+                                        LIBRARY_OUTPUT_DIRECTORY ${output_directory}
+                                        RUNTIME_OUTPUT_DIRECTORY ${output_directory})
+        give_options(${target})
+        include_deps(${target})
+        link_deps(${target})
+        target_link_libraries(${target} PUBLIC ${TWN_TARGET})
+endfunction()
+
+
+function(use_townengine sources output_directory)
+        cmake_path(GET TWN_OUT_DIR STEM LAST_ONLY target)
+
         if(TWN_FEATURE_DYNLIB_GAME)
                 # game shared library, for reloading
                 add_library(${target}_game SHARED ${sources})
                 give_options(${target}_game)
                 include_deps(${target}_game)
-                target_link_libraries(${target}_game PUBLIC $<$<NOT:$<BOOL:${EMSCRIPTEN}>>:SDL2::SDL2> ${TWN_TARGET})
+                target_link_libraries(${target}_game PUBLIC ${TWN_TARGET})
                 set_target_properties(${target}_game PROPERTIES
                                                      OUTPUT_NAME game
                                                      LIBRARY_OUTPUT_DIRECTORY ${output_directory}
@@ -309,7 +343,7 @@ function(use_townengine target sources output_directory)
         endif()
 
         target_compile_options(${target} PRIVATE
-                                         $<$<BOOL:${EMSCRIPTEN}>:--shell-file ${TWN_ROOT_DIR}/shell_minimal.html>)
+                                         $<$<BOOL:${EMSCRIPTEN}>:--shell-file ${TWN_ROOT_DIR}/src/shell_minimal.html>)
 
         # system libraries
         find_library(MATH_LIBRARY m)
@@ -338,5 +372,18 @@ link_deps(twn_third_parties)
 give_options(${TWN_TARGET})
 include_deps(${TWN_TARGET})
 link_deps(${TWN_TARGET})
-target_link_libraries(${TWN_TARGET} PUBLIC twn_third_parties)
 target_include_directories(${TWN_TARGET} PRIVATE ${TWN_ROOT_DIR}/src)
+target_link_libraries(${TWN_TARGET} PUBLIC
+        twn_third_parties
+        ${CMAKE_CURRENT_BINARY_DIR}/font.o)
+
+# embed resources
+# TODO: think of a portable way to compress/decompress them
+add_custom_command(
+        OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/font.o
+        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+        COMMAND ${CMAKE_COMMAND} -E env CMAKE_CURRENT_BINARY_DIR=${CMAKE_CURRENT_BINARY_DIR} sh bin/prep-embed.sh
+        DEPENDS share/assets/Dernyns256.ttf)
+
+add_custom_target(asset-compilation ALL DEPENDS
+        ${CMAKE_CURRENT_BINARY_DIR}/font.o)

apps/demos/bunnymark/CMakeLists.txt

@@ -6,11 +6,11 @@ if(NOT CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
 
 set(SOURCE_FILES
         game.c
         state.h
 )
 
-use_townengine(${PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})
+use_townengine("${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/demos/bunnymark/data/packs/data.toml

@@ -1,3 +1,3 @@
 [[deps]]
-source = "../../../common-data"
+source = "../../../data"
 name = "common-data"

apps/demos/bunnymark/game.c

@@ -69,8 +69,8 @@ void game_tick(void)
             ctx.udata = calloc(1, sizeof(State));
     }
 
-    input_action("add_a_bit", CONTROL_LEFT_MOUSE);
+    input_action("add_a_bit", "LCLICK");
-    input_action("add_a_lot", CONTROL_RIGHT_MOUSE);
+    input_action("add_a_lot", "RCLICK");
 
     State *state = ctx.udata;
 

apps/demos/crawl/data/assets/LICENSES

@@ -0,0 +1 @@
+castledoors.png - https://opengameart.org/content/castle-door - CC-BY 3.0

apps/demos/crawl/data/levels/00.lvl

@@ -0,0 +1,37 @@
+@map
+-- Grid of symbols defined by @classes section.
+#####
+#.@.#
+#...#
+##.######
+#...X...#
+#./.#####
+#####
+
+
+@classes
+-- Defines classes under symbols, which could have properties attached.
+# stone_wall
+  wall_texture : /assets/brick.png
+  solid : 1
+. stone_floor
+  tile_texture : /assets/mossy_rock.png
+@ player_spawn
+  unique : 1
+  face : south
+  hold : torch
+  tile_texture : /assets/mossy_rock.png
+X door
+  open_on_signal : sg_torch0
+  tile_texture : /assets/mossy_rock.png
+  face : horizon
+  face_texture : /assets/castledoors.png
+/ lever
+  on_interact_emit : sg_torch0
+  tile_texture : /assets/mossy_rock.png
+  face : observer
+  face_texture : /assets/lever.png
+
+@meta
+-- Arbitrary sections could be defined with value pairs.
+description : Test Level! Just two square rooms and a tunnel opened by lever.

apps/demos/crawl/data/scripts/game.lua

@@ -0,0 +1,71 @@
+require("level")
+require("render")
+
+function lerp(a, b, x)
+    return a + ((b - a) * x)
+end
+
+function qlerp(a, b, x)
+    return lerp(a, b, x * x)
+end
+
+function game_tick()
+    if ctx.udata == nil then
+        ctx.udata = {
+            level = load_level("levels/00.lvl")
+        }
+        ctx.udata.player = {
+            position = ctx.udata.level.classes.player_spawn.position,
+            position_lerp = ctx.udata.level.classes.player_spawn.position,
+            direction = { x = 1, y = 0, z = 0 },
+            direction_lerp = { x = 1, y = 0, z = 0 },
+        }
+    end
+
+    input_action { control = "A", name = "turn_left" }
+    input_action { control = "D", name = "turn_right" }
+    input_action { control = "W", name = "walk_forward" }
+    input_action { control = "S", name = "walk_backward" }
+
+    if input_action_just_released { name = "turn_left" } then
+        ctx.udata.player.direction = { x = ctx.udata.player.direction.z,
+                                       y = ctx.udata.player.direction.y,
+                                       z =-ctx.udata.player.direction.x }
+    end
+
+    if input_action_just_released { name = "turn_right" } then
+        ctx.udata.player.direction = { x =-ctx.udata.player.direction.z,
+                                       y = ctx.udata.player.direction.y,
+                                       z = ctx.udata.player.direction.x }
+    end
+
+    local move = { x = 0, y = 0 }
+    if input_action_just_released { name = "walk_forward" } then
+        move = { x = move.x + ctx.udata.player.direction.x, y = move.y + ctx.udata.player.direction.z }
+    end
+    if input_action_just_released { name = "walk_backward" } then
+        move = { x = move.x - ctx.udata.player.direction.x, y = move.y - ctx.udata.player.direction.z }
+    end
+
+    if ctx.udata.level.grid[ctx.udata.player.position.y + move.y][ctx.udata.player.position.x + move.x].solid ~= nil then
+        move = { x = 0, y = 0 }
+    end
+
+    ctx.udata.player.position = { x = ctx.udata.player.position.x + move.x, y = ctx.udata.player.position.y + move.y }
+
+    ctx.udata.player.position_lerp.x = qlerp(ctx.udata.player.position_lerp.x, ctx.udata.player.position.x, ctx.frame_duration * 30)
+    ctx.udata.player.position_lerp.y = qlerp(ctx.udata.player.position_lerp.y, ctx.udata.player.position.y, ctx.frame_duration * 30)
+    ctx.udata.player.direction_lerp.x = qlerp(ctx.udata.player.direction_lerp.x, ctx.udata.player.direction.x, ctx.frame_duration * 40)
+    ctx.udata.player.direction_lerp.z = qlerp(ctx.udata.player.direction_lerp.z, ctx.udata.player.direction.z, ctx.frame_duration * 40)
+
+    draw_camera {
+        position = {
+            x = ctx.udata.player.position_lerp.x + 0.5 - ctx.udata.player.direction.x / 2,
+            y = 0.5,
+            z = ctx.udata.player.position_lerp.y + 0.5 - ctx.udata.player.direction.z / 2,
+        },
+        direction = ctx.udata.player.direction_lerp,
+    }
+
+    render_dungeon(ctx.udata.level)
+end

apps/demos/crawl/data/scripts/level.lua

@@ -0,0 +1,91 @@
+
+function load_level(file)
+    local f = file_read { file = file }
+
+    local result = {
+        -- templates to fill the grid with
+        classes = {
+            -- predefined empty tile
+            void = { },
+        },
+        -- symbol to class lookup table
+        glossary = {
+            [" "] = "void",
+        },
+        -- grid consists of expanded classes, of size dimensions
+        grid = {},
+        -- map consists of original rows of symbols that the grid is constructed from
+        map = {},
+        -- maximum extends of the map, unspecified tiles are filled with "void"
+        size = { x = 0, y = 0 },
+    }
+
+    -- iterate over lines
+    local section, subsection = "none", "none"
+    local from = 1
+    local start, limit = string.find(f, "\n", from)
+    while start do
+        local line = string.sub(f, from, start - 1)
+        -- skip over
+        if #line == 0 or line:find("^%-%-%s*") then
+            goto skip
+        -- start new section
+        elseif line:find("^@%g+") then
+            section = line:sub(2); subsection = "none"
+        -- decode map one line at a time
+        elseif section == "map" then
+            if result.size.x < #line then
+                result.size.x = #line
+            end
+            result.map[#result.map + 1] = line
+        -- templates to expand
+        elseif section == "classes" then
+            -- properties
+            if line:find("^  %g+") then
+                local _, _, property, value = line:find("^  (%g+)%s?:%s?(.*)")
+                result.classes[subsection][property] = value
+                goto skip
+            end
+            local symbol, classname = line:sub(1,1), line:sub(3)
+            result.classes[classname] = {
+                symbol = symbol,
+            }
+            result.glossary[symbol] = classname
+            subsection = classname
+        elseif section ~= "none" then
+            local _, _, property, value = line:find("^(%g+)%s?:%s?(.*)")
+            if result[section] == nil then
+                result[section] = {}
+            end
+            result[section][property] = value
+        end
+        ::skip::
+        from = limit + 1
+        start, limit = string.find(f, "\n", from)
+    end
+    -- post process, expand map to grid
+    for y = 1, #result.map do
+        result.grid[y] = {}
+        for x = 1, result.size.x do
+            -- past defined for line
+            local symbol
+            if x > #result.map[y] then
+                symbol = " "
+            else
+                symbol = result.map[y]:sub(x,x)
+            end
+            local class = result.classes[result.glossary[symbol]]
+            if class["unique"] ~= nil then
+                class.position = { x = x, y = y }
+            end
+            result.grid[y][x] = class
+            ::continue::
+        end
+    end
+
+    result.size.y = #result.map
+
+    print(result.meta.description)
+
+    return result
+end

apps/demos/crawl/data/scripts/render.lua

@@ -0,0 +1,88 @@
+-- if this is too wasteful, one could check nerby tiles to see whether faces could be visible
+-- more robust solution would be to travel the level from observer point of view
+function render_dungeon(dungeon)
+    for y = 1, dungeon.size.y do
+        for x = 1, dungeon.size.x do
+            if dungeon.grid[y][x].wall_texture ~= nil then
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = x,     y = 1, z = y },
+                    v2 = { x = x,     y = 0, z = y },
+                    v1 = { x = x + 1, y = 0, z = y },
+                    v0 = { x = x + 1, y = 1, z = y },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = x + 1, y = 1, z = y },
+                    v2 = { x = x + 1, y = 0, z = y },
+                    v1 = { x = x + 1, y = 0, z = y + 1 },
+                    v0 = { x = x + 1, y = 1, z = y + 1 },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = x + 1, y = 1, z = y + 1 },
+                    v2 = { x = x + 1, y = 0, z = y + 1 },
+                    v1 = { x = x,     y = 0, z = y + 1 },
+                    v0 = { x = x,     y = 1, z = y + 1 },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = x,     y = 1, z = y + 1 },
+                    v2 = { x = x,     y = 0, z = y + 1 },
+                    v1 = { x = x,     y = 0, z = y },
+                    v0 = { x = x,     y = 1, z = y },
+                    texture_region = { w = 128, h = 128 },
+                }
+
+            elseif dungeon.grid[y][x].tile_texture ~= nil then
+                draw_quad {
+                    texture = dungeon.grid[y][x].tile_texture,
+                    v0 = { x = x + 1, y = 0, z = y },
+                    v1 = { x = x,     y = 0, z = y },
+                    v2 = { x = x,     y = 0, z = y + 1 },
+                    v3 = { x = x + 1, y = 0, z = y + 1},
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].tile_texture,
+                    v3 = { x = x + 1, y = 1, z = y },
+                    v2 = { x = x,     y = 1, z = y },
+                    v1 = { x = x,     y = 1, z = y + 1 },
+                    v0 = { x = x + 1, y = 1, z = y + 1},
+                    texture_region = { w = 128, h = 128 },
+                }
+            end
+
+            if dungeon.grid[y][x].face_texture ~= nil then
+                if dungeon.grid[y][x].face == "horizon" then
+                    draw_quad {
+                        texture = dungeon.grid[y][x].face_texture,
+                        v3 = { x = x + 1, y = 1, z = y },
+                        v2 = { x = x + 1, y = 0, z = y },
+                        v1 = { x = x + 1, y = 0, z = y + 1 },
+                        v0 = { x = x + 1, y = 1, z = y + 1 },
+                        texture_region = { w = 64, h = 64 },
+                    }
+                    draw_quad {
+                        texture = dungeon.grid[y][x].face_texture,
+                        v3 = { x = x,     y = 1, z = y + 1 },
+                        v2 = { x = x,     y = 0, z = y + 1 },
+                        v1 = { x = x,     y = 0, z = y },
+                        v0 = { x = x,     y = 1, z = y },
+                        texture_region = { w = 64, h = 64 },
+                    }
+
+                elseif dungeon.grid[y][x].face == "observer" then
+                    draw_billboard {
+                        texture = dungeon.grid[y][x].face_texture,
+                        position = { x = x + 0.5, y = 0.5, z = y + 0.5 },
+                        size = { x = 0.5, y = 0.5 },
+                    }
+                end
+            end
+        end
+    end
+end

apps/demos/crawl/data/twn.toml

@@ -14,6 +14,7 @@ dev_id = "you"
 # Game runtime details
 [game]
 resolution = [ 640, 480 ]
+interpreter = "$TWNROOT/apps/twnlua"
 #debug = true
 
 # Engine tweaks. You probably don't need to change these

apps/demos/platformer/CMakeLists.txt

@@ -6,7 +6,7 @@ if(NOT CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
 
 set(SOURCE_FILES
         game.c
@@ -20,4 +20,4 @@ set(SOURCE_FILES
         scenes/ingame.c scenes/ingame.h
 )
 
-use_townengine(${PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})
+use_townengine("${SOURCE_FILES}" ${TWN_OUT_DIR})

apps/demos/platformer/data/packs/data.toml

@@ -1,3 +1,3 @@
 [[deps]]
-source = "../../../common-data" # where does it come from, might be an url
+source = "../../../data" # where does it come from, might be an url
 name = "common-data"         # should be globally unique

apps/demos/platformer/game.c

@@ -22,17 +22,13 @@ void game_tick(void) {
 
     State *state = ctx.udata;
 
-    input_action("debug_toggle", CONTROL_BACKSPACE);
+    input_action("debug_toggle", "BACKSPACE");
-    input_action("debug_dump_atlases", CONTROL_HOME);
+    input_action("debug_dump_atlases", "HOME");
 
     if (input_action_just_pressed("debug_toggle")) {
         ctx.debug = !ctx.debug;
     }
 
-    if (input_action_just_pressed("debug_dump_atlases")) {
-        textures_dump_atlases();
-    }
-
     state->scene->tick(state);
 
     /* there's a scene switch pending, we can do it now that the tick is done */

apps/demos/platformer/player.c

@@ -11,9 +11,9 @@
 
 
 static void update_timers(Player *player) {
-    player->jump_air_timer = timer_tick_frames(player->jump_air_timer);
+    player->jump_air_timer = player->jump_air_timer - 1 <= 0 ? 0 : player->jump_air_timer - 1;
-    player->jump_coyote_timer = timer_tick_frames(player->jump_coyote_timer);
+    player->jump_coyote_timer = player->jump_coyote_timer - 1 <= 0 ? 0 : player->jump_coyote_timer - 1;
-    player->jump_buffer_timer = timer_tick_frames(player->jump_buffer_timer);
+    player->jump_buffer_timer = player->jump_buffer_timer - 1 <= 0 ? 0 : player->jump_buffer_timer - 1;
 }
 
 

apps/demos/platformer/scenes/ingame.c

@@ -11,12 +11,17 @@
 static void ingame_tick(State *state) {
     SceneIngame *scn = (SceneIngame *)state->scene;
 
-    input_action("player_left", CONTROL_A);
+    input_action("player_left", "A");
-    input_action("player_right", CONTROL_D);
+    input_action("player_right", "D");
-    input_action("player_forward", CONTROL_W);
+    input_action("player_forward", "W");
-    input_action("player_backward", CONTROL_S);
+    input_action("player_backward", "S");
-    input_action("player_jump", CONTROL_SPACE);
+    input_action("player_jump", "SPACE");
-    input_action("player_run", CONTROL_LSHIFT);
+    input_action("player_run", "LSHIFT");
+
+    draw_camera_2d((Vec2){ scn->player->rect.x + scn->player->rect.w / 2 - ctx.resolution.x / 2,
+                           scn->player->rect.y + scn->player->rect.h / 2 - ctx.resolution.y / 2 },
+        0, 1
+    );
 
     world_drawdef(scn->world);
     player_calc(scn->player);

apps/demos/platformer/scenes/title.c

@@ -13,7 +13,7 @@ static void title_tick(State *state) {
     SceneTitle *scn = (SceneTitle *)state->scene;
     (void)scn;
 
-    input_action("ui_accept", CONTROL_RETURN);
+    input_action("ui_accept", "ENTER");
 
     if (input_action_just_pressed("ui_accept")) {
         switch_to(state, ingame_scene);
@@ -27,7 +27,6 @@ static void title_tick(State *state) {
     size_t text_str_len = snprintf(NULL, 0, "%llu", (unsigned long long)state->ctx->frame_number) + 1;
     char *text_str = malloc(text_str_len);
     snprintf(text_str, text_str_len, "%llu", (unsigned long long)state->ctx->frame_number);
-    free(text_str);
 
     const char *font = "fonts/kenney-pixel.ttf";
     float text_h = 32;

apps/demos/scenery/CMakeLists.txt

@@ -6,15 +6,14 @@ if(NOT CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
 
 set(SOURCE_FILES
         game.c
         state.h
 
         scenes/scene.c scenes/scene.h
-        scenes/title.c scenes/title.h
         scenes/ingame.c scenes/ingame.h
 )
 
-use_townengine(${PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})
+use_townengine("${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/demos/scenery/data/packs/data.toml

@@ -1,3 +1,3 @@
 [[deps]]
-source = "../../../common-data" # where does it come from, might be an url
+source = "../../../data" # where does it come from, might be an url
-name = "common-data"         # should be globally unique
+name = "common-data"     # should be globally unique

apps/demos/scenery/game.c

@@ -1,6 +1,5 @@
 #include "state.h"
 #include "scenes/scene.h"
-#include "scenes/title.h"
 #include "scenes/ingame.h"
 
 #include "twn_game_api.h"
@@ -18,23 +17,19 @@ void game_tick(void) {
 
             State *state = ctx.udata;
             state->ctx = &ctx;
-            state->scene = title_scene(state);
+            state->scene = ingame_scene(state);
         }
     }
 
     State *state = ctx.udata;
 
