/apps/demos/crawl: visuals and stuff

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

@@ -0,0 +1,32 @@
+@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
+. stone_floor
+  tile_texture : /assets/pebbles.png
+@ player_spawn
+  unique :
+  face : south
+  hold : torch
+  tile_texture : /assets/pebbles.png
+X door
+  open_on_signal : sg_torch0
+  tile_texture : /assets/pebbles.png
+/ lever
+  on_interact_emit : sg_torch0
+  tile_texture : /assets/pebbles.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 +1,64 @@
+require("string")
+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 direction = { x = 0, z = 0 }
+    if input_action_just_released { name = "walk_forward" } then
+        direction = { x = direction.x + ctx.udata.player.direction.z, z = direction.z + ctx.udata.player.direction.x }
+    end
+    if input_action_just_released { name = "walk_backward" } then
+        direction = { x = direction.x - ctx.udata.player.direction.z, z = direction.z - ctx.udata.player.direction.x }
+    end
+
+    ctx.udata.player.position = { x = ctx.udata.player.position.x + direction.x, y = ctx.udata.player.position.y + direction.z }
+
+    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.y * 2 + 1,
+            y = 1,
+            z = ctx.udata.player.position_lerp.x * 2 + 1,
+        },
+        direction = ctx.udata.player.direction_lerp,
+    }
+
+    render_dungeon(ctx.udata.level)
+end

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

@@ -0,