-    input_action("debug_toggle", CONTROL_BACKSPACE);
+    input_action("debug_toggle", "BACKSPACE");
-    input_action("debug_dump_atlases", CONTROL_HOME);
+    input_action("debug_dump_atlases", "HOME");
 
     if (input_action_just_pressed("debug_toggle")) {
         ctx.debug = !ctx.debug;
     }
 
-    if (input_action_just_pressed("debug_dump_atlases")) {
-        textures_dump_atlases();
-    }
-
     state->scene->tick(state);
 
     /* there's a scene switch pending, we can do it now that the tick is done */

apps/demos/scenery/scenes/ingame.c

@@ -1,5 +1,4 @@
 #include "ingame.h"
-#include "title.h"
 #include "scene.h"
 
 #include "twn_game_api.h"
@@ -13,21 +12,298 @@
 
 
 #define TERRAIN_FREQUENCY 0.15f
-#define TERRAIN_DISTANCE 64
+#define TERRAIN_RADIUS 128
+#define GRASS_RADIUS 16
+#define TERRAIN_DISTANCE (TERRAIN_RADIUS * 2)
 #define HALF_TERRAIN_DISTANCE ((float)TERRAIN_DISTANCE / 2)
 #define PLAYER_HEIGHT 0.6f
+#define TREE_DENSITY 0.03f
 
+#define G_CONST 10.0f
+
+/* TODO: pregenerate grid of levels of detail */
 static float heightmap[TERRAIN_DISTANCE][TERRAIN_DISTANCE];
 
 
+/* vehicle sim ! */
+/* https://www.youtube.com/watch?v=pwbwFdWBkU0 */
+/* representation is a "jelly" box with spring configuration trying to make it coherent */
+
+/* == springs == */
+/* damped spring: F = -kx - cv */
+/* x = length(p1-p0) - at_rest_length */
+/* v = dot(v1 - v0, unit(p1-p0)) */
+/* F = (-kx - cv) * unit(p1-p0) */
+/* v += (F/m)*t */
+/* one points gains positive F, other negative F, to come together */
+
+/* == ground interaction == */
+/* if point is under terrain, then apply this: */
+/* x = y difference on point and ground */
+/* -x(n) = x * normal */
+/* -v(n) = dot(v, normal) */
+/* -F = (-kx(n)-cv(n)) * normal */
+
+/* == friction == */
+/* v(o)/F(o) are perpendicular to slope (x - x(n)) */
+/* if v(o) == 0, then */
+/*     -- at rest, static friction overcomes */
+/*     if F(o) <= f(s)*x(n), F(o) = 0 */
+/*     else, F(o) -= f(k) * x(n) */
+/* else if length(v(o) + (F(o)/m)*t) <= (f(k)*x(n)*t), v(o) = 0 */
+/*     else, F = -unit(v(o)*f(k)*x(n)) */
+
+#define VEHICLE_MASS 200.0f
+#define VEHICLE_LENGTH 3.0f
+#define VEHICLE_WIDTH 1.7f
+#define VEHICLE_HEIGHT 1.3f
+/* spring constant */
+#define VEHICLE_SPRING_K 22000.0f
+#define VEHICLE_SPRING_K_SHOCK 18000.0f
+#define VEHICLE_SPRING_GK 70000.0f
+/* damping constant */
+#define VEHICLE_SPRING_C 800.0f
+#define VEHICLE_SPRING_C_SHOCK 500.0f
+#define VEHICLE_SPRING_GC 100.0f
+#define VEHICLE_FRICTION_S 1000.0f
+#define VEHICLE_FRICTION_K 110.0f
+#define VEHICLE_FRICTION_V 4000.0f
+
+/* TODO: shock springs, that are more loose, which are used to simulate the wheels */
+/* initial, ideal corner positions */
+static const Vec3 vbpi[8] = {
+    [0] = { 0, 0, 0 },
+    [1] = { VEHICLE_LENGTH, 0, 0 },
+    [2] = { VEHICLE_LENGTH, 0, VEHICLE_WIDTH },
+    [3] = { 0, 0, VEHICLE_WIDTH },
+    [4] = { 0, VEHICLE_HEIGHT, 0 },
+    [5] = { VEHICLE_LENGTH, VEHICLE_HEIGHT, 0 },
+    [6] = { VEHICLE_LENGTH, VEHICLE_HEIGHT, VEHICLE_WIDTH },
+    [7] = { 0, VEHICLE_HEIGHT, VEHICLE_WIDTH },
+};
+/* corner positions in simulation */
+static Vec3 vbp[8] = { vbpi[0], vbpi[1], vbpi[2], vbpi[3],
+                       vbpi[4], vbpi[5], vbpi[6], vbpi[7], };
+/* corner velocities */
+static Vec3 vbv[8];
+/* springs */
+static uint8_t vbs[28][2] = {
+    {0, 1}, {4, 5}, {0, 4},
+    {1, 2}, {5, 6}, {1, 5},
+    {2, 3}, {6, 7}, {2, 6},
+    {3, 0}, {7, 4}, {3, 7},
+
+    {0, 2}, {0, 5}, {0, 7},
+    {1, 3}, {1, 6}, {1, 4},
+    {4, 6}, {2, 7}, {2, 5},
+    {5, 7}, {3, 4}, {3, 6},
+
+    {0, 6}, {1, 7}, {2, 4}, {3, 5},
+};
+/* ackermann steering geometry */
+static float vehicle_turning_extend;
+static float vehicle_turning_speed = 0.12f;
+static float vehicle_turning_extend_limit = VEHICLE_WIDTH * 1.75f;
+
+static float height_at(SceneIngame *scn, Vec2 position);
+static Vec3 normal_at(SceneIngame *scn, Vec2 position);
+
+
+static inline float clampf(float f, float min, float max) {
+    const float t = f < min ? min : f;
+    return t > max ? max : t;
+}
+
+
+static void draw_vehicle(SceneIngame *scn) {
+    for (size_t i = 0; i < 12; ++i)
+        draw_line_3d(vbp[vbs[i][0]], vbp[vbs[i][1]], 1, (Color){255, 255, 255, 255});
+    for (size_t i = 12; i < 24; ++i)
+        draw_line_3d(vbp[vbs[i][0]], vbp[vbs[i][1]], 1, (Color){200, 200, 200, 255});
+    for (size_t i = 24; i < 28; ++i)
+        draw_line_3d(vbp[vbs[i][0]], vbp[vbs[i][1]], 1, (Color){255, 125, 125, 255});
+}
+
+
+static void process_vehicle(SceneIngame *scn) {
+    /* apply gravity */
+    Vec3 Facc[8] = {0};
+
+    /* steering */
+    bool steered = false;
+    if (input_action_pressed("player_left")) {
+        vehicle_turning_extend -= vehicle_turning_speed;
+        steered = true;
+    }
+
+    if (input_action_pressed("player_right")) {
+        vehicle_turning_extend += vehicle_turning_speed;
+        steered = true;
+    }
+
+    if (!steered)
+        vehicle_turning_extend -= copysignf(vehicle_turning_speed * 0.9f, vehicle_turning_extend);
+
+    vehicle_turning_extend = clampf(vehicle_turning_extend, -vehicle_turning_extend_limit, vehicle_turning_extend_limit);
+    if (fabsf(vehicle_turning_extend) <= 0.11f)
+        vehicle_turning_extend = 0;
+
+    Vec3 const Fg = { .y = -VEHICLE_MASS * G_CONST };
+    for (size_t i = 0; i < 8; ++i)
+        Facc[i] = vec3_add(Facc[i], Fg);
+
+    /* apply springs */
+    for (size_t i = 0; i < 28; ++i) {
+        Vec3 const p0 = vbp[vbs[i][0]];
+        Vec3 const p1 = vbp[vbs[i][1]];
+        Vec3 const v0 = vbv[vbs[i][0]];
+        Vec3 const v1 = vbv[vbs[i][1]];
+        Vec3 const pd = vec3_sub(p1, p0);
+        Vec3 const pn = vec3_norm(pd);
+        /* TODO: length at rest could be precalculated */
+        float const lar = vec3_length(vec3_sub(vbpi[vbs[i][1]], vbpi[vbs[i][0]]));
+        float const x = vec3_length(pd) - lar;
+        float const v = vec3_dot(vec3_sub(v1, v0), pn);
+        float const spring_k = i == 2 | i == 5 || i == 8 || i == 11 ? VEHICLE_SPRING_K_SHOCK : VEHICLE_SPRING_K;
+        float const spring_c = i == 2 | i == 5 || i == 8 || i == 11 ? VEHICLE_SPRING_C_SHOCK : VEHICLE_SPRING_C;
+        Vec3 const Fs = vec3_scale(pn, -spring_k * x - spring_c * v);
+        Facc[vbs[i][0]] = vec3_sub(Facc[vbs[i][0]], Fs);
+        Facc[vbs[i][1]] = vec3_add(Facc[vbs[i][1]], Fs);
+    }
+
+    /* spring and friction against the ground */
+    for (size_t i = 0; i < 8; ++i) {
+        Vec3 const p = vbp[i];
+        Vec3 const v = vbv[i];
+        float const h = height_at(scn, (Vec2){ p.x, p.z });
+        Vec3 const fwd = vec3_norm(vec3_sub(vbp[1], vbp[0]));
+        if (h >= p.y) {
+            /* back wheel processing: acceleration */
+            if (i == 0 || i == 3) {
+                float scale = 0;
+                if (scn->camera_mode == 2 && input_action_pressed("player_forward"))
+                    scale += 1;
+                if (scn->camera_mode == 2 && input_action_pressed("player_backward"))
+                    scale -= 1;
+                Facc[i] = vec3_add(Facc[i], vec3_scale(fwd, 6500 * scale));
+            }
+
+            /* normal force, for displacement */
+            Vec3 const n = normal_at(scn, (Vec2){ p.x, p.z });
+            float const xn = (h - p.y) * n.y;
+            float const vn = vec3_dot(v, n);
+            Vec3 const Fn = vec3_scale(n, -VEHICLE_SPRING_GK * xn - VEHICLE_SPRING_GC * vn);
+            Facc[i] = vec3_sub(Facc[i], Fn);
+
+            /* friction force, perpendicular to normal force */
+            /* TODO: is it right? aren't vn+vol should be = |v| */
+            Vec3 const von = vec3_norm(vec3_cross(n, vec3_cross(v, n)));
+            Vec3 const vo = vec3_scale(vec3_scale(von, vec3_length(v) - vn), -1);
+            float const vol = vec3_length(vo);
+            Vec3 const Fon = vec3_norm(vec3_cross(n, vec3_cross(Facc[i], n)));
+            Vec3 Fo = vec3_scale(vec3_scale(Fon, vec3_length(Facc[i]) - vec3_dot(Facc[i], n)), -1);
+            /* portion of total force along the surface */
+            float const Fol = vec3_length(Fo);
+            float const fkxn = VEHICLE_FRICTION_K * xn;
+            /* at rest, might want to start moving */
+            if (fabsf(0.0f - vol) <= 0.0001f) {
+                /* cannot overcome static friction, force along the surface is zeroed */
+                if (Fol <= VEHICLE_FRICTION_S * xn) { Fo = vec3_scale(Fo, -1);}
+                /* resist the force by friction, while starting to move */
+                else { Fo = vec3_sub(Fo, vec3_scale(von, fkxn));}
+            /* not at rest, stop accelerating along the surface */
+            } else if (vol + (Fol / VEHICLE_MASS) * ctx.frame_duration <= fkxn * ctx.frame_duration * 2) {
+                /* ugh ... */
+                vbv[i] = vec3_add(v, vo);
+            /* just apply friction */
+            } else {
+                Fo = vec3_scale(von, -fkxn * 400);
+            }
+            Facc[i] = vec3_add(Facc[i], Fo);
+
+            /* rear wheel friction */
+            if (i == 0 || i == 3) {
+                Vec3 const pn = vec3_cross(fwd, n);
+                Vec3 const Fp = vec3_scale(pn, vec3_dot(v, pn) * -VEHICLE_FRICTION_V);
+                Facc[i] = vec3_add(Facc[i], Fp);
+            }
+
+            /* front wheel processing */
+            if (i == 1 || i == 2) {
+                /* steering influences "center of turning", which is a point */
+                /* laying on line defined by rear axle */
+                /* front arms are rotated to be perpendicular to center of turning, */
+                /* which then are used to dissipate forces, thus providing control */
+                Vec3 const rear_bar = vec3_sub(vbp[0], vbp[3]);
+                Vec3 const rear_center = vec3_scale(vec3_add(vbp[0], vbp[3]), 0.5);
+                Vec3 a, b, r;
+                if (i == 1) {
+                    a = vec3_sub(vbp[3], vbp[2]);
+                    b = vec3_sub(rear_center, vbp[2]);
+                    r = vbp[2];
+                } else {
+                    a = vec3_sub(vbp[0], vbp[1]);
+                    b = vec3_sub(rear_center, vbp[1]);
+                    r = vbp[1];
+                }
+
+               float const arm_angle = vec3_angle(a, b);
+                Vec3 const turn_center = vec3_add(rear_center, vec3_scale(vec3_norm(rear_bar), vehicle_turning_extend));
+                Vec3 const arm = vec3_sub(r, turn_center);
+                Vec3 const n = vec3_norm(vec3_cross(a, b));
+                Vec3 const wheel = vec3_norm(vec3_rotate(arm, -arm_angle, n));
+                Vec3 const p = vec3_norm(vec3_cross(wheel, n));
+                draw_line_3d(r, vec3_add(r, p), 1, (Color){0,255,255,255});
+
+                Vec3 const Fp = vec3_scale(p, vec3_dot(v, p) * -VEHICLE_FRICTION_V);
+                Facc[i] = vec3_add(Facc[i], Fp);
+            }
+        }
+
+        Vec3 vd = vec3_scale(vec3_scale(Facc[i], (1.0f / VEHICLE_MASS)), ctx.frame_duration);
+        vbv[i] = vec3_add(vbv[i], vd);
+        vbp[i] = vec3_add(vbp[i], vec3_scale(vbv[i], ctx.frame_duration));
+    }
+}
+
+
+static void process_vehicle_mode(State *state) {
+    SceneIngame *scn = (SceneIngame *)state->scene;
+
+    Vec3 const top_center = vec3_sub(vbp[4], vec3_scale(vec3_sub(vbp[4], vbp[6]), 1.0f / 2.0f));
+    // Vec3 const front_center = vec3_add(vbp[4], vec3_scale(vec3_sub(vbp[4], vbp[7]), 1.0f / 2.0f));
+    // Vec3 const facing_direction = vec3_sub(top_center, front_center);
+
+    float yawc, yaws, pitchc, pitchs;
+    sincosf(scn->yaw + (float)M_PI_2, &yaws, &yawc);
+    sincosf(scn->pitch, &pitchs, &pitchc);
+
+    Vec3 const looking_direction = vec3_norm(((Vec3){
+        yawc * pitchc,
+        pitchs,
+        yaws * pitchc,
+    }));
+
+    Vec3 const orbit = vec3_sub(top_center, vec3_scale(looking_direction, 7.5));
+
+    draw_camera(orbit, looking_direction, (Vec3){0,1,0}, (float)M_PI_2 * 0.8f, 1, TERRAIN_RADIUS * sqrtf(3));
+
+    scn->looking_direction = looking_direction;
+
+    scn->pos = top_center;
+}
+
+
 static void process_fly_mode(State *state) {
     SceneIngame *scn = (SceneIngame *)state->scene;
 
     DrawCameraFromPrincipalAxesResult dir_and_up =
-        draw_camera_from_principal_axes(scn->pos, scn->roll, scn->pitch, scn->yaw, (float)M_PI_2 * 0.8f, 1);
+        draw_camera_from_principal_axes(scn->pos, scn->roll, scn->pitch, scn->yaw, (float)M_PI_2 * 0.8f, 1, TERRAIN_RADIUS * sqrtf(3));
+
+    scn->looking_direction = dir_and_up.direction;
 
     const Vec3 right = m_vec_norm(m_vec_cross(dir_and_up.direction, dir_and_up.up));
-    const float speed = 0.04f; /* TODO: put this in a better place */
+    const float speed = 0.1f; /* TODO: put this in a better place */
     if (input_action_pressed("player_left"))
         scn->pos = vec3_sub(scn->pos, m_vec_scale(right, speed));
 
@@ -47,33 +323,39 @@ static void process_fly_mode(State *state) {
         scn->pos.y -= speed;
 }
 
+/* TODO: could be baked in map format */
+static Vec3 normal_at(SceneIngame *scn, Vec2 position) {
+    int const x = (int)(floorf(position.x - scn->world_center.x));
+    int const y = (int)(floorf(position.y - scn->world_center.y));
 
+    float const height0 = heightmap[x][y];
+    float const height1 = heightmap[x + 1][y];
+    float const height2 = heightmap[x][y + 1];
+
+    Vec3 const a = { .x = 1, .y = height0 - height1, .z = 0 };
+    Vec3 const b = { .x = 0, .y = height0 - height2, .z = -1 };
+
+    return vec3_norm(vec3_cross(a, b));
+}
+
+/* TODO: don't operate on triangles, instead interpolate on quads */
 static float height_at(SceneIngame *scn, Vec2 position) {
-    float height0, height1, height2, weight0, weight1, weight2;
+    int const x = (int)(floorf(position.x - scn->world_center.x));
+    int const y = (int)(floorf(position.y - scn->world_center.y));
 
-    int const x = (int)(HALF_TERRAIN_DISTANCE + (position.x - scn->pos.x));
+    float const height0 = heightmap[x][y];
-    int const y = (int)(HALF_TERRAIN_DISTANCE + (position.y - scn->pos.z));
+    float const height1 = heightmap[x + 1][y];
-
+    float const height2 = heightmap[x][y + 1];
-    height0 = heightmap[x][y];
+    float const height3 = heightmap[x + 1][y + 1];
-    height1 = heightmap[x + 1][y + 1];
 
     Vec2 incell = { position.x - floorf(position.x), position.y - floorf(position.y) };
 
-    /* who needs barycentric coordinates, am i right? */
+    float const weight0 = (1 - incell.x) * (1 - incell.y);
-    weight0 = 1 / sqrtf(powf(incell.x, 2) + powf(incell.y, 2));
+    float const weight1 = ( incell.x) * (1 - incell.y);
-    weight1 = 1 / sqrtf(powf(1 - incell.x, 2) + powf(1 - incell.y, 2));
+    float const weight2 = (1 - incell.x) * ( incell.y);
+    float const weight3 = ( incell.x) * ( incell.y);
 
-    /* find which triangle we're directly under */
+    return (height0 * weight0 + height1 * weight1 + height2 * weight2 + height3 * weight3) / (weight0 + weight1 + weight2 + weight3);
-    /* for this manhattan distance is sufficient */
-    if (incell.x + (1 - incell.y) < (1 - incell.x) + incell.y) {
-        height2 = heightmap[x][y + 1];
-        weight2 = 1 / sqrtf(powf(incell.x, 2) + powf(1 - incell.y, 2));
-    } else {
-        height2 = heightmap[x + 1][y];
-        weight2 = 1 / sqrtf(powf(1 - incell.x, 2) + powf(incell.y, 2));
-    }
-
-    return (height0 * weight0 + height1 * weight1 + height2 * weight2) / (weight0 + weight1 + weight2);
 }
 
 
@@ -81,13 +363,15 @@ static void process_ground_mode(State *state) {
     SceneIngame *scn = (SceneIngame *)state->scene;
 
     DrawCameraFromPrincipalAxesResult dir_and_up =
-        draw_camera_from_principal_axes(scn->pos, scn->roll, scn->pitch, scn->yaw, (float)M_PI_2 * 0.8f, 1);
+        draw_camera_from_principal_axes(scn->pos, scn->roll, scn->pitch, scn->yaw, (float)M_PI_2 * 0.8f, 1, TERRAIN_RADIUS * sqrtf(3));
+
+    scn->looking_direction = dir_and_up.direction;
 
     dir_and_up.direction.y = 0;
     dir_and_up.direction = vec3_norm(dir_and_up.direction);
 
     const Vec3 right = m_vec_norm(m_vec_cross(dir_and_up.direction, dir_and_up.up));
-    const float speed = 0.18f; /* TODO: put this in a better place */
+    const float speed = 0.20f; /* TODO: put this in a better place */
 
     Vec3 target = scn->pos;
 
@@ -96,7 +380,7 @@ static void process_ground_mode(State *state) {
         float const height = height_at(scn, (Vec2){scn->pos.x, scn->pos.z});
 
         if (target.y > height + PLAYER_HEIGHT)
-            target.y = target.y - 0.4f;
+            target.y = target.y - 0.6f;
 
         if (target.y < height + PLAYER_HEIGHT)
             target.y = height + PLAYER_HEIGHT;
@@ -135,50 +419,100 @@ static void generate_terrain(SceneIngame *scn) {
             float y = floorf(scn->pos.z - HALF_TERRAIN_DISTANCE + (float)ly);
 
             float height = stb_perlin_noise3((float)x * TERRAIN_FREQUENCY, (float)y * TERRAIN_FREQUENCY, 0, 0, 0, 0) * 3 - 1;
-            height += stb_perlin_noise3((float)x * TERRAIN_FREQUENCY / 10, (float)y * TERRAIN_FREQUENCY / 10, 0, 0, 0, 0) * 10 - 1;
+            height += stb_perlin_noise3((float)x * TERRAIN_FREQUENCY / 10, (float)y * TERRAIN_FREQUENCY / 10, 0, 0, 0, 0) * 20 - 1;
 
             heightmap[lx][ly] = height;
         }
     }
+
+    scn->world_center = (Vec2){ floorf(scn->pos.x - HALF_TERRAIN_DISTANCE), floorf(scn->pos.z - HALF_TERRAIN_DISTANCE) };
+}
+
+
+static int32_t ceil_sqrt(int32_t const n) {
+    int32_t res = 1;
+    while(res * res < n)
+        res++;
+    return res;
+}
+
+
+static uint32_t adler32(const void *buf, size_t buflength) {
+     const uint8_t *buffer = (const uint8_t*)buf;
+
+     uint32_t s1 = 1;
+     uint32_t s2 = 0;
+
+     for (size_t n = 0; n < buflength; n++) {
+        s1 = (s1 + buffer[n]) % 65521;
+        s2 = (s2 + s1) % 65521;
+     }
+     return (s2 << 16) | s1;
 }
 
 
 static void draw_terrain(SceneIngame *scn) {
-    for (int ly = TERRAIN_DISTANCE - 1; ly > 0; ly--) {
+    /* used to cull invisible tiles over field of view (to horizon) */
-        for (int lx = 0; lx < TERRAIN_DISTANCE - 1; lx++) {
+    Vec2 const d = vec2_norm((Vec2){ .x = scn->looking_direction.x, .y = scn->looking_direction.z });
-            int32_t x = (int32_t)(floorf(scn->pos.x - HALF_TERRAIN_DISTANCE + (float)lx));
+    float const c = cosf((float)M_PI_2 * 0.8f * 0.8f);
-            int32_t y = (int32_t)(floorf(scn->pos.z - HALF_TERRAIN_DISTANCE + (float)ly));
+
+    /* draw terrain in circle */
+    int32_t const rsi = (int32_t)TERRAIN_RADIUS * (int32_t)TERRAIN_RADIUS;
+    for (int32_t iy = -(int32_t)TERRAIN_RADIUS; iy <= (int32_t)TERRAIN_RADIUS - 1; ++iy) {
+        int32_t const dx = ceil_sqrt(rsi - (iy + (iy <= 0)) * (iy + (iy <= 0)));
+        for (int32_t ix = -dx; ix < dx - 1; ++ix) {
+            int32_t lx = ix + TERRAIN_RADIUS;
+            int32_t ly = iy + TERRAIN_RADIUS;
+
+            float x = (float)(floorf(scn->pos.x - HALF_TERRAIN_DISTANCE + (float)lx));
+            float y = (float)(floorf(scn->pos.z - HALF_TERRAIN_DISTANCE + (float)ly));
+
+            /* cull tiles outside of vision */
+            if (vec2_dot(vec2_norm((Vec2){x - scn->pos.x + d.x * 2, y - scn->pos.z + d.y * 2}), d) < c)
+                continue;
 
             float d0 = heightmap[lx][ly];
             float d1 = heightmap[lx + 1][ly];
             float d2 = heightmap[lx + 1][ly - 1];
             float d3 = heightmap[lx][ly - 1];
 
-            draw_triangle("/assets/grass.png",
+            draw_quad("/assets/grass2.png",
                             (Vec3){ (float)x,     d0, (float)y },
-                            (Vec3){ (float)x + 1, d1, (float)y },
-                            (Vec3){ (float)x,     d3, (float)y - 1 },
-                            (Vec2){ 128, 128 },
-                            (Vec2){ 128, 0 },
-                            (Vec2){ 0, 128 },
-                            (Color){255, 255, 255, 255},
-                            (Color){255, 255, 255, 255},
-                            (Color){255, 255, 255, 255});
-
-            draw_triangle("/assets/grass.png",
                             (Vec3){ (float)x + 1, d1, (float)y },
                             (Vec3){ (float)x + 1, d2, (float)y - 1 },
                             (Vec3){ (float)x,     d3, (float)y - 1 },
-                            (Vec2){ 128, 0 },
+                            (Rect){ .w = 128, .h = 128 },
-                            (Vec2){ 0, 0 },
-                            (Vec2){ 0, 128 },
-                            (Color){255, 255, 255, 255},
-                            (Color){255, 255, 255, 255},
                             (Color){255, 255, 255, 255});
 
-            draw_billboard("/assets/grasses/10.png",
+            if (((float)(adler32(&((Vec2){x, y}), sizeof (Vec2)) % 100) / 100) <= TREE_DENSITY)
-                          (Vec3){ (float)x, d0 + 0.15f, (float)y },
+                draw_billboard("/assets/trreez.png",
-                          (Vec2){0.3f, 0.3f},
+                              (Vec3){ (float)x, d0 + 1.95f, (float)y },
+                              (Vec2){2.f, 2.f},
+                              (Rect){0},
+                              (Color){255, 255, 255, 255}, true);
+        }
+    }
+
+    int32_t const rsi_g = (int32_t)GRASS_RADIUS * (int32_t)GRASS_RADIUS;
+    for (int32_t iy = -(int32_t)GRASS_RADIUS; iy <= (int32_t)GRASS_RADIUS - 1; ++iy) {
+        int32_t const dx = ceil_sqrt(rsi_g - (iy + (iy <= 0)) * (iy + (iy <= 0)));
+        for (int32_t ix = -dx; ix < dx; ++ix) {
+            int32_t lx = ix + TERRAIN_RADIUS;
+            int32_t ly = iy + TERRAIN_RADIUS;
+
+            float x = (float)(floorf(scn->pos.x - HALF_TERRAIN_DISTANCE + (float)lx));
+            float y = (float)(floorf(scn->pos.z - HALF_TERRAIN_DISTANCE + (float)ly));
+
+            float d = heightmap[lx][ly];
+
+            draw_billboard("/assets/grasses/25.png",
+                          (Vec3){
+                              (float)x + (float)((adler32(&((Vec2){x, y}), sizeof (Vec2))) % 32) / 64.0f,
+                              d + 0.2f,
+                              (float)y + (float)((adler32(&((Vec2){y, x}), sizeof (Vec2))) % 32) / 64.0f
+                          },
+                          (Vec2){0.4f, 0.4f},
+                          (Rect){0},
                           (Color){255, 255, 255, 255}, true);
         }
     }
@@ -188,29 +522,31 @@ static void draw_terrain(SceneIngame *scn) {
 static void ingame_tick(State *state) {
     SceneIngame *scn = (SceneIngame *)state->scene;
 
-    input_action("player_left", CONTROL_A);
+    input_action("player_left", "A");
-    input_action("player_right", CONTROL_D);
+    input_action("player_right", "D");
-    input_action("player_forward", CONTROL_W);
+    input_action("player_forward", "W");
-    input_action("player_backward", CONTROL_S);
+    input_action("player_backward", "S");
-    input_action("player_jump", CONTROL_SPACE);
+    input_action("player_jump", "SPACE");
-    input_action("player_run", CONTROL_LSHIFT);
+    input_action("player_run", "LSHIFT");
-    input_action("mouse_capture_toggle", CONTROL_ESCAPE);
+    input_action("mouse_capture_toggle", "ESCAPE");
-    input_action("toggle_camera_mode", CONTROL_C);
+    input_action("toggle_camera_mode", "C");
 
     if (scn->mouse_captured) {
-        const float sensitivity = 0.4f * (float)DEG2RAD; /* TODO: put this in a better place */
+        const float sensitivity = 0.4f * (float)(M_PI / 180); /* TODO: put this in a better place */
         scn->yaw += (float)ctx.mouse_movement.x * sensitivity;
         scn->pitch -= (float)ctx.mouse_movement.y * sensitivity;
         scn->pitch = clampf(scn->pitch, (float)-M_PI * 0.49f, (float)M_PI * 0.49f);
     }
 
     if (input_action_just_pressed("toggle_camera_mode"))
-        scn->flying_camera = !scn->flying_camera;
+        scn->camera_mode = scn->camera_mode == 2 ? 0 : scn->camera_mode + 1;
 
-    if (scn->flying_camera) {
+    if (scn->camera_mode == 1) {
         process_fly_mode(state);
-    } else {
+    } else if (scn->camera_mode == 0) {
         process_ground_mode(state);
+    } else if (scn->camera_mode) {
+        process_vehicle_mode(state);
     }
 
     /* toggle mouse capture with end key */
@@ -220,12 +556,15 @@ static void ingame_tick(State *state) {
     ctx.mouse_capture = scn->mouse_captured;
 
     generate_terrain(scn);
+    process_vehicle(scn);
+
     draw_terrain(scn);
+    draw_vehicle(scn);
 
     draw_skybox("/assets/miramar/miramar_*.tga");
 
     ctx.fog_color = (Color){ 140, 147, 160, 255 };
-    ctx.fog_density = 0.03f;
+    ctx.fog_density = 0.015f;
 }
 
 
@@ -243,7 +582,7 @@ Scene *ingame_scene(State *state) {
 
     new_scene->mouse_captured = true;
 
-    m_audio(m_set(path, "music/mod65.xm"),
+    m_audio(m_set(path, "music/woah.ogg"),
             m_opt(channel, "soundtrack"),
             m_opt(repeat, true));
 

apps/demos/scenery/scenes/ingame.h

@@ -12,13 +12,16 @@
 typedef struct SceneIngame {
     Scene base;
 
+    Vec3 looking_direction;
+    Vec2 world_center;
+
     Vec3 pos;
     float yaw;
     float pitch;
     float roll;
 
     bool mouse_captured;
-    bool flying_camera;
+    int camera_mode;
 } SceneIngame;
 
 

apps/demos/scenery/scenes/title.c

@@ -1,61 +0,0 @@
-#include "title.h"
-#include "ingame.h"
-
-#include "twn_game_api.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-
-
-static void title_tick(State *state) {
-    SceneTitle *scn = (SceneTitle *)state->scene;
-    (void)scn;
-
-    input_action("ui_accept", CONTROL_RETURN);
-
-    if (input_action_just_pressed("ui_accept")) {
-        switch_to(state, ingame_scene);
-        return;
-    }
-
-    m_sprite("/assets/title.png", ((Rect) {
-            ((float)ctx.resolution.x / 2) - ((float)320 / 2), 64, 320, 128 }));
-
-    /* draw the tick count as an example of dynamic text */
-    size_t text_str_len = snprintf(NULL, 0, "%llu", (unsigned long long)state->ctx->frame_number) + 1;
-    char *text_str = malloc(text_str_len);
-    snprintf(text_str, text_str_len, "%llu", (unsigned long long)state->ctx->frame_number);
-
-    const char *font = "/fonts/kenney-pixel.ttf";
-    float text_h = 32;
-    float text_w = draw_text_width(text_str, text_h, font);
-
-    draw_rectangle(
-        (Rect) {
-            .x = 0,
-            .y = 0,
-            .w = (float)text_w,
-            .h = (float)text_h,
-        },
-        (Color) { 0, 0, 0, 255 }
-    );
-
-    draw_text(text_str, (Vec2){ 0, 0 }, text_h, (Color) { 255, 255, 255, 255 }, font);
-    free(text_str);
-}
-
-
-static void title_end(State *state) {
-    free(state->scene);
-}
-
-
-Scene *title_scene(State *state) {
-    (void)state;
-
-    SceneTitle *new_scene = calloc(1, sizeof *new_scene);
-    new_scene->base.tick = title_tick;
-    new_scene->base.end = title_end;
-
-    return (Scene *)new_scene;
-}

apps/demos/scenery/scenes/title.h

@@ -1,16 +0,0 @@
-#ifndef TITLE_H
-#define TITLE_H
-
-#include "../state.h"
-#include "scene.h"
-
-
-typedef struct SceneTitle {
-    Scene base;
-} SceneTitle;
-
-
-Scene *title_scene(State *state);
-
-
-#endif

apps/examples/circle-raster/CMakeLists.txt

@@ -6,11 +6,11 @@ if(NOT CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
 
 set(SOURCE_FILES
         game.c
         state.h
 )
 
-use_townengine(${PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})
+use_townengine("${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/examples/circle-raster/game.c

@@ -103,7 +103,7 @@ static void benchmark(struct state *state) {
 void game_tick(void) {
     if (ctx.initialization_needed) {
         if (!ctx.udata) {
-            ctx.udata = ccalloc(1, sizeof (struct state));
+            ctx.udata = calloc(1, sizeof (struct state));
             struct state *state = ctx.udata;
             state->r = 24;
         }
@@ -113,14 +113,16 @@ void game_tick(void) {
 
     Vec2 const mouse_snap = {floorf(ctx.mouse_position.x / 8) * 8, floorf(ctx.mouse_position.y / 8) * 8};
 
-    input_action("up", CONTROL_LEFT_MOUSE);
+    input_action("up", "LCLICK");
-    input_action("down", CONTROL_RIGHT_MOUSE);
+    input_action("down", "RCLICK");
 
-    if (input_action_just_pressed("up"))
+    if (input_action_pressed("up"))
         state->r += 1;
-    if (input_action_just_pressed("down"))
+    if (input_action_pressed("down") && state->r > 2)
         state->r -= 1;
 
+    draw_circle(mouse_snap, state->r * 8, (Color){125, 125, 125, 125});
+
     int32_t const rsi = (int32_t)state->r * (int32_t)state->r;
     int32_t acc = 1;
     for (int32_t iy = (int32_t)state->r - 1; iy >= 0; --iy) {
@@ -133,9 +135,8 @@ void game_tick(void) {
         }
     }
 
-    draw_circle(mouse_snap, state->r * 8, (Color){125, 125, 125, 125});
+    /* uncomment to see performance difference between variants */
-
+    // benchmark(state);
-    benchmark(state);
 }
 
 

apps/template/CMakeLists.txt

@@ -1,16 +0,0 @@
-cmake_minimum_required(VERSION 3.21)
-
-project(template LANGUAGES C)
-
-if(NOT CMAKE_BUILD_TYPE)
-        set(CMAKE_BUILD_TYPE Debug)
-endif()
-
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
-
-set(SOURCE_FILES
-        game.c
-        state.h
-)
-
-use_townengine(${PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/templates/c/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.21)
+project(twngame LANGUAGES C)
+
+if(NOT CMAKE_BUILD_TYPE)
+        set(CMAKE_BUILD_TYPE Debug)
+endif()
+
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
+
+set(SOURCE_FILES
+        game.c
+        state.h
+)
+
+cmake_path(GET CMAKE_SOURCE_DIR STEM LAST_ONLY GAME_PROJECT_NAME)
+use_townengine("${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/templates/c/data/twn.toml

@@ -0,0 +1,27 @@
+# This file contains everything about the engine and your game that can be
+# configured before it runs.
+#
+# Optional settings are commented out, with their default values shown.
+# Invalid values in these settings will be ignored.
+
+# Data about your game as an application
+[about]
+title = "Template"
+developer = "You"
+app_id = "template"
+dev_id = "you"
+
+# Game runtime details
+[game]
+resolution = [ 640, 480 ]
+background_color = [ 255, 125, 0, 255 ]
+#debug = true
+
+# Engine tweaks. You probably don't need to change these
+[engine]
+#ticks_per_second = 60 # minimum of 8
+#keybind_slots = 3 # minimum of 1
+#texture_atlas_size = 2048 # minimum of 32
+#font_texture_size = 2048 # minimum of 1024
+#font_oversampling = 4 # minimum of 0
+#font_filtering = "linear" # possible values: "nearest", "linear"

apps/templates/c/game.c

@@ -1,7 +1,7 @@
 #include "twn_game_api.h"
 #include "state.h"
 
-#include <malloc.h>
+#include <stdlib.h>
 
 
 void game_tick(void) {
@@ -10,7 +10,7 @@ void game_tick(void) {
     if (ctx.initialization_needed) {
         /* application data could be stored in ctx.udata and retrieved anywhere */
         if (!ctx.udata)
-            ctx.udata = ccalloc(1, sizeof (struct state));
+            ctx.udata = calloc(1, sizeof (struct state));
     }
 
     /* a lot of data is accessible from `ctx`, look into `townengine/context.h` for more */

apps/templates/lua/.gitignore

@@ -0,0 +1,17 @@
+# ignore executables
+*
+!*.*
+!*/
+
+**/*.so
+**/*.dll
+**/*.exe
+**/*.trace
+**/*.js
+**/*.wasm
+**/*.wasm.map
+**/*.data
+**/*.html
+
+data/scripts/twnapi.lua
+build/

apps/templates/lua/data/scripts/game.lua

@@ -0,0 +1,7 @@
+-- called every frame, with constant delta time
+function game_tick()
+    -- ctx.udata persists on code reload
+    if ctx.udata == nil then
+        ctx.udata = {}
+    end
+end

apps/templates/lua/data/twn.toml

@@ -0,0 +1,27 @@
+# This file contains everything about the engine and your game that can be
+# configured before it runs.
+#
+# Optional settings are commented out, with their default values shown.
+# Invalid values in these settings will be ignored.
+
+# Data about your game as an application
+[about]
+title = "Template"
+developer = "You"
+app_id = "template"
+dev_id = "you"
+
+# Game runtime details
+[game]
+resolution = [ 640, 480 ]
+interpreter = "$TWNROOT/apps/twnlua"
+#debug = true
+
+# Engine tweaks. You probably don't need to change these
+[engine]
+#ticks_per_second = 60 # minimum of 8
+#keybind_slots = 3 # minimum of 1
+#texture_atlas_size = 2048 # minimum of 32
+#font_texture_size = 2048 # minimum of 1024
+#font_oversampling = 4 # minimum of 0
+#font_filtering = "linear" # possible values: "nearest", "linear"

apps/templates/zig/.gitignore

@@ -0,0 +1,19 @@
+# ignore executables
+*
+!*.*
+!*/
+
+**/*.so
+**/*.dll
+**/*.exe
+**/*.trace
+**/*.js
+**/*.wasm
+**/*.wasm.map
+**/*.data
+**/*.html
+
+data/scripts/twnapi.lua
+build/
+.zig-cache/
+zig-out/

apps/templates/zig/CMakeLists.txt

@@ -0,0 +1,26 @@
+cmake_minimum_required(VERSION 3.21)
+project(twngame LANGUAGES C)
+
+if(NOT CMAKE_BUILD_TYPE)
+        set(CMAKE_BUILD_TYPE Debug)
+endif()
+
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
+
+cmake_path(GET CMAKE_SOURCE_DIR STEM LAST_ONLY GAME_PROJECT_NAME)
+put_townengine(${CMAKE_CURRENT_SOURCE_DIR})
+
+file(GLOB_RECURSE zig-sources ${CMAKE_CURRENT_SOURCE_DIR}/src/*.zig)
+
+# TODO: support static build
+# TODO: propagate release switches
+add_custom_command(
+    OUTPUT ${CMAKE_CURRENT_SOURCE_DIR}/libgame.so
+    COMMAND env zig build
+    DEPENDS ${TWN_TARGET} ${zig-sources}
+)
+
+add_custom_target(
+    zig-step ALL
+    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libgame.so
+)

apps/templates/zig/build.zig

@@ -0,0 +1,58 @@
+const std = @import("std");
+
+// Although this function looks imperative, note that its job is to
+// declaratively construct a build graph that will be executed by an external
+// runner.
+pub fn build(b: *std.Build) void {
+    // Standard target options allows the person running `zig build` to choose
+    // what target to build for. Here we do not override the defaults, which
+    // means any target is allowed, and the default is native. Other options
+    // for restricting supported target set are available.
+    const target = b.standardTargetOptions(.{});
+
+    // Standard optimization options allow the person running `zig build` to select
+    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
+    // set a preferred release mode, allowing the user to decide how to optimize.
+    const optimize = b.standardOptimizeOption(.{});
+
+    // This creates a "module", which represents a collection of source files alongside
+    // some compilation options, such as optimization mode and linked system libraries.
+    // Every executable or library we compile will be based on one or more modules.
+    const lib_mod = b.createModule(.{
+        // `root_source_file` is the Zig "entry point" of the module. If a module
+        // only contains e.g. external object files, you can make this `null`.
+        // In this case the main source file is merely a path, however, in more
+        // complicated build scripts, this could be a generated file.
+        .root_source_file = b.path("src/root.zig"),
+        .target = target,
+        .optimize = optimize,
+        .link_libc = true,
+    });
+
+    lib_mod.addIncludePath(b.path("../../../"));
+    lib_mod.addIncludePath(b.path("../../../include/"));
+    lib_mod.addLibraryPath(b.path("./"));
+
+    // Now, we will create a static library based on the module we created above.
+    // This creates a `std.Build.Step.Compile`, which is the build step responsible
+    // for actually invoking the compiler.
+    const lib = b.addLibrary(.{
+        .linkage = .dynamic,
+        .name = "game",
+        .root_module = lib_mod,
+    });
+
+    lib.linkSystemLibrary("townengine");
+
+    // This declares intent for the library to be installed into the standard
+    // location when the user invokes the "install" step (the default step when
+    // running `zig build`).
+    const install_artifact = b.addInstallArtifact(lib, .{
+        .dest_dir = .{
+            .override = .{
+                .custom = "../",
+            },
+        },
+    });
+    b.getInstallStep().dependOn(&install_artifact.step);
+}

apps/templates/zig/data/twn.toml

@@ -0,0 +1,27 @@
+# This file contains everything about the engine and your game that can be
+# configured before it runs.
+#
+# Optional settings are commented out, with their default values shown.
+# Invalid values in these settings will be ignored.
+
+# Data about your game as an application
+[about]
+title = "Zig Awesomeness"
+developer = "notwanp"
+app_id = "yourzigthing"
+dev_id = "definatelynotwanp"
+
+# Game runtime details
+[game]
+resolution = [ 640, 480 ]
+background_color = [ 255, 125, 0, 255 ]
+#debug = true
+
+# Engine tweaks. You probably don't need to change these
+[engine]
+#ticks_per_second = 60 # minimum of 8
+#keybind_slots = 3 # minimum of 1
+#texture_atlas_size = 2048 # minimum of 32
+#font_texture_size = 2048 # minimum of 1024
+#font_oversampling = 4 # minimum of 0
+#font_filtering = "linear" # possible values: "nearest", "linear"

apps/templates/zig/src/root.zig

@@ -0,0 +1,24 @@
+const std = @import("std");
+const c = @cImport({
+    @cInclude("twn_game_api.h");
+});
+
+export fn game_tick() void {
+    tick() catch |err| {
+        std.log.err(@errorName(err));
+    };
+}
+
+export fn game_end() void {
+    end() catch |err| {
+        std.log.err(@errorName(err));
+    };
+}
+
+fn tick() !void {
+    if (c.ctx.initialization_needed) {
+        std.debug.print("lmao\n", .{});
+    }
+}
+
+fn end() !void {}

apps/tools/twndel/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.21)
+project(twndel LANGUAGES C)
+
+if(NOT CMAKE_BUILD_TYPE)
+        set(CMAKE_BUILD_TYPE Debug)
+endif()
+
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
+
+set(SOURCE_FILES
+        tool.c
+        state.h
+)
+
+cmake_path(GET CMAKE_SOURCE_DIR STEM LAST_ONLY GAME_PROJECT_NAME)
+use_townengine("${SOURCE_FILES}" ${CMAKE_CURRENT_SOURCE_DIR})

apps/tools/twndel/data/twn.toml

@@ -0,0 +1,12 @@
+[about]
+title = "Townengine Modeling Tool"
+developer = "twnteam"
+app_id = "twndel"
+dev_id = "twnteam"
+
+# Game runtime details
+[game]
+resolution = [ 640, 480 ]
+background_color = [ 255, 125, 0, 255 ]
+
+[engine]

apps/tools/twndel/state.h

@@ -0,0 +1,118 @@
+#ifndef STATE_H
+#define STATE_H
+
+#include "twn_game_api.h"
+
+
+#define POINTS_PER_METER 128
+#define UNDO_STACK_SIZE 32
+#define CAMERA_FOV ((float)M_PI_2 * 0.75f)
+
+#define POINT_LIMIT 65534
+#define FACE_LIMIT 2048
+#define OBJECT_LIMIT 16
+#define TEXTURE_LIMIT 32
+
+#define INVALID_POINT (POINT_LIMIT+1)
+#define INVALID_FACE (FACE_LIMIT+1)
+#define INVALID_OBJECT (OBJECT_LIMIT+1)
+#define INVALID_TEXTURE (TEXTURE_LIMIT+1)
+
+#define CAMERA_ROTATION_SPEED 0.04f
+#define CAMERA_TRANSLATION_SPEED 0.04f
+#define SELECTION_SPHERE_RADIUS 32
+/* should be an odd number */
+#define SNAP_LINES_SHOW 7
+#define SNAP_LINES_WIDTH 1.0f
+#define SNAP_LINES_COLOR ((Color){200,200,200,150})
+
+typedef struct Operation {
+    enum {
+        OPERATION_MOVE_POINT,
+        OPERATION_SET_TEXTURE,
+        OPERATION_TRIANGULATE,
+    } kind;
+    union {
+        struct {
+            uint16_t point;
+            int16_t delta_x;
+            int16_t delta_y;
+            int16_t delta_z;
+            uint8_t object;
+        } move_point;
+
+        struct {
+            uint16_t face;
+            int16_t delta_texture;
+            uint8_t object;
+        } set_texture;
+
+        struct {
+            uint16_t old_face;
+            uint16_t new_face;
+            uint8_t object;
+        } triangulate;
+    } data;
+
+    bool chained;
+} Operation;
+
+typedef struct Point {
+    int16_t x, y, z;
+} Point;
+
+/* TODO: store topology in terms on edge connections? might be bad, as it's stateful */
+/* triangles have p3 = INVALID_POINT */
+/* lines have p2, p3 = INVALID_POINT */
+/* billboards have p1, p2, p3 = INVALID_POINT */
+typedef struct Face {
+    uint16_t p[4];
+    /* texture origin, as point on face plane, in absolute coordinates */
+    int16_t tex_x, tex_y;
+    uint8_t texture;
+    uint8_t tex_scale;
+} Face;
+
+typedef struct Object {
+    char *name;
+    bool is_invisible;
+    Point position;
+    char *textures[TEXTURE_LIMIT + 1];
+    uint8_t textures_sz;
+    Point rotation;
+    Face faces[FACE_LIMIT];
+    uint16_t faces_sz;
+} Object;
+
+typedef struct State {
+    Operation op_stack[UNDO_STACK_SIZE];
+    uint32_t op_stack_ptr;
+    bool op_active;
+
+    Vec3 active_center;
+    Vec3 camera_position;
+    Vec3 camera_direction;
+    float camera_zoom;
+    bool camera_is_orthographic;
+    /* defaults to wireframe */
+    bool solid_display_mode;
+    /* positions skipped */
+    uint8_t grid_snap_granularity;
+
+    Point points[POINT_LIMIT];
+    uint16_t points_sz;
+
+    Object objects[OBJECT_LIMIT];
+    uint8_t objects_sz;
+
+    /* which axes are blocked and which are not */
+    /* order: x, y, z */
+    bool axis_mask[3];
+    char *current_texture;
+
+    uint8_t current_hovered_obj;
+    uint16_t current_hovered_face;
+} State;
+
+
+#endif

apps/tools/twndel/tool.c

@@ -0,0 +1,972 @@
+#include "twn_game_api.h"
+#include "state.h"
+#include "twn_vec.h"
+
+#include <SDL.h>
+
+/* planned features: */
+/* grid-based, bounded space (65536 / POINTS_PER_METER meters), which allows for efficient storage */
+/* 65534 point limit, 16 object limit, 2048 faces per object, 32 textures per object */
+/* triangles and quads only */
+/* support for billboards and flat two sided quads */
+/* texture painting */
+/* bones with mesh animations, snapping to grid, with no weights */
+/* billboard render to specified angles */
+/* 1 point light primitive lighting */
+/* live edited textures are capped at 128x128 */
+
+/* assumptions: */
+/* up is always (0,1,0) */
+/* preallocations everywhere */
+
+static State state;
+static bool init;
+
+
+static uint8_t new_object(const char *name) {
+    if (state.objects_sz >= OBJECT_LIMIT)
+        return INVALID_OBJECT;
+    state.objects_sz++;
+    state.objects[state.objects_sz-1].name = SDL_strdup(name);
+    return state.objects_sz-1;
+}
+
+
+static uint16_t new_point(int16_t x, int16_t y, int16_t z) {
+    if (state.points_sz >= POINT_LIMIT)
+        return INVALID_POINT;
+    state.points_sz++;
+    state.points[state.points_sz-1] = (Point){x, y, z};
+    return state.points_sz-1;
+}
+
+
+static uint16_t push_face(uint8_t object,
+                          uint16_t p0, uint16_t p1, uint16_t p2, uint16_t p3,
+                          uint8_t texture, uint8_t tex_scale, int16_t tex_x, int16_t tex_y)
+{
+    Object *o = &state.objects[object];
+    o->faces_sz++;
+    o->faces[o->faces_sz-1] = (Face) {
+        .p = {p0, p1, p2, p3},
+        .texture = texture,
+        .tex_scale = tex_scale,
+        .tex_x = tex_x,
+        .tex_y = tex_y,
+    };
+    return o->faces_sz-1;
+}
+
+
+static uint8_t push_texture(uint8_t object, char *texture) {
+    Object *o = &state.objects[object];
+
+    /* check whether it's already here */
+    for (uint8_t i = 0; i < o->textures_sz; ++i)
+        if (SDL_strcmp(o->textures[i], texture) == 0)
+            return i;
+
+    o->textures_sz++;
+    o->textures[o->textures_sz-1] = SDL_strdup(texture);
+    return o->textures_sz-1;
+}
+
+
+/* TODO: use tombstones instead? it would be easier to maintain, by a lot */
+/* note: make sure nothing depends on none */
+static void pop_face(uint8_t object, uint16_t face) {
+    Object *o = &state.objects[object];
+    if (face != o->faces_sz-1)
+        o->faces[face] = o->faces[o->faces_sz-1];
+    o->faces_sz--;
+}
+
+
+
+static void push_operation(Operation operation, bool active) {
+    state.op_stack_ptr++;
+    uint8_t op = state.op_stack_ptr % UNDO_STACK_SIZE;
+    state.op_stack[op] = operation;
+    state.op_active = active;
+}
+
+
+static void extend_operation(Operation operation) {
+    uint8_t op = state.op_stack_ptr % UNDO_STACK_SIZE;
+    Operation ext = state.op_stack[op];
+    ext.chained = true;
+    state.op_stack[op] = operation;
+    push_operation(ext, state.op_active);
+}
+
+
+static inline Vec3 point_to_vec3(uint8_t object, uint16_t point) {
+    Object *o = &state.objects[object];
+    return (Vec3){ (o->position.x + state.points[point].x) / (float)POINTS_PER_METER,
+                   (o->position.y + state.points[point].y) / (float)POINTS_PER_METER,
+                   (o->position.z + state.points[point].z) / (float)POINTS_PER_METER };
+}
+
+
+/* TODO: something is wrong, figure out how to introduce rotation to this. */
+static inline Vec2 project_texture_coordinate(Vec2 origin, Vec3 plane, Vec3 point, float scale) {
+    Vec3 right = vec3_norm(vec3_cross(plane, fabsf(0.0f - plane.y) < 1e-9f ? (Vec3){0,1,0} : (Vec3){1,0,0}));
+    Vec3 up = vec3_norm(vec3_cross(right, plane));
+    Vec2 pp = { vec3_dot(point, right), vec3_dot(point, up) };
+    return vec2_scale(vec2_sub(origin, pp), scale);
+}
+
+
+static void render_object(uint8_t object) {
+    Object *o = &state.objects[object];
+
+    if (o->is_invisible)
+        return;
+
+    for (uint16_t fi = 0; fi < o->faces_sz; ++fi) {
+        Face *f = &o->faces[fi];
+
+        if (f->p[2] != INVALID_POINT) {
+            Vec3 p0 = point_to_vec3(object, f->p[0]);
+            Vec3 p1 = point_to_vec3(object, f->p[1]);
+            Vec3 p2 = point_to_vec3(object, f->p[2]);
+
+            if (state.solid_display_mode) {
+                Vec3 n = vec3_norm(vec3_cross(vec3_sub(p1, p0), vec3_sub(p2, p0)));
+                Vec2 to = { f->tex_x / (float)POINTS_PER_METER, f->tex_y / (float)POINTS_PER_METER, };
+
+                Vec2 tul = project_texture_coordinate(to, n, p0, (float)f->tex_scale);
+                Vec2 tdl = project_texture_coordinate(to, n, p1, (float)f->tex_scale);
+                Vec2 tdr = project_texture_coordinate(to, n, p2, (float)f->tex_scale);
+
+                draw_triangle(o->textures[f->texture],
+                              p0, p1, p2,
+                              tul, tdl, tdr,
+                              (Color){255,255,255,255},
+                              (Color){255,255,255,255},
+                              (Color){255,255,255,255});
+
+                if (f->p[3] != INVALID_POINT) {
+                    Vec3 p3 = point_to_vec3(object, f->p[3]);
+                    Vec2 tur = project_texture_coordinate(to, n, p3, (float)f->tex_scale);
+                    draw_triangle(o->textures[f->texture],
+                                  p2, p3, p0,
+                                  tdr, tur, tul,
+                                  (Color){255,255,255,255},
+                                  (Color){255,255,255,255},
+                                  (Color){255,255,255,255});
+                }
+
+            } else {
+                draw_line_3d(p0, p1, 1, (Color){255,255,255,255});
+                draw_line_3d(p1, p2, 1, (Color){255,255,255,255});
+
+                if (f->p[3] == INVALID_POINT)
+                    draw_line_3d(p2, p0, 1, (Color){255,255,255,255});
+                else {
+                    Vec3 p3 = point_to_vec3(object, f->p[3]);
+                    draw_line_3d(p2, p3, 1, (Color){255,255,255,255});
+                    draw_line_3d(p3, p0, 1, (Color){255,255,255,255});
+                }
+            }
+
+        } else
+            SDL_assert_always(false);
+    }
+}
+
+
+static uint8_t new_cube(Point pos, Point size) {
+    uint8_t object = new_object("cube");
+
+    uint16_t p0 = new_point(pos.x - size.x / 2, pos.y - size.y / 2, pos.z - size.z / 2);
+    uint16_t p1 = new_point(pos.x - size.x / 2, pos.y + size.y / 2, pos.z - size.z / 2);
+    uint16_t p2 = new_point(pos.x + size.x / 2, pos.y + size.y / 2, pos.z - size.z / 2);
+    uint16_t p3 = new_point(pos.x + size.x / 2, pos.y - size.y / 2, pos.z - size.z / 2);
+    uint16_t p4 = new_point(pos.x - size.x / 2, pos.y - size.y / 2, pos.z + size.z / 2);
+    uint16_t p5 = new_point(pos.x - size.x / 2, pos.y + size.y / 2, pos.z + size.z / 2);
+    uint16_t p6 = new_point(pos.x + size.x / 2, pos.y + size.y / 2, pos.z + size.z / 2);
+    uint16_t p7 = new_point(pos.x + size.x / 2, pos.y - size.y / 2, pos.z + size.z / 2);
+
+    uint8_t tex = push_texture(object, "/data/placeholder.png");
+    push_face(object, p2, p3, p0, p1, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+    push_face(object, p5, p4, p7, p6, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+    push_face(object, p1, p0, p4, p5, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+    push_face(object, p6, p7, p3, p2, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+    push_face(object, p2, p1, p5, p6, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+    push_face(object, p0, p3, p7, p4, tex, 128, pos.x - size.x / 2, pos.y - size.y / 2);
+
+    return object;
+}
+
+
+static void process_camera_rotation(void) {
+    float horizontal_rotation = 0;
+    float vertical_rotation = 0;
+
+    if (input_action_pressed("camera_rotate_left"))
+        horizontal_rotation -= CAMERA_ROTATION_SPEED;
+    if (input_action_pressed("camera_rotate_right"))
+        horizontal_rotation += CAMERA_ROTATION_SPEED;
+    if (input_action_pressed("camera_rotate_up"))
+        vertical_rotation -= CAMERA_ROTATION_SPEED;
+    if (input_action_pressed("camera_rotate_down"))
+        vertical_rotation += CAMERA_ROTATION_SPEED;
+
+    Vec3 front = vec3_cross(state.camera_direction, (Vec3){0,1,0});
+    Vec3 local_position = vec3_sub(state.active_center, state.camera_position);
+    Vec3 new_local_position = vec3_rotate(local_position, horizontal_rotation, (Vec3){0,1,0});
+
+    state.camera_direction = vec3_rotate(state.camera_direction, horizontal_rotation, (Vec3){0,1,0});
+    Vec3 new_rot = vec3_rotate(state.camera_direction, vertical_rotation, front);
+
+    /* only apply if it's in limits */
+    float d = vec3_dot(new_rot, (Vec3){0,-1,0});
+    if (fabsf(d) <= 0.999f) {
+        new_local_position = vec3_rotate(new_local_position, vertical_rotation, front);
+        state.camera_direction = new_rot;
+    }
+
+    state.camera_position = vec3_sub(state.active_center, new_local_position);
+}
+
+
+static void process_camera_translation(void) {
+    Vec3 right = vec3_norm(vec3_cross(state.camera_direction, (Vec3){0,1,0}));
+    Vec3 up = vec3_norm(vec3_cross(state.camera_direction, right));
+    Vec3 was = state.camera_position;
+
+    if (input_action_pressed("camera_rotate_left"))
+        state.camera_position = vec3_sub(state.camera_position, vec3_scale(right, CAMERA_TRANSLATION_SPEED));
+    if (input_action_pressed("camera_rotate_right"))
+        state.camera_position = vec3_add(state.camera_position, vec3_scale(right, CAMERA_TRANSLATION_SPEED));
+    if (input_action_pressed("camera_rotate_up"))
+        state.camera_position = vec3_sub(state.camera_position, vec3_scale(up, CAMERA_TRANSLATION_SPEED));
+    if (input_action_pressed("camera_rotate_down"))
+        state.camera_position = vec3_add(state.camera_position, vec3_scale(up, CAMERA_TRANSLATION_SPEED));
+
+    state.active_center = vec3_add(state.active_center, vec3_sub(state.camera_position, was));
+
+    draw_billboard("/data/camera.png",
+                    vec3_add(state.camera_position, vec3_scale(state.camera_direction, vec3_length(state.camera_position))),
+                    (Vec2){0.2f,0.2f},
+                    (Rect){0},
+                    (Color){255,255,255,255},
+                    false);
+
+    /* show relation to origin */
+    draw_billboard("/data/center.png",
+                    (Vec3){0},
+                    (Vec2){0.1f,0.1f},
+                    (Rect){0},
+                    (Color){255,255,255,255},
+                    false);
+
+    draw_line_3d((Vec3){0}, state.active_center, 1, (Color){255,255,255,255});
+}
+
+
+static void process_camera_movement(void) {
+    input_action("camera_rotate_left", "A");
+    input_action("camera_rotate_right", "D");
+    input_action("camera_rotate_up", "W");
+    input_action("camera_rotate_down", "S");
+    input_action("camera_lock_rotation", "SPACE");
+
+    if (input_action_pressed("camera_lock_rotation")) {
+        process_camera_translation();
+    } else {
+        process_camera_rotation();
+    }
+}
+
+
+static inline DrawCameraUnprojectResult unproject_point(Vec2 point) {
+    return draw_camera_unproject(
+        point,
+        state.camera_position,
+        state.camera_direction,
+        (Vec3){0, 1, 0},
+        state.camera_is_orthographic ? 0 : CAMERA_FOV,
+        state.camera_zoom,
+        100 );
+}
+
+
+static bool find_closest_point(uint8_t* object_result, uint16_t *point_result) {
+    DrawCameraUnprojectResult pos_and_ray = unproject_point(ctx.mouse_position);
+
+    /* step over every selectable object and find points closest to the view ray */
+    /* by constructing triangles and finding their height, from perpendicular */
+    uint16_t closest_point = INVALID_POINT;
+    uint8_t closest_obj = INVALID_OBJECT;
+    float closest_distance = INFINITY;
+
+    for (uint8_t obj = 0; obj < state.objects_sz; ++obj) {
+        Object *o = &state.objects[obj];
+
+        if (o->is_invisible)
+            continue;
+
+        /* TODO: is it possible to skip repeated points? does it matter? */
+        /*       as we limit the point could we could actually have bool array preallocated for this */
+        for (uint16_t fi = 0; fi < o->faces_sz; ++fi) {
+            Face *f = &o->faces[fi];
+            for (uint16_t pi = 0; pi < 4; ++pi) {
+                if (f->p[pi] == INVALID_POINT) break;
+                Vec3 p = point_to_vec3(obj, f->p[pi]);
+                Vec3 d = vec3_sub(pos_and_ray.position, p);
+                Vec3 b = vec3_cross(d, pos_and_ray.direction);
+                float ray_dist = vec3_length(b);
+                if (ray_dist > ((float)SELECTION_SPHERE_RADIUS / POINTS_PER_METER))
+                    continue;
+                float dist = vec3_length(vec3_sub(pos_and_ray.position, vec3_add(p, b)));
+                if (dist < closest_distance) {
+                    closest_distance = dist;
+                    closest_obj = obj;
+                    closest_point = f->p[pi];
+                }
+            }
+        }
+    }
+
+    if (closest_point == INVALID_POINT)
+        return false;
+
+    if (object_result)
+        *object_result = closest_obj;
+    if (point_result)
+        *point_result = closest_point;
+
+    return true;
+}
+
+
+/* o = vector origin */
+/* v = vector direction, normalized */
+/* p = any point on plane */
+/* n = normal of a plane */
+static bool vector_plane_intersection(Vec3 o, Vec3 v, Vec3 p, Vec3 n, Vec3 *out) {
+    float dot = vec3_dot(n, v);
+    if (fabsf(dot) > FLT_EPSILON) {
+        Vec3 w = vec3_sub(o, p);
+        float fac = -vec3_dot(n, w) / dot;
+        *out = vec3_add(o, vec3_scale(v, fac));
+        return true;
+    }
+    /* vector and plane are perpendicular, assume that it lies exactly on it */
+    return false;
+}
+
+
+static bool find_closest_face(uint8_t* object_result, uint16_t *face_result) {
+    DrawCameraUnprojectResult cam = unproject_point(ctx.mouse_position);
+
+    uint8_t closest_obj = INVALID_OBJECT;
+    uint16_t closest_face = INVALID_FACE;
+    float closest_distance = INFINITY;
+
+    for (uint8_t oi = 0; oi < state.objects_sz; ++oi) {
+        Object *o = &state.objects[oi];
+        for (uint16_t fi = 0; fi < o->faces_sz; ++fi) {
+            Face *f = &o->faces[fi];
+
+            if (f->p[1] == INVALID_POINT) continue;
+
+            Vec3 p0 = point_to_vec3(oi, f->p[0]);
+            Vec3 p1 = point_to_vec3(oi, f->p[1]);
+            Vec3 p2 = point_to_vec3(oi, f->p[2]);
+
+            Vec3 n = vec3_norm(vec3_cross(vec3_sub(p1, p0), vec3_sub(p2, p0)));
+
+            /* culling */
+            if (vec3_dot(state.camera_direction, n) >= 0) continue;
+
+            Vec3 i;
+            if (!vector_plane_intersection(cam.position, cam.direction, p0, n, &i))
+                continue;
+
+            float dist = vec3_length(vec3_sub(p0, i));
+            if (dist >= closest_distance) continue;
+
+            /* left normals are used to determine whether point lies to the left for all forming lines */
+            Vec3 ln0 = vec3_norm(vec3_cross(n, vec3_sub(p1, p0)));
+            if (vec3_dot(ln0, vec3_sub(p0, i)) >= 0) continue;
+
+            Vec3 ln1 = vec3_norm(vec3_cross(n, vec3_sub(p2, p1)));
+            if (vec3_dot(ln1, vec3_sub(p1, i)) >= 0) continue;
+
+            if (f->p[3] == INVALID_POINT) {
+                /* triangle */
+                Vec3 ln2 = vec3_norm(vec3_cross(n, vec3_sub(p0, p2)));
+                if (vec3_dot(ln2, vec3_sub(p2, i)) >= 0) continue;
+
+            } else {
+                /* quad */
+                Vec3 p3 = point_to_vec3(oi, f->p[3]);
+                Vec3 ln2 = vec3_norm(vec3_cross(n, vec3_sub(p3, p2)));
+                if (vec3_dot(ln2, vec3_sub(p2, i)) >= 0) continue;
+
+                Vec3 ln3 = vec3_norm(vec3_cross(n, vec3_sub(p0, p3)));
+                if (vec3_dot(ln3, vec3_sub(p3, i)) >= 0) continue;
+            }
+
+            closest_distance = dist;
+            closest_face = fi;
+            closest_obj = oi;
+        }
+    }
+
+    if (closest_face == INVALID_FACE)
+        return false;
+
+    if (object_result)
+        *object_result = closest_obj;
+    if (face_result)
+        *face_result = closest_face;
+
+    return true;
+}
+
+
+static void show_snap_lines(Vec3 p) {
+    float step = 1.0f / ((float)POINTS_PER_METER / state.grid_snap_granularity);
+    int const lines_per_side = (SNAP_LINES_SHOW - 1) / 2;
+
+    for (int l = -lines_per_side; l <= lines_per_side; ++l) {
+        if (!state.axis_mask[0]) {
+            Vec3 c = vec3_add(p, vec3_scale((Vec3){1,0,0}, step * (float)l));
+            draw_line_3d(
+                vec3_add(c, vec3_scale((Vec3){0,0,1},  SNAP_LINES_WIDTH)),
+                vec3_add(c, vec3_scale((Vec3){0,0,1}, -SNAP_LINES_WIDTH)),
+                1,
+                SNAP_LINES_COLOR);
+        }
+
+        if (!state.axis_mask[1]) {
+            Vec3 axis = fabsf(vec3_dot(state.camera_direction, (Vec3){0,0,1})) >= 0.5f ? (Vec3){1,0,0} : (Vec3){0,0,1};
+            Vec3 c = vec3_add(p, vec3_scale((Vec3){0,1,0}, step * (float)l));
+            draw_line_3d(
+                vec3_add(c, vec3_scale(axis,  SNAP_LINES_WIDTH)),
+                vec3_add(c, vec3_scale(axis, -SNAP_LINES_WIDTH)),
+                1,
+                SNAP_LINES_COLOR);
+        }
+
+        if (!state.axis_mask[2]) {
+            Vec3 c = vec3_add(p, vec3_scale((Vec3){0,0,1}, step * (float)l));
+            draw_line_3d(
+                vec3_add(c, vec3_scale((Vec3){1,0,0},  SNAP_LINES_WIDTH)),
+                vec3_add(c, vec3_scale((Vec3){1,0,0}, -SNAP_LINES_WIDTH)),
+                1,
+                SNAP_LINES_COLOR);
+        }
+    }
+}
+
+
+static bool process_operation_move_point(Operation *op) {
+    /* finish dragging around */
+    /* TODO: dont keep empty ops on stack? */
+    if (input_action_just_released("select")) {
+        state.op_active = false;
+        return false;
+    }
+
+    float size = sinf(ctx.frame_number / 10) * 0.05f + 0.05f;
+    draw_billboard("/data/grab.png",
+                   point_to_vec3(op->data.move_point.object, op->data.move_point.point),
+                   (Vec2){size, size},
+                   (Rect){0},
+                   (Color){255,255,255,255},
+                   false);
+
+    DrawCameraUnprojectResult cam = unproject_point(ctx.mouse_position);
+    Vec3 p = point_to_vec3(op->data.move_point.object, op->data.move_point.point);
+    bool point_moved = false;
+
+    /* figure out which planes are angled acutely against the viewing direction */
+    bool y_closer_than_horizon = fabsf(vec3_dot(state.camera_direction, (Vec3){0,1,0})) >= 0.5f;
+
+    Vec3 plane_normal_x = y_closer_than_horizon ? (Vec3){0,1,0} : (Vec3){0,0,1};
+    Vec3 plane_normal_z = y_closer_than_horizon ? (Vec3){0,1,0} : (Vec3){1,0,0};
+
+    /* show snapping in lines */
+    show_snap_lines(p);
+
+    Vec3 s;
+    if (!state.axis_mask[0]) {
+        if (vector_plane_intersection(cam.position, cam.direction, p, plane_normal_x, &s)) {
+            int16_t xch = (int16_t)(roundf(vec3_dot(vec3_sub(s, p), (Vec3){1,0,0}) * (float)POINTS_PER_METER));
+            xch -= xch % state.grid_snap_granularity;
+            state.points[op->data.move_point.point].x += xch;
+            op->data.move_point.delta_x += xch;
+            if (xch != 0) point_moved = true;
+        }
+    }
+
+    if (!state.axis_mask[1]) {
+        if (vector_plane_intersection(cam.position, cam.direction, p, (Vec3){0,0,1}, &s)) {
+            int16_t ych = (int16_t)(roundf(vec3_dot(vec3_sub(s, p), (Vec3){0,1,0}) * (float)POINTS_PER_METER));
+            ych -= ych % state.grid_snap_granularity;
+            state.points[op->data.move_point.point].y += ych;
+            op->data.move_point.delta_y += ych;
+            if (ych != 0) point_moved = true;
+        }
+    }
+
+    if (!state.axis_mask[2]) {
+        if (vector_plane_intersection(cam.position, cam.direction, p, plane_normal_z, &s)) {
+            int16_t zch = (int16_t)(roundf(vec3_dot(vec3_sub(s, p), (Vec3){0,0,1}) * (float)POINTS_PER_METER));
+            zch -= zch % state.grid_snap_granularity;
+            state.points[op->data.move_point.point].z += zch;
+            op->data.move_point.delta_z += zch;
+            if (zch != 0) point_moved = true;
+        }
+    }
+
+    if (point_moved) {
+        audio_play("/data/bong.ogg", NULL, false, 0.12f, 0.0f);
+        return true;
+    }
+
+    return false;
+}
+
+
+static void reverse_operation_move_point(Operation *op) {
+    SDL_assert(op->kind == OPERATION_MOVE_POINT);
+    state.points[op->data.move_point.point].x -= op->data.move_point.delta_x;
+    state.points[op->data.move_point.point].y -= op->data.move_point.delta_y;
+    state.points[op->data.move_point.point].z -= op->data.move_point.delta_z;
+    audio_play("/data/drop.ogg", NULL, false, 0.4f, 0.0f);
+}
+
+
+static void reverse_operation_set_texture(Operation *op) {
+    SDL_assert(op->kind == OPERATION_SET_TEXTURE);
+    Object *o = &state.objects[op->data.set_texture.object];
+    o->faces[op->data.set_texture.face].texture += op->data.set_texture.delta_texture;
+    audio_play("/data/drop.ogg", NULL, false, 0.4f, 0.0f);
+}
+
+
+static void reverse_triangulation(Operation *op) {
+    SDL_assert(op->kind == OPERATION_TRIANGULATE);
+    Object *o = &state.objects[op->data.set_texture.object];
+    Face *fn = &o->faces[op->data.triangulate.new_face];
+    Face *fo = &o->faces[op->data.triangulate.old_face];
+    fo->p[3] = fo->p[2];
+    fo->p[2] = fn->p[1];
+    pop_face(op->data.set_texture.object, op->data.triangulate.new_face);
+}
+
+
+/* TODO: reverse of this */
+static void try_subdividing_from_moving(uint8_t object, uint16_t point) {
+    Object *o = &state.objects[object];
+    bool not_first = false;
+
+    for (uint16_t fi = 0; fi < o->faces_sz; ++fi) {
+        Face *f = &o->faces[fi];
+        if (f->p[3] == INVALID_POINT) continue;
+        for (uint16_t pi = 0; pi < 4; ++pi) {
+            if (f->p[pi] == point) {
+                Face new0 = *f;
+                new0.p[0] = f->p[pi];
+                new0.p[1] = f->p[(pi + 1) % 4];
+                new0.p[2] = f->p[(pi + 3) % 4];
+                new0.p[3] = INVALID_POINT;
+
+                uint16_t newf = push_face(
+                    object,
+                    f->p[(pi + 1) % 4],
+                    f->p[(pi + 2) % 4],
+                    f->p[(pi + 3) % 4],
+                    INVALID_POINT,
+                    f->texture,
+                    f->tex_scale,
+                    f->tex_x,
+                    f->tex_y);
+
+                *f = new0;
+
+                extend_operation((Operation){
+                    .kind = OPERATION_TRIANGULATE,
+                    .data = { .triangulate = { .new_face =  newf, .old_face = fi, .object = object} },
+                    .chained = not_first,
+                });
+
+                not_first = true;
+            }
+        }
+    }
+}
+
+
+static void process_undo(void) {
+    if (state.op_active)
+        state.op_active = false;
+
+    /* TODO: checks and defined limit */
+    Operation *op = &state.op_stack[state.op_stack_ptr % UNDO_STACK_SIZE];
+    state.op_stack_ptr--;
+
+    switch (op->kind) {
+    case OPERATION_MOVE_POINT: {
+        reverse_operation_move_point(op);
+        break;
+    }
+
+    case OPERATION_SET_TEXTURE: {
+        reverse_operation_set_texture(op);
+        break;
+    }
+
+    case OPERATION_TRIANGULATE: {
+        reverse_triangulation(op);
+        break;
+    }
+
+    default:
+        (void)0;
+    }
+
+    /* pop another if they're chained together */
+    if (op->chained) process_undo();
+}
+
+
+static void process_operations(void) {
+    if (input_action_just_pressed("undo"))
+        process_undo();
+
+    if (!state.op_active) {
+        /* point dragging */
+        if (!state.current_texture) {
+            uint16_t point_select; uint8_t obj_select;
+            if (find_closest_point(&obj_select, &point_select)) {
+                draw_billboard("/data/point.png",
+                               point_to_vec3(obj_select, point_select),
+                               (Vec2){0.05f, 0.05f},
+                               (Rect){0},
+                               (Color){255,255,255,255},
+                               false);
+
+                if (input_action_just_pressed("select"))
+                    push_operation((Operation){
+                        .kind = OPERATION_MOVE_POINT,
+                        .data = { .move_point = { .point = point_select, .object = obj_select } },
+                    }, true );
+            }
+
+        /* texture setting */
+        } else {
+            uint8_t obj_select; uint16_t face_select;
+            if (find_closest_face(&obj_select, &face_select)) {
+                state.current_hovered_face = face_select;
+                state.current_hovered_obj = obj_select;
+
+                if (input_action_just_pressed("rotate")) {
+                    Face *f = &state.objects[obj_select].faces[face_select];
+                    int16_t tex_x = f->tex_x;
+                    int16_t tex_y = f->tex_y;
+                    f->tex_x = -tex_y;
+                    f->tex_y = tex_x;
+                }
+
+                if (input_action_pressed("select") && state.current_texture) {
+                    uint8_t new_tex = push_texture(obj_select, state.current_texture);
+                    uint8_t cur_tex = state.objects[obj_select].faces[face_select].texture;
+
+                    if (new_tex != cur_tex) {
+                        state.objects[obj_select].faces[face_select].texture = new_tex;
+                        audio_play("/data/bong.ogg", NULL, false, 0.5f, 0.0f);
+
+                        push_operation((Operation){
+                            .kind = OPERATION_SET_TEXTURE,
+                            .data = { .set_texture = {
+                                .face = face_select,
+                                .object = obj_select,
+                                .delta_texture = cur_tex - new_tex,
+                            }},
+                        }, false );
+                    }
+                }
+            }
+        }
+    }
+
+    if (state.op_active) {
+        Operation *op = &state.op_stack[state.op_stack_ptr % UNDO_STACK_SIZE];
+        switch (op->kind) {
+        case OPERATION_MOVE_POINT: {
+            bool update = process_operation_move_point(op);
+
+            if (update)
+                try_subdividing_from_moving(op->data.move_point.object, op->data.move_point.point);
+
+            break;
+        }
+
+        case OPERATION_SET_TEXTURE:
+        case OPERATION_TRIANGULATE:
+        default:
+            (void)0;
+        }
+    }
+}
+
+
+static void draw_axes(void) {
+    /* axis helpers */
+    /* idea: double selection of axes for diagonal edits */
+    draw_line_3d(state.active_center, (Vec3){256,0,0}, 1, state.axis_mask[0] ? (Color){0,0,0,75} : (Color){255,0,0,125});
+    draw_billboard("/data/x.png",
+                   vec3_add(state.active_center, (Vec3){2,0,0}),
+                   (Vec2){0.1f, 0.1f},
+                   (Rect){0},
+                   state.axis_mask[0] ? (Color){0,0,0,255} : (Color){255,0,0,255},
+                   false);
+
+    draw_line_3d(state.active_center, (Vec3){0,256,0}, 1, state.axis_mask[1] ? (Color){0,0,0,75} : (Color){75,125,25,125});
+    draw_billboard("/data/y.png",
+                   vec3_add(state.active_center, (Vec3){0,1.5f,0}),
+                   (Vec2){0.1f, 0.1f},
+                   (Rect){0},
+                   state.axis_mask[1] ? (Color){0,0,0,255} : (Color){75,125,25,255},
+                   false);
+
+    draw_line_3d(state.active_center, (Vec3){0,0,256}, 1, state.axis_mask[2] ? (Color){0,0,0,75} : (Color){0,0,255,125});
+    draw_billboard("/data/z.png",
+                   vec3_add(state.active_center, (Vec3){0,0,2}),
+                   (Vec2){0.1f, 0.1f},
+                   (Rect){0},
+                   state.axis_mask[2] ? (Color){0,0,0,255} : (Color){0,0,255,255},
+                   false);
+}
+
+
+static void draw_hovered_face_border(void) {
+    if (state.current_hovered_obj == INVALID_OBJECT || state.current_hovered_face == INVALID_FACE)
+        return;
+
+    Object *o = &state.objects[state.current_hovered_obj];
+    Face *f = &o->faces[state.current_hovered_face];
+
+    if (f->p[3] != INVALID_POINT) {
+        Vec3 p0 = point_to_vec3(state.current_hovered_obj, f->p[0]);
+        Vec3 p1 = point_to_vec3(state.current_hovered_obj, f->p[1]);
+        Vec3 p2 = point_to_vec3(state.current_hovered_obj, f->p[2]);
+        Vec3 p3 = point_to_vec3(state.current_hovered_obj, f->p[3]);
+        Vec3 center = vec3_scale(vec3_add(p2, p0), 0.5);
+        float size = sinf(ctx.frame_number / 10) * 0.05f + 0.1f;
+        Vec3 c0 = vec3_add(p0, vec3_scale(vec3_sub(p0, center), size));
+        Vec3 c1 = vec3_add(p1, vec3_scale(vec3_sub(p1, center), size));
+        Vec3 c2 = vec3_add(p2, vec3_scale(vec3_sub(p2, center), size));
+        Vec3 c3 = vec3_add(p3, vec3_scale(vec3_sub(p3, center), size));
+        draw_line_3d(c0, c1, 1, (Color){255,255,255,255});
+        draw_line_3d(c1, c2, 1, (Color){255,255,255,255});
+        draw_line_3d(c2, c3, 1, (Color){255,255,255,255});
+        draw_line_3d(c3, c0, 1, (Color){255,255,255,255});
+    } else {
+        Vec3 p0 = point_to_vec3(state.current_hovered_obj, f->p[0]);
+        Vec3 p1 = point_to_vec3(state.current_hovered_obj, f->p[1]);
+        Vec3 p2 = point_to_vec3(state.current_hovered_obj, f->p[2]);
+        Vec3 center = vec3_scale(vec3_add(p0, vec3_add(p1, p2)), 0.33f);
+        float size = sinf(ctx.frame_number / 10) * 0.05f + 0.1f;
+        Vec3 c0 = vec3_add(p0, vec3_scale(vec3_sub(p0, center), size));
+        Vec3 c1 = vec3_add(p1, vec3_scale(vec3_sub(p1, center), size));
+        Vec3 c2 = vec3_add(p2, vec3_scale(vec3_sub(p2, center), size));
+        draw_line_3d(c0, c1, 1, (Color){255,255,255,255});
+        draw_line_3d(c1, c2, 1, (Color){255,255,255,255});
+        draw_line_3d(c2, c0, 1, (Color){255,255,255,255});
+    }
+}
+
+
+static void display_texture_selection(void) {
+    String list = file_read("/data/assets/", ":images");
+    if (!list.data)
+        return;
+
+    draw_rectangle((Rect){0, 480 - 50, 640, 480}, (Color){0,0,0,126});
+
+    char *selected = NULL;
+    char *saveptr = NULL;
+    int count = 0;
+    char const *part = SDL_strtokr(list.data, "\n", &saveptr);
+    do {
+        Rect box = (Rect){(float)count * 50, 480 - 48, 48, 48};
+        draw_sprite(part,
+                    box,
+                    (Rect){0,0,64,64},
+                    (Color){255,255,255,255},
+                    0, false, false, true);
+        count++;
+
+        if (state.current_texture && SDL_strcmp(part, state.current_texture) == 0)
+            draw_box(box, 1, (Color){255,255,255,255});
+
+        if (rect_intersects(box, (Rect){ctx.mouse_position.x, ctx.mouse_position.y, 1, 1}))
+            selected = SDL_strdup(part);
+
+    } while ((part = SDL_strtokr(NULL, "\n", &saveptr)));
+
+    if (selected) {
+        draw_text(selected, (Vec2){0, 480 - 48 - 24}, 24, (Color){255,255,255,255}, NULL);
+        if (input_action_just_pressed("select")) {
+            if (state.current_texture) SDL_free(state.current_texture);
+            state.current_texture = selected;
+        } else
+            SDL_free(selected);
+    }
+}
+
+
+static void process_camera_inputs(void) {
+    if (input_action_just_pressed("toggle_display_mode")) {
+        audio_play("/data/click.wav", NULL, false, 0.7f, 0.0f);
+        state.solid_display_mode = !state.solid_display_mode;
+        if (state.current_texture) {
+            SDL_free(state.current_texture);
+            state.current_texture = NULL;
+        }
+    }
+
+    if (input_action_just_pressed("toggle_projection")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = !state.camera_is_orthographic;
+    }
+
+    if (input_action_just_pressed("toggle_x_axis")) {
+        state.axis_mask[0] = 0; state.axis_mask[1] = 1; state.axis_mask[2] = 1;
+    }
+
+    if (input_action_just_pressed("toggle_y_axis")) {
+        state.axis_mask[0] = 1; state.axis_mask[1] = 0; state.axis_mask[2] = 1;
+    }
+
+    if (input_action_just_pressed("toggle_z_axis")) {
+        state.axis_mask[0] = 1; state.axis_mask[1] = 1; state.axis_mask[2] = 0;
+    }
+
+    /* TODO: determine bounding box for this? */
+    /* TODO: no idea whether it's all correct in terms of directions. */
+    if (input_action_just_pressed("camera_front")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){0,0,-1};
+        state.camera_position = vec3_add(state.active_center, (Vec3){0,0,2});
+    }
+
+    if (input_action_just_pressed("camera_back")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){0,0,1};
+        state.camera_position = vec3_add(state.active_center, (Vec3){0,0,-2});
+    }
+
+    if (input_action_just_pressed("camera_left")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){1,0,0};
+        state.camera_position = vec3_add(state.active_center, (Vec3){-2,0,0});
+    }
+
+    if (input_action_just_pressed("camera_right")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){-1,0,0};
+        state.camera_position = vec3_add(state.active_center, (Vec3){2,0,0});
+    }
+
+    /* TODO: broken */
+    if (input_action_just_pressed("camera_above")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){0,-1,0};
+        state.camera_position = vec3_add(state.active_center, (Vec3){0,2,0});
+    }
+
+    /* TODO: broken */
+    if (input_action_just_pressed("camera_below")) {
+        audio_play("/data/pop.wav", NULL, false, 0.8f, 0.0f);
+        state.camera_is_orthographic = true;
+        state.camera_direction = (Vec3){0,1,0};
+        state.camera_position = vec3_add(state.active_center, (Vec3){0,-2,0});
+    }
+}
+
+
+void game_tick(void) {
+    if (!init) {
+        /* default state */
+        new_cube((Point){0,0,0}, (Point){POINTS_PER_METER,POINTS_PER_METER,POINTS_PER_METER});
+        state.camera_position = (Vec3){2,1,2};
+        state.camera_direction = vec3_norm(((Vec3){-2,-1,-2}));
+        state.camera_zoom = 0.5f;
+        state.grid_snap_granularity = 16;
+        state.axis_mask[1] = 1; state.axis_mask[2] = 1;
+        init = true;
+    }
+
+    state.current_hovered_face = INVALID_FACE;
+    state.current_hovered_obj = INVALID_OBJECT;
+
+    input_action("toggle_display_mode", "Q");
+    input_action("toggle_projection", "TAB");
+
+    input_action("toggle_x_axis",   "Z");
+    input_action("toggle_y_axis",   "X");
+    input_action("toggle_z_axis",   "C");
+
+    input_action("select",          "LCLICK");
+    input_action("rotate",          "R");
+    input_action("undo",            "F");
+
+    input_action("camera_front",    "KP0");
+    input_action("camera_back",     "KP1");
+    input_action("camera_left",     "KP2");
+    input_action("camera_right",    "KP3");
+    input_action("camera_above",    "KP4");
+    input_action("camera_below",    "KP5");
+
+    process_camera_inputs();
+    process_camera_movement();
+    process_operations();
+
+    /* helpres */
+    draw_axes();
+    draw_hovered_face_border();
+
+    for (uint8_t obj = 0; obj < state.objects_sz; ++obj)
+        render_object(obj);
+
+    if (state.solid_display_mode)
+        display_texture_selection();
+
+    draw_text("twndel\x03", (Vec2){0, 2}, 32, (Color){255,255,255,200}, NULL);
+    draw_camera(
+        state.camera_position,
+        state.camera_direction,
+        (Vec3){0, 1, 0},
+        state.camera_is_orthographic ? 0 : CAMERA_FOV,
+        state.camera_zoom,
+        100
+    );
+}
+
+
+void game_end(void) {
+    for (uint8_t obj = 0; obj < state.objects_sz; ++obj) {
+        Object *o = &state.objects[obj];
+        for (uint8_t t = 0; t < o->textures_sz; ++t)
+            SDL_free(o->textures[t]);
+        SDL_free(o->name);
+    }
+    if (state.current_texture) {
+        SDL_free(state.current_texture);
+        state.current_texture = NULL;
+    }
+}

apps/twnlua/.gitignore

@@ -1 +1,2 @@
 luabind.c
+data/scripts/twnapi.lua

apps/twnlua/CMakeLists.txt

@@ -1,42 +1,36 @@
-cmake_minimum_required(VERSION 3.21)
+cmake_minimum_required(VERSION 3.30)
-cmake_policy(SET CMP0171 NEW)
 project(twnlua LANGUAGES C)
 
+find_package(Python3 COMPONENTS Interpreter)
+
 if(NOT CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-add_subdirectory($ENV{TWNROOT} $ENV{TWNROOT}/build)
+add_subdirectory($ENV{TWNROOT} ${CMAKE_BINARY_DIR}/twn)
-
-set(FLAGS
-        $<$<NOT:$<BOOL:${TWN_FEATURE_DYNLIB_GAME}>>:--no-dynlib-game>
-)
 
 add_custom_command(
-   OUTPUT ${CMAKE_CURRENT_SOURCE_DIR}/luabind.c
+   OUTPUT ${CMAKE_CURRENT_SOURCE_DIR}/game.c
-   COMMAND ${PYTHON3} ${CMAKE_CURRENT_SOURCE_DIR}/bindgen.py $ENV{TWNROOT}/share/twn_api.json ${FLAGS} > ${CMAKE_CURRENT_SOURCE_DIR}/luabind.c
+   COMMAND ${Python3_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/bindgen.py $ENV{TWNROOT}/share/twn_api.json ${FLAGS} > ${CMAKE_CURRENT_SOURCE_DIR}/luabind.c
    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/bindgen.py $ENV{TWNROOT}/share/twn_api.json
-   CODEGEN
 )
 
 add_custom_command(
-   OUTPUT ${CMAKE_SOURCE_DIR}/data/scripts/twnapi.lua
+   OUTPUT ${TWN_OUT_DIR}/data/scripts/twnapi.lua
-   COMMAND ${PYTHON3} ${CMAKE_CURRENT_SOURCE_DIR}/docgen.py $ENV{TWNROOT}/share/twn_api.json > ${CMAKE_SOURCE_DIR}/data/scripts/twnapi.lua
+   COMMAND ${Python3_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/docgen.py $ENV{TWNROOT}/share/twn_api.json > ${TWN_OUT_DIR}/data/scripts/twnapi.lua
    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/docgen.py $ENV{TWNROOT}/share/twn_api.json
 )
 
 add_custom_target(
     twnlua_docgen ALL
-    DEPENDS ${CMAKE_SOURCE_DIR}/data/scripts/twnapi.lua
+    DEPENDS ${TWN_OUT_DIR}/data/scripts/twnapi.lua
 )
 
-add_compile_definitions(LUA_32BITS)
+add_compile_definitions(LUA_32BITS=1)
 
 set(SOURCE_FILES
         game.c
-        state.h
         minilua.c
-        ${CMAKE_CURRENT_SOURCE_DIR}/luabind.c
 )
 
-use_townengine(${CMAKE_PROJECT_NAME} "${SOURCE_FILES}" ${CMAKE_SOURCE_DIR})
+use_townengine("${SOURCE_FILES}" ${TWN_OUT_DIR})

apps/twnlua/bindgen.py

@@ -36,7 +36,7 @@ def to_table(typedesc, variable, indent = 0):
     binding = ' ' * indent + "lua_createtable(L, 0, %i);\n" % len(typedesc["fields"])
     for field in typedesc["fields"]:
         if field["type"] == "float" or field["type"] == "uint8_t":
-            binding += ' ' * indent + "lua_pushnumber(L, (double)(%s));\n" % (variable + ".%s" % field["name"])
+            binding += ' ' * indent + "lua_pushnumber(L, (float)(%s));\n" % (variable + ".%s" % field["name"])
         elif field["type"] == "bool":
             binding += ' ' * indent + "lua_pushboolean(L, (%s));\n" % (variable + ".%s" % field["name"])
         elif field["type"] in api["types"]:
@@ -64,10 +64,7 @@ def from_table(typedesc, variable, indent = 0):
 
 
 print('#include "twn_game_api.h"\n')
-if not "--no-dynlib-game" in sys.argv:
+print('/* assumed to be included from game.c, where minilua.h is already present */\n')
-    print('#define STB_DS_IMPLEMENTATION')
-print('#include <stb_ds.h>')
-print('#include "minilua.h"\n')
 
 bindings, used_converters = [], {}
 for procedure, procedure_desc in api["procedures"].items():
@@ -112,11 +109,13 @@ for procedure, procedure_desc in api["procedures"].items():
         if procedure_desc["return"] == "bool":
             binding += "    lua_pushboolean(L, (int)(%s(%s)));\n" % (procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
         elif procedure_desc["return"] == "float":
-            binding += "    lua_pushnumber(L, (double)(%s(%s)));\n" % (procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
+            binding += "    lua_pushnumber(L, (float)(%s(%s)));\n" % (procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
         elif procedure_desc["return"] == "char *":
             binding += "    lua_pushstring(L, %s(%s));\n" % (procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
+        elif procedure_desc["return"] == "String":
+            binding += "    String result = %s(%s);\n" % (procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
+            binding += "    lua_pushlstring(L, result.data, (int)result.length);\n"
         elif type(procedure_desc["return"]) is dict or procedure_desc["return"] in api["types"]:
-            # TODO: handle enums
             type_desc = procedure_desc["return"] if type(procedure_desc["return"]) is dict else api["types"][procedure_desc["return"]]
             binding += "    %s result = %s(%s);\n" % (type_desc["c_type"], procedure, ", ".join(param["name"] for param in procedure_desc["params"]))
             binding += to_table(type_desc, "result", 4)
@@ -150,35 +149,17 @@ for typename, typedesc in used_converters.items():
                 raise BaseException("Unhandled converter field type '%s'" % (field["type"]))
         converter += "    lua_pop(L, %i);\n" % len(typedesc["fields"]);
 
-    # TODO: wild idea: use compile time built hash table
-    elif "enums" in typedesc:
-        storages += ["struct %sHashItem { char *key; %s value; };\nstatic struct %sHashItem *%s_map = NULL;\n" % (typename, typename, typename, typename.lower())]
-
-        # TODO: use arena
-        for enum in typedesc["enums"]:
-            initializer = "    shput(%s_map, \"%s\", %s);" % (typename.lower(), enum, typedesc["enums"][enum])
-            initializers += [initializer]
-
-        deinitializers += ["    shfree(%s_map);" % typename.lower()]
-
-        converter += "    char const *value = lua_tostring(L, -1);\n";
-        converter += "        %s = shget(%s_map, value);\n" % (typename.lower(), typename.lower())
-        converter += "    lua_pop(L, 1);\n";
-
     converter += "    return %s;\n}\n" % (typename.lower())
     converters += [converter]
 
 
 print('\n'.join(storages))
-print("extern void bindgen_init(void);\n")
-print("void bindgen_init(void) {\n" + '\n'.join(initializers) + "\n}\n")
 print('\n'.join(converters))
 print('\n'.join(bindings))
 
 
 loader = "extern void bindgen_load_%s(lua_State *L);\n" % api["name"]
 loader += "void bindgen_load_%s(lua_State *L) {\n" % api["name"]
-loader += "    bindgen_init();\n"
 for procedure, procedure_desc in api["procedures"].items():
     loader += "    lua_pushcfunction(L, binding_%s);\n" % procedure
     loader += "    lua_setglobal(L, \"%s\");\n" % procedure

apps/twnlua/data/packs/data.toml

@@ -1,3 +1,3 @@
 [[deps]]
-source = "../../common-data" # where does it come from, might be an url
+source = "../../data" # where does it come from, might be an url
-name = "common-data"         # should be globally unique
+name = "common-data"  # should be globally unique

apps/twnlua/data/scripts/game.lua

@@ -4,16 +4,39 @@ offset = { x = 0, y = 0 }
 angle = 0
 
 function game_tick()
+    if ctx.udata == nil then
+        ctx.udata = {
+            frame_count = 0,
+            nest = {
+                frame_count = 0,
+            },
+            arr = { [0] = 0 },
+        }
+    end
+
+    draw_text {
+        string = tostring(ctx.udata.frame_count),
+        position = { x = 0, y = 0 },
+        font = "/fonts/kenney-pixel.ttf",
+    }
+
+    draw_text {
+        string = tostring(ctx.udata.nest.frame_count),
+        position = { x = 0, y = 14 },
+        font = "/fonts/kenney-pixel.ttf",
+    }
+
+    draw_text {
+        string = tostring(ctx.udata.arr[0]),
+        position = { x = 0, y = 28 },
+        font = "/fonts/kenney-pixel.ttf",
+    }
+
     input_action {
         name = "press",
         control = "A"
     }
 
-    draw_rectangle {
-        rect = { x = 0, y = 0, w = 640, h = 360 },
-        color = { r = 127, g = 0, b = 127, a = 255 },
-    }
-
     draw_sprite {
         texture = "/assets/title.png",
         rect = {
@@ -32,6 +55,10 @@ function game_tick()
         }
     end
 
+    ctx.udata.frame_count = ctx.udata.frame_count + 1
+    ctx.udata.nest.frame_count = ctx.udata.nest.frame_count + 1
+    ctx.udata.arr[0] = ctx.udata.arr[0] + 1
+
     offset.x = ORIGIN.x + (math.cos(angle) * RADIUS)
     offset.y = ORIGIN.y + (math.sin(angle) * RADIUS)
     angle = angle + 0.1

apps/twnlua/data/twn.toml

@@ -6,5 +6,6 @@ dev_id = "somebody"
 
 [game]
 resolution = [ 640, 360 ]
+background_color = [ 127, 0, 127, 255 ]
 
 [engine]

apps/twnlua/docgen.py

@@ -7,16 +7,16 @@ with open(sys.argv[1], 'r') if sys.argv[1] != "-" else sys.stdin as f:
 
 api = json.loads(api_source)
 
-def to_lua_type_annot(typename):
+def to_lua_type_annot(typedesc):
-    basetype = typename.rsplit(' *', 1)[0]
+    if type(typedesc) is dict:
-    if typename == "char *":
+        return r'{ %s }' % ','.join('%s: %s' % (f["name"], to_lua_type_annot(f["type"])) for f in typedesc["fields"])
+    basetype = typedesc.rsplit(' *', 1)[0]
+    if typedesc == "char *":
         return "string"
     elif basetype == "float":
         return "number"
     elif basetype == "bool":
         return "boolean"
-    elif basetype == "Control":
-        return "Control"
     elif basetype == "Vec2":
         return r"{ x: number, y: number }"
     elif basetype == "Vec3":
@@ -27,9 +27,12 @@ def to_lua_type_annot(typename):
         return r"{ x: number, y: number, w: number, h: number }"
     else:
         return "unknown"
-        # raise BaseException("Unhandled type for annotation: %s" % typename)
+        # raise BaseException("Unhandled type for annotation: %s" % typedesc)
 
-type_annotations, enum_annotations = {}, {}
+print("---@meta twn")
+print("---@diagnostic disable")
+
+type_annotations = {}
 type_annotations["ctx"] = r"{ %s, udata: table }" % \
     ', '.join("%s: %s" % (f["name"], to_lua_type_annot(f["type"])) for f in api["types"]["Context"]["fields"])
 
@@ -37,17 +40,16 @@ for annot in type_annotations:
     print("---@type " + type_annotations[annot])
     print(r"%s = nil" % annot)
 
-enum_annotations["Control"] = \
-    '|'.join('\'"%s"\'' % e for e in api["types"]["Control"]["enums"])
-
-for annot in enum_annotations:
-    print("---@alias %s %s" % (annot, enum_annotations[annot]))
-
 procedure_annotations = {}
 for procedure, procedure_desc in api["procedures"].items():
-    procedure_annotations[procedure] = r"{ %s }" % \
+    procedure_annotations[procedure] = {}
+    procedure_annotations[procedure]["params"] = r"{ %s }" % \
         ', '.join("%s: %s" % (p["name"], to_lua_type_annot(p["type"]) + '?' * ("default" in p)) for p in procedure_desc["params"])
+    if "return" in procedure_desc:
+        procedure_annotations[procedure]["return"] = to_lua_type_annot(procedure_desc["return"])
 
 for annot in procedure_annotations:
-    print("---@param args " + procedure_annotations[annot])
+    print("---@param args " + procedure_annotations[annot]["params"])
+    if "return" in procedure_annotations[annot]:
+        print("---@return " + procedure_annotations[annot]["return"])
     print("function %s(args) end" % annot)

apps/twnlua/game.c

@@ -1,9 +1,15 @@
 #include "twn_game_api.h"
-#include "state.h"
 
+/* TODO: actually move it back it its own file, it doesn't give any compilation benefits */
 #include "minilua.h"
+
+#include "state.h"
+#include "luabind.c"
+
 #include <SDL2/SDL.h>
 
+#define UDATA_NESTING_LIMIT 128
+
 
 /* generated by bindgen.py */
 void bindgen_load_twn(lua_State *L);
@@ -14,30 +20,48 @@ void bindgen_upload_context(lua_State *L);
 
 /* require will go through physicsfs exclusively so that scripts can be in the data dir */
 /* TODO: allow for bytecode files */
+/* TODO: support .lua suffixes files? */
 static int physfs_loader(lua_State *L) {
     const char *name = luaL_checkstring(L, 1);
-    char *final_path = NULL;
-    SDL_asprintf(&final_path, "/scripts/%s.lua", name);
 
-    if (!file_exists(final_path)) {
+    static const char *name_breaker = NULL;
+    if (name_breaker && SDL_strcmp(name, name_breaker) == 0) {
+        log_string(name_breaker, "Recursive load on itself from lua module");
+        return 0;
+    } name_breaker = name;
+
+    /* replace dots with path slashes */
+    char *path_copy = SDL_strdup(name);
+    char *ch = NULL;
+    while ((ch = SDL_strchr(path_copy, '.')))
+        *ch = '/';
+
+    char *final_path = NULL;
+    SDL_asprintf(&final_path, "/scripts/%s.lua", path_copy);
+    SDL_free(path_copy);
+
+    if (SDL_strcmp(file_read(final_path, ":exists").data, "yes") == 0) {
         char *error_message = NULL;
         SDL_asprintf(&error_message, "could not find module %s in filesystem", name);
         lua_pushstring(L, error_message);
-        free(error_message);
+        SDL_free(error_message);
 
-        free(final_path);
+        SDL_free(final_path);
         return 1;
     }
 
-    unsigned char *buf = NULL;
+    char *final_path_binary = NULL;
-    int64_t buf_size = file_to_bytes(final_path, &buf);
+    SDL_asprintf(&final_path_binary, "%s%s", final_path, ":binary");
-    free(final_path);
+
+    String file = file_read(final_path, ":binary");
+    SDL_free(final_path);
 
     /* TODO: use reader interface for streaming instead */
-    luaL_loadbuffer(L, (char *)buf, buf_size, name);
+    int const result = luaL_loadbuffer(L, file.data, (size_t)file.length, name);
-    free(buf);
+    if (result != LUA_OK)
+        log_string(lua_tostring(L, -1), NULL);
 
-    return 1;
+    return result == LUA_OK;
 }
 
 
@@ -84,21 +108,76 @@ static void *custom_alloc(void *ud, void *ptr, size_t osize, size_t nsize) {
 }
 
 
+static void exchange_lua_states(lua_State *from, lua_State *to, int level, int index) {
+    if (level >= UDATA_NESTING_LIMIT) {
+        log_string("ctx.udata nesting limit is reached", NULL);
+        return;
+    }
+
+    /* TODO: use arrays for optimized paths */
+    /* TODO: preallocate table records */
+    switch (lua_type(from, index)) {
+    case LUA_TTABLE:
+        lua_newtable(to);
+        lua_pushnil(from); /* first key */
+        while (lua_next(from, index - 1) != 0) {
+            /* 'key' at index -2 and 'value' at index -1 */
+            exchange_lua_states(from, to, level + 1, -2);
+            exchange_lua_states(from, to, level + 1, -1);
+            lua_settable(to, index - 2);
+            /* removes 'value'; keeps 'key' for next iteration */
+            lua_pop(from, 1);
+        }
+        break;
+    case LUA_TNUMBER:
+        lua_pushnumber(to, lua_tonumber(from, index));
+        break;
+    case LUA_TBOOLEAN:
+        lua_pushboolean(to, lua_toboolean(from, index));
+        break;
+    case LUA_TSTRING:
+        lua_pushstring(to, lua_tostring(from, index));
+        break;
+    case LUA_TNIL:
+        lua_pushnil(to);
+        break;
+    default:
+        /* TODO: provide a path and type of it for better diagnostic */
+        log_string("Unserializable udata found and is ignored", NULL);
+        break;
+    }
+}
+
+
 void game_tick(void) {
     if (ctx.initialization_needed) {
         if (!ctx.udata)
-            ctx.udata = ccalloc(1, sizeof (State));
+            ctx.udata = SDL_calloc(1, sizeof (State));
 
         State *state = ctx.udata;
 
         /* let's init lua */
-        /* state existed already */
+        lua_State *new_state = lua_newstate(custom_alloc, NULL);
+        lua_setallocf(new_state, custom_alloc, NULL);
+
+        /* state existed already, copy its udata over */
         if (state->L != NULL) {
+            lua_getglobal(state->L, "ctx");
+            lua_getfield(state->L, -1, "udata");
+            SDL_assert(!lua_isnoneornil(state->L, -1));
+            SDL_assert(!lua_isnoneornil(state->L, -2));
+            if (!lua_isnoneornil(state->L, -1)) {
+                lua_newtable(new_state);
+                exchange_lua_states(state->L, new_state, 0, -1);
+                lua_setfield(new_state, -2, "udata");
+                lua_setglobal(new_state, "ctx");
+            }
+
+            /* bye :) */
             lua_close(state->L);
         }
-        state->L = luaL_newstate();
 
-        lua_setallocf(state->L, custom_alloc, NULL);
+        state->L = new_state;
 
         /* fakey version of luaL_openlibs() that excludes file i/o and os stuff */
         {
@@ -136,24 +215,21 @@ void game_tick(void) {
         bindgen_load_twn(state->L);
 
         /* now finally get to running the code */
-        unsigned char *game_buf = NULL;
+        String file = file_read("/scripts/game.lua", ":binary");
-        size_t game_buf_size = file_to_bytes("/scripts/game.lua", &game_buf);
         /* TODO: use reader interface for streaming instead */
-        if (luaL_loadbuffer(state->L, (char *)game_buf, game_buf_size, "game.lua") == LUA_OK) {
+        if (luaL_loadbuffer(state->L, file.data, (size_t)file.length, "game.lua") == LUA_OK) {
             if (lua_pcall(state->L, 0, 0, 0) != LUA_OK) {
-                log_critical("%s", lua_tostring(state->L, -1));
+                log_string(luaL_tolstring(state->L, -1, NULL), "Error executing /scripts/game.lua entry");
                 lua_pop(state->L, 1);
             } else
                 state->loaded_successfully = true;
         } else {
             /* got some sort of error, it should be pushed on top of the stack */
             SDL_assert(lua_isstring(state->L, -1));
-            log_critical("Error loading /scripts/game.lua entry: %s", luaL_tolstring(state->L, -1, NULL));
+            log_string(luaL_tolstring(state->L, -1, NULL), "Error loading /scripts/game.lua entry");
             lua_pop(state->L, 1);
         }
 
-        free(game_buf);
-
         /* from this point we have access to everything defined in lua */
     }
 
@@ -171,7 +247,7 @@ void game_tick(void) {
 
         lua_getglobal(state->L, "game_tick");
         if (lua_pcall(state->L, 0, 0, 0) != LUA_OK) {
-            log_critical("%s", lua_tostring(state->L, -1));
+            log_string(luaL_tolstring(state->L, -1, NULL), "Error executing game_tick()");
             lua_pop(state->L, 1);
         }
 
@@ -185,5 +261,5 @@ void game_end(void) {
     State *state = ctx.udata;
     bindgen_unload_twn(state->L);
     lua_close(state->L);
-    free(state);
+    SDL_free(state);
 }

apps/twnlua/minilua.h

@@ -210,8 +210,9 @@ extern "C" {
 /*
 @@ LUA_32BITS enables Lua with 32-bit integers and 32-bit floats.
 */
+#if !defined(LUA_32BITS)
 #define LUA_32BITS	0
-
+#endif
 
 /*
 @@ LUA_C89_NUMBERS ensures that Lua uses the largest types available for
@@ -382,7 +383,8 @@ extern "C" {
 
 #else				/* }{ */
 
-#define LUA_API		extern
+/* TWN: Don't export anything, there's no need. */
+#define LUA_API		LUAI_FUNC
 
 #endif				/* } */
 
@@ -28631,696 +28633,6 @@ LUALIB_API void luaL_openlibs (lua_State *L) {
 #ifdef __cplusplus
 }
 #endif
-#ifdef LUA_MAKE_LUA
-/*
-** $Id: lua.c $
-** Lua stand-alone interpreter
-** See Copyright Notice in lua.h
-*/
-
-#define lua_c
-
-/*#include "lprefix.h"*/
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <signal.h>
-
-/*#include "lua.h"*/
-
-/*#include "lauxlib.h"*/
-/*#include "lualib.h"*/
-
-
-#if !defined(LUA_PROGNAME)
-#define LUA_PROGNAME		"lua"
-#endif
-
-#if !defined(LUA_INIT_VAR)
-#define LUA_INIT_VAR		"LUA_INIT"
-#endif
-
-#define LUA_INITVARVERSION	LUA_INIT_VAR LUA_VERSUFFIX
-
-
-static lua_State *globalL = NULL;
-
-static const char *progname = LUA_PROGNAME;
-
-
-#if defined(LUA_USE_POSIX)   /* { */
-
-/*
-** Use 'sigaction' when available.
-*/
-static void setsignal (int sig, void (*handler)(int)) {
-  struct sigaction sa;
-  sa.sa_handler = handler;
-  sa.sa_flags = 0;
-  sigemptyset(&sa.sa_mask);  /* do not mask any signal */
-  sigaction(sig, &sa, NULL);
-}
-
-#else           /* }{ */
-
-#define setsignal            signal
-
-#endif                               /* } */
-
-
-/*
-** Hook set by signal function to stop the interpreter.
-*/
-static void lstop (lua_State *L, lua_Debug *ar) {
-  (void)ar;  /* unused arg. */
-  lua_sethook(L, NULL, 0, 0);  /* reset hook */
-  luaL_error(L, "interrupted!");
-}
-
-
-/*
-** Function to be called at a C signal. Because a C signal cannot
-** just change a Lua state (as there is no proper synchronization),
-** this function only sets a hook that, when called, will stop the
-** interpreter.
-*/
-static void laction (int i) {
-  int flag = LUA_MASKCALL | LUA_MASKRET | LUA_MASKLINE | LUA_MASKCOUNT;
-  setsignal(i, SIG_DFL); /* if another SIGINT happens, terminate process */
-  lua_sethook(globalL, lstop, flag, 1);
-}
-
-
-static void print_usage (const char *badoption) {
-  lua_writestringerror("%s: ", progname);
-  if (badoption[1] == 'e' || badoption[1] == 'l')
-    lua_writestringerror("'%s' needs argument\n", badoption);
-  else
-    lua_writestringerror("unrecognized option '%s'\n", badoption);
-  lua_writestringerror(
-  "usage: %s [options] [script [args]]\n"
-  "Available options are:\n"
-  "  -e stat   execute string 'stat'\n"
-  "  -i        enter interactive mode after executing 'script'\n"
-  "  -l mod    require library 'mod' into global 'mod'\n"
-  "  -l g=mod  require library 'mod' into global 'g'\n"
-  "  -v        show version information\n"
-  "  -E        ignore environment variables\n"
-  "  -W        turn warnings on\n"
-  "  --        stop handling options\n"
-  "  -         stop handling options and execute stdin\n"
-  ,
-  progname);
-}
-
-
-/*
-** Prints an error message, adding the program name in front of it
-** (if present)
-*/
-static void l_message (const char *pname, const char *msg) {
-  if (pname) lua_writestringerror("%s: ", pname);
-  lua_writestringerror("%s\n", msg);
-}
-
-
-/*
-** Check whether 'status' is not OK and, if so, prints the error
-** message on the top of the stack.
-*/
-static int report (lua_State *L, int status) {
-  if (status != LUA_OK) {
-    const char *msg = lua_tostring(L, -1);
-    if (msg == NULL)
-      msg = "(error message not a string)";
-    l_message(progname, msg);
-    lua_pop(L, 1);  /* remove message */
-  }
-  return status;
-}
-
-
-/*
-** Message handler used to run all chunks
-*/
-static int msghandler (lua_State *L) {
-  const char *msg = lua_tostring(L, 1);
-  if (msg == NULL) {  /* is error object not a string? */
-    if (luaL_callmeta(L, 1, "__tostring") &&  /* does it have a metamethod */
-        lua_type(L, -1) == LUA_TSTRING)  /* that produces a string? */
-      return 1;  /* that is the message */
-    else
-      msg = lua_pushfstring(L, "(error object is a %s value)",
-                               luaL_typename(L, 1));
-  }
-  luaL_traceback(L, L, msg, 1);  /* append a standard traceback */
-  return 1;  /* return the traceback */
-}
-
-
-/*
-** Interface to 'lua_pcall', which sets appropriate message function
-** and C-signal handler. Used to run all chunks.
-*/
-static int docall (lua_State *L, int narg, int nres) {
-  int status;
-  int base = lua_gettop(L) - narg;  /* function index */
-  lua_pushcfunction(L, msghandler);  /* push message handler */
-  lua_insert(L, base);  /* put it under function and args */
-  globalL = L;  /* to be available to 'laction' */
-  setsignal(SIGINT, laction);  /* set C-signal handler */
-  status = lua_pcall(L, narg, nres, base);
-  setsignal(SIGINT, SIG_DFL); /* reset C-signal handler */
-  lua_remove(L, base);  /* remove message handler from the stack */
-  return status;
-}
-
-
-static void print_version (void) {
-  lua_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
-  lua_writeline();
-}
-
-
-/*
-** Create the 'arg' table, which stores all arguments from the
-** command line ('argv'). It should be aligned so that, at index 0,
-** it has 'argv[script]', which is the script name. The arguments
-** to the script (everything after 'script') go to positive indices;
-** other arguments (before the script name) go to negative indices.
-** If there is no script name, assume interpreter's name as base.
-** (If there is no interpreter's name either, 'script' is -1, so
-** table sizes are zero.)
-*/
-static void createargtable (lua_State *L, char **argv, int argc, int script) {
-  int i, narg;
-  narg = argc - (script + 1);  /* number of positive indices */
-  lua_createtable(L, narg, script + 1);
-  for (i = 0; i < argc; i++) {
-    lua_pushstring(L, argv[i]);
-    lua_rawseti(L, -2, i - script);
-  }
-  lua_setglobal(L, "arg");
-}
-
-
-static int dochunk (lua_State *L, int status) {
-  if (status == LUA_OK) status = docall(L, 0, 0);
-  return report(L, status);
-}
-
-
-static int dofile (lua_State *L, const char *name) {
-  return dochunk(L, luaL_loadfile(L, name));
-}
-
-
-static int dostring (lua_State *L, const char *s, const char *name) {
-  return dochunk(L, luaL_loadbuffer(L, s, strlen(s), name));
-}
-
-
-/*
-** Receives 'globname[=modname]' and runs 'globname = require(modname)'.
-** If there is no explicit modname and globname contains a '-', cut
-** the suffix after '-' (the "version") to make the global name.
-*/
-static int dolibrary (lua_State *L, char *globname) {
-  int status;
-  char *suffix = NULL;
-  char *modname = strchr(globname, '=');
-  if (modname == NULL) {  /* no explicit name? */
-    modname = globname;  /* module name is equal to global name */
-    suffix = strchr(modname, *LUA_IGMARK);  /* look for a suffix mark */
-  }
-  else {
-    *modname = '\0';  /* global name ends here */
-    modname++;  /* module name starts after the '=' */
-  }
-  lua_getglobal(L, "require");
-  lua_pushstring(L, modname);
-  status = docall(L, 1, 1);  /* call 'require(modname)' */
-  if (status == LUA_OK) {
-    if (suffix != NULL)  /* is there a suffix mark? */
-      *suffix = '\0';  /* remove suffix from global name */
-    lua_setglobal(L, globname);  /* globname = require(modname) */
-  }
-  return report(L, status);
-}
-
-
-/*
-** Push on the stack the contents of table 'arg' from 1 to #arg
-*/
-static int pushargs (lua_State *L) {
-  int i, n;
-  if (lua_getglobal(L, "arg") != LUA_TTABLE)
-    luaL_error(L, "'arg' is not a table");
-  n = (int)luaL_len(L, -1);
-  luaL_checkstack(L, n + 3, "too many arguments to script");
-  for (i = 1; i <= n; i++)
-    lua_rawgeti(L, -i, i);
-  lua_remove(L, -i);  /* remove table from the stack */
-  return n;
-}
-
-
-static int handle_script (lua_State *L, char **argv) {
-  int status;
-  const char *fname = argv[0];
-  if (strcmp(fname, "-") == 0 && strcmp(argv[-1], "--") != 0)
-    fname = NULL;  /* stdin */
-  status = luaL_loadfile(L, fname);
-  if (status == LUA_OK) {
-    int n = pushargs(L);  /* push arguments to script */
-    status = docall(L, n, LUA_MULTRET);
-  }
-  return report(L, status);
-}
-
-
-/* bits of various argument indicators in 'args' */
-#define has_error	1	/* bad option */
-#define has_i		2	/* -i */
-#define has_v		4	/* -v */
-#define has_e		8	/* -e */
-#define has_E		16	/* -E */
-
-
-/*
-** Traverses all arguments from 'argv', returning a mask with those
-** needed before running any Lua code or an error code if it finds any
-** invalid argument. In case of error, 'first' is the index of the bad
-** argument.  Otherwise, 'first' is -1 if there is no program name,
-** 0 if there is no script name, or the index of the script name.
-*/
-static int collectargs (char **argv, int *first) {
-  int args = 0;
-  int i;
-  if (argv[0] != NULL) {  /* is there a program name? */
-    if (argv[0][0])  /* not empty? */
-      progname = argv[0];  /* save it */
-  }
-  else {  /* no program name */
-    *first = -1;
-    return 0;
-  }
-  for (i = 1; argv[i] != NULL; i++) {  /* handle arguments */
-    *first = i;
-    if (argv[i][0] != '-')  /* not an option? */
-        return args;  /* stop handling options */
-    switch (argv[i][1]) {  /* else check option */
-      case '-':  /* '--' */
-        if (argv[i][2] != '\0')  /* extra characters after '--'? */
-          return has_error;  /* invalid option */
-        *first = i + 1;
-        return args;
-      case '\0':  /* '-' */
-        return args;  /* script "name" is '-' */
-      case 'E':
-        if (argv[i][2] != '\0')  /* extra characters? */
-          return has_error;  /* invalid option */
-        args |= has_E;
-        break;
-      case 'W':
-        if (argv[i][2] != '\0')  /* extra characters? */
-          return has_error;  /* invalid option */
-        break;
-      case 'i':
-        args |= has_i;  /* (-i implies -v) *//* FALLTHROUGH */
-      case 'v':
-        if (argv[i][2] != '\0')  /* extra characters? */
-          return has_error;  /* invalid option */
-        args |= has_v;
-        break;
-      case 'e':
-        args |= has_e;  /* FALLTHROUGH */
-      case 'l':  /* both options need an argument */
-        if (argv[i][2] == '\0') {  /* no concatenated argument? */
-          i++;  /* try next 'argv' */
-          if (argv[i] == NULL || argv[i][0] == '-')
-            return has_error;  /* no next argument or it is another option */
-        }
-        break;
-      default:  /* invalid option */
-        return has_error;
-    }
-  }
-  *first = 0;  /* no script name */
-  return args;
-}
-
-
-/*
-** Processes options 'e' and 'l', which involve running Lua code, and
-** 'W', which also affects the state.
-** Returns 0 if some code raises an error.
-*/
-static int runargs (lua_State *L, char **argv, int n) {
-  int i;
-  for (i = 1; i < n; i++) {
-    int option = argv[i][1];
-    lua_assert(argv[i][0] == '-');  /* already checked */
-    switch (option) {
-      case 'e':  case 'l': {
-        int status;
-        char *extra = argv[i] + 2;  /* both options need an argument */
-        if (*extra == '\0') extra = argv[++i];
-        lua_assert(extra != NULL);
-        status = (option == 'e')
-                 ? dostring(L, extra, "=(command line)")
-                 : dolibrary(L, extra);
-        if (status != LUA_OK) return 0;
-        break;
-      }
-      case 'W':
-        lua_warning(L, "@on", 0);  /* warnings on */
-        break;
-    }
-  }
-  return 1;
-}
-
-
-static int handle_luainit (lua_State *L) {
-  const char *name = "=" LUA_INITVARVERSION;
-  const char *init = getenv(name + 1);
-  if (init == NULL) {
-    name = "=" LUA_INIT_VAR;
-    init = getenv(name + 1);  /* try alternative name */
-  }
-  if (init == NULL) return LUA_OK;
-  else if (init[0] == '@')
-    return dofile(L, init+1);
-  else
-    return dostring(L, init, name);
-}
-
-
-/*
-** {==================================================================
-** Read-Eval-Print Loop (REPL)
-** ===================================================================
-*/
-
-#if !defined(LUA_PROMPT)
-#define LUA_PROMPT		"> "
-#define LUA_PROMPT2		">> "
-#endif
-
-#if !defined(LUA_MAXINPUT)
-#define LUA_MAXINPUT		512
-#endif
-
-
-/*
-** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
-** is, whether we're running lua interactively).
-*/
-#if !defined(lua_stdin_is_tty)	/* { */
-
-#if defined(LUA_USE_POSIX)	/* { */
-
-#include <unistd.h>
-#define lua_stdin_is_tty()	isatty(0)
-
-#elif defined(LUA_USE_WINDOWS)	/* }{ */
-
-#include <io.h>
-#include <windows.h>
-
-#define lua_stdin_is_tty()	_isatty(_fileno(stdin))
-
-#else				/* }{ */
-
-/* ISO C definition */
-#define lua_stdin_is_tty()	1  /* assume stdin is a tty */
-
-#endif				/* } */
-
-#endif				/* } */
-
-
-/*
-** lua_readline defines how to show a prompt and then read a line from
-** the standard input.
-** lua_saveline defines how to "save" a read line in a "history".
-** lua_freeline defines how to free a line read by lua_readline.
-*/
-#if !defined(lua_readline)	/* { */
-
-#if defined(LUA_USE_READLINE)	/* { */
-
-#include <readline/readline.h>
-#include <readline/history.h>
-#define lua_initreadline(L)	((void)L, rl_readline_name="lua")
-#define lua_readline(L,b,p)	((void)L, ((b)=readline(p)) != NULL)
-#define lua_saveline(L,line)	((void)L, add_history(line))
-#define lua_freeline(L,b)	((void)L, free(b))
-
-#else				/* }{ */
-
-#define lua_initreadline(L)  ((void)L)
-#define lua_readline(L,b,p) \
-        ((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
-        fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
-#define lua_saveline(L,line)	{ (void)L; (void)line; }
-#define lua_freeline(L,b)	{ (void)L; (void)b; }
-
-#endif				/* } */
-
-#endif				/* } */
-
-
-/*
-** Return the string to be used as a prompt by the interpreter. Leave
-** the string (or nil, if using the default value) on the stack, to keep
-** it anchored.
-*/
-static const char *get_prompt (lua_State *L, int firstline) {
-  if (lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2") == LUA_TNIL)
-    return (firstline ? LUA_PROMPT : LUA_PROMPT2);  /* use the default */
-  else {  /* apply 'tostring' over the value */
-    const char *p = luaL_tolstring(L, -1, NULL);
-    lua_remove(L, -2);  /* remove original value */
-    return p;
-  }
-}
-
-/* mark in error messages for incomplete statements */
-#define EOFMARK		"<eof>"
-#define marklen		(sizeof(EOFMARK)/sizeof(char) - 1)
-
-
-/*
-** Check whether 'status' signals a syntax error and the error
-** message at the top of the stack ends with the above mark for
-** incomplete statements.
-*/
-static int incomplete (lua_State *L, int status) {
-  if (status == LUA_ERRSYNTAX) {
-    size_t lmsg;
-    const char *msg = lua_tolstring(L, -1, &lmsg);
-    if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {
-      lua_pop(L, 1);
-      return 1;
-    }
-  }
-  return 0;  /* else... */
-}
-
-
-/*
-** Prompt the user, read a line, and push it into the Lua stack.
-*/
-static int pushline (lua_State *L, int firstline) {
-  char buffer[LUA_MAXINPUT];
-  char *b = buffer;
-  size_t l;
-  const char *prmt = get_prompt(L, firstline);
-  int readstatus = lua_readline(L, b, prmt);
-  if (readstatus == 0)
-    return 0;  /* no input (prompt will be popped by caller) */
-  lua_pop(L, 1);  /* remove prompt */
-  l = strlen(b);
-  if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
-    b[--l] = '\0';  /* remove it */
-  if (firstline && b[0] == '=')  /* for compatibility with 5.2, ... */
-    lua_pushfstring(L, "return %s", b + 1);  /* change '=' to 'return' */
-  else
-    lua_pushlstring(L, b, l);
-  lua_freeline(L, b);
-  return 1;
-}
-
-
-/*
-** Try to compile line on the stack as 'return <line>;'; on return, stack
-** has either compiled chunk or original line (if compilation failed).
-*/
-static int addreturn (lua_State *L) {
-  const char *line = lua_tostring(L, -1);  /* original line */
-  const char *retline = lua_pushfstring(L, "return %s;", line);
-  int status = luaL_loadbuffer(L, retline, strlen(retline), "=stdin");
-  if (status == LUA_OK) {
-    lua_remove(L, -2);  /* remove modified line */
-    if (line[0] != '\0')  /* non empty? */
-      lua_saveline(L, line);  /* keep history */
-  }
-  else
-    lua_pop(L, 2);  /* pop result from 'luaL_loadbuffer' and modified line */
-  return status;
-}
-
-
-/*
-** Read multiple lines until a complete Lua statement
-*/
-static int multiline (lua_State *L) {
-  for (;;) {  /* repeat until gets a complete statement */
-    size_t len;
-    const char *line = lua_tolstring(L, 1, &len);  /* get what it has */
-    int status = luaL_loadbuffer(L, line, len, "=stdin");  /* try it */
-    if (!incomplete(L, status) || !pushline(L, 0)) {
-      lua_saveline(L, line);  /* keep history */
-      return status;  /* cannot or should not try to add continuation line */
-    }
-    lua_pushliteral(L, "\n");  /* add newline... */
-    lua_insert(L, -2);  /* ...between the two lines */
-    lua_concat(L, 3);  /* join them */
-  }
-}
-
-
-/*
-** Read a line and try to load (compile) it first as an expression (by
-** adding "return " in front of it) and second as a statement. Return
-** the final status of load/call with the resulting function (if any)
-** in the top of the stack.
-*/
-static int loadline (lua_State *L) {
-  int status;
-  lua_settop(L, 0);
-  if (!pushline(L, 1))
-    return -1;  /* no input */
-  if ((status = addreturn(L)) != LUA_OK)  /* 'return ...' did not work? */
-    status = multiline(L);  /* try as command, maybe with continuation lines */
-  lua_remove(L, 1);  /* remove line from the stack */
-  lua_assert(lua_gettop(L) == 1);
-  return status;
-}
-
-
-/*
-** Prints (calling the Lua 'print' function) any values on the stack
-*/
-static void l_print (lua_State *L) {
-  int n = lua_gettop(L);
-  if (n > 0) {  /* any result to be printed? */
-    luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
-    lua_getglobal(L, "print");
-    lua_insert(L, 1);
-    if (lua_pcall(L, n, 0, 0) != LUA_OK)
-      l_message(progname, lua_pushfstring(L, "error calling 'print' (%s)",
-                                             lua_tostring(L, -1)));
-  }
-}
-
-
-/*
-** Do the REPL: repeatedly read (load) a line, evaluate (call) it, and
-** print any results.
-*/
-static void doREPL (lua_State *L) {
-  int status;
-  const char *oldprogname = progname;
-  progname = NULL;  /* no 'progname' on errors in interactive mode */
-  lua_initreadline(L);
-  while ((status = loadline(L)) != -1) {
-    if (status == LUA_OK)
-      status = docall(L, 0, LUA_MULTRET);
-    if (status == LUA_OK) l_print(L);
-    else report(L, status);
-  }
-  lua_settop(L, 0);  /* clear stack */
-  lua_writeline();
-  progname = oldprogname;
-}
-
-/* }================================================================== */
-
-
-/*
-** Main body of stand-alone interpreter (to be called in protected mode).
-** Reads the options and handles them all.
-*/
-static int pmain (lua_State *L) {
-  int argc = (int)lua_tointeger(L, 1);
-  char **argv = (char **)lua_touserdata(L, 2);
-  int script;
-  int args = collectargs(argv, &script);
-  int optlim = (script > 0) ? script : argc; /* first argv not an option */
-  luaL_checkversion(L);  /* check that interpreter has correct version */
-  if (args == has_error) {  /* bad arg? */
-    print_usage(argv[script]);  /* 'script' has index of bad arg. */
-    return 0;
-  }
-  if (args & has_v)  /* option '-v'? */
-    print_version();
-  if (args & has_E) {  /* option '-E'? */
-    lua_pushboolean(L, 1);  /* signal for libraries to ignore env. vars. */
-    lua_setfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
-  }
-  luaL_openlibs(L);  /* open standard libraries */
-  createargtable(L, argv, argc, script);  /* create table 'arg' */
-  lua_gc(L, LUA_GCRESTART);  /* start GC... */
-  lua_gc(L, LUA_GCGEN, 0, 0);  /* ...in generational mode */
-  if (!(args & has_E)) {  /* no option '-E'? */
-    if (handle_luainit(L) != LUA_OK)  /* run LUA_INIT */
-      return 0;  /* error running LUA_INIT */
-  }
-  if (!runargs(L, argv, optlim))  /* execute arguments -e and -l */
-    return 0;  /* something failed */
-  if (script > 0) {  /* execute main script (if there is one) */
-    if (handle_script(L, argv + script) != LUA_OK)
-      return 0;  /* interrupt in case of error */
-  }
-  if (args & has_i)  /* -i option? */
-    doREPL(L);  /* do read-eval-print loop */
-  else if (script < 1 && !(args & (has_e | has_v))) { /* no active option? */
-    if (lua_stdin_is_tty()) {  /* running in interactive mode? */
-      print_version();
-      doREPL(L);  /* do read-eval-print loop */
-    }
-    else dofile(L, NULL);  /* executes stdin as a file */
-  }
-  lua_pushboolean(L, 1);  /* signal no errors */
-  return 1;
-}
-
-
-int main (int argc, char **argv) {
-  int status, result;
-  lua_State *L = luaL_newstate();  /* create state */
-  if (L == NULL) {
-    l_message(argv[0], "cannot create state: not enough memory");
-    return EXIT_FAILURE;
-  }
-  lua_gc(L, LUA_GCSTOP);  /* stop GC while building state */
-  lua_pushcfunction(L, &pmain);  /* to call 'pmain' in protected mode */
-  lua_pushinteger(L, argc);  /* 1st argument */
-  lua_pushlightuserdata(L, argv); /* 2nd argument */
-  status = lua_pcall(L, 2, 1, 0);  /* do the call */
-  result = lua_toboolean(L, -1);  /* get result */
-  report(L, status);
-  lua_close(L);
-  return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
-}
-
-#endif /* LUA_MAKE_LUA */
 
 /*
   MIT License

apps/twnlua/state.h

@@ -1,8 +1,6 @@
 #ifndef STATE_H
 #define STATE_H
 
-#include <lua.h>
-
 #include <stdbool.h>
 
 typedef struct State {

bin/build.sh

@@ -1,19 +0,0 @@
-#!/bin/env sh
-
-set +e
-
-# check whether ninja is around (you better start running)
-if [ -x "$(command -v ninja)" ]; then
-    generator="-G Ninja"
-fi
-
-# check whether clang is around (it's just better)
-if [ -x "$(command -v clang)" ]; then
-    cc="-DCMAKE_C_COMPILER=clang"
-fi
-
-if [ "$1" = "web" ]; then
-    emcmake cmake $generator $cc -B build-web "${@:2}" && cmake --build build-web --parallel
-else
-    cmake $generator $cc -B build "$@" && cmake --build build --parallel
-fi

bin/gen_api_header.sh

@@ -1,6 +1,6 @@
 #!/bin/env sh
 # single header api generator with clang
 
-set +e
+set -e
 
 clang -I./ -P -E -nostdinc -nobuiltininc -DTWN_NOT_C $TWNROOT/include/twn_game_api.h 2> /dev/null | clang-format

bin/prep-embed.sh

@@ -0,0 +1,8 @@
+#!/bin/env sh
+set -e
+# packages embedded resources with objcopy, so that it is more portable
+# ld.lld on windows doesn't recognize --format binary, sadly
+
+objdump=$(objdump -i)
+bdfname=$(echo "$objdump" | sed -n 2p)
+objcopy -I binary -O "$bdfname" share/assets/Dernyns256.ttf "$CMAKE_CURRENT_BINARY_DIR/font.o"

bin/twn

@@ -1,21 +1,34 @@
 #!/bin/env sh
 # townengine tooling interface
 
-set +e
+set -e
 
 exe="$(basename $PWD)"
-toolpath="$(dirname -- "${BASH_SOURCE[0]}")"
+toolpath="$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")"
 export TWNROOT=$(realpath "$toolpath"/../)
 
 case "$1" in
-    build    ) "$toolpath"/build.sh "${@:2}"
+    build    ) "$toolpath"/twnbuild "${@:2}"
                ;;
 
-    run      ) $0 build && ./$exe "${@:2}"
+    run      ) $0 build "${@:2}"
+               if [[ "$*" == *"--target=web"* ]]; then
+                   if [ "$OS" = "Windows_NT" ]; then
+                       explorer "http://0.0.0.0:8000/$exe.html" & python3 -m http.server
+                   else
+                       xdg-open "http://0.0.0.0:8000/$exe.html" & python3 -m http.server
+                   fi
+               else
+                   ./$exe
+               fi
                ;;
 
     gdb      ) unset DEBUGINFOD_URLS
-               $0 build && gdb --se=libgame.so -ex run --args "$(basename $PWD)" "${@:2}"
+               $0 build --debug && gdb --se=libgame.so -ex run --args "$(basename $PWD)" --no-sanity-timer "${@:2}"
+               ;;
+
+    init     ) cp -r "$TWNROOT/apps/templates/$2" "$3"
+               ln -s "$TWNROOT/bin/twn" "$3/twn"
                ;;
 
     apitrace ) case "$2" in
@@ -37,6 +50,16 @@ case "$1" in
     api-gen  ) "$toolpath"/gen_api_header.sh
                ;;
 
+    wiki     ) if [ "$OS" = "Windows_NT" ]; then
+                   explorer "file://""$(cygpath -w "$(command realpath $TWNROOT/docs/wiki/index.html)")"
+               else
+                   xdg-open "file://$TWNROOT/docs/wiki/index.html"
+               fi
+               ;;
+
+    devcompl ) (cd "$TWNROOT" && "$toolpath"/twnbuild "--build_dir=$TWNROOT/build" "${@:2}")
+               ;;
+
     *        ) echo "Unknown command."
                ;;
 esac

bin/twnbuild

@@ -0,0 +1,64 @@
+#!/bin/env python3
+
+from subprocess import getoutput, run
+from os import getcwd
+from os.path import expandvars
+from pathlib import Path
+from sys import argv
+from functools import reduce
+import tomllib
+
+#TODO: support for default pack override
+#TODO: automatic full rebuild on git head change (such as new commits)
+
+has_ninja = getoutput("command -v ninja") != ""
+has_clang = getoutput("command -v clang") != ""
+
+target_web = "--target=web" in argv
+
+#TODO: infer what "native" means for current env
+build_dir_arg = reduce(lambda c, n: c if c.startswith("--build_dir=") else n, argv + [""], "")
+build_dir = "build/web" if target_web else build_dir_arg.split("=")[1] if build_dir_arg else "build/native"
+build_dir += "" if build_dir_arg else "/release" if "--release" in argv else "/debug"
+
+cmake = ["emcmake", "cmake"] if target_web else ["cmake"]
+# cmake configuration command
+command = []
+
+# check whether clang is around (it's just better)
+if has_clang and not target_web:
+    command += ["-DCMAKE_C_COMPILER=clang"]
+# check whether ninja is around (you better start running)
+if has_ninja:
+    command += ["-G", "Ninja"]
+
+command += ["-B", build_dir]
+
+# TODO: have it --fast=1 instead, where separate --debug=0 would mean stripping the debug info
+if "--release" in argv:
+    command += ["-DCMAKE_BUILD_TYPE=Release"]
+elif "--debug" in argv:
+    command += ["-DCMAKE_BUILD_TYPE=Debug"]
+
+if "--unified=1" in argv:
+    command += ["-DTWN_FEATURE_DYNLIB_GAME=ON"]
+elif "--unified=0" in argv:
+    command += ["-DTWN_FEATURE_DYNLIB_GAME=OFF"]
+
+if "--sanitize=1" in argv:
+    command += ["-DTWN_SANITIZE=ON"]
+elif "--sanitize=0" in argv:
+    command += ["-DTWN_SANITIZE=OFF"]
+
+command += [f"-DTWN_OUT_DIR={getcwd()}"]
+# pass arbitrary arguments over
+if "--" in argv:
+    command += argv[argv.index("--")+1:]
+
+# if no root cmake file is present, infer it from `twn.toml:game.interpreter`
+if not Path("CMakeLists.txt").is_file():
+    config = tomllib.loads(Path("data/twn.toml").read_text())
+    command += ["-S", expandvars(config["game"]["interpreter"])]
+
+run(cmake + command, check=True)
+run(["cmake"] + ["--build", build_dir, "--parallel"], check=True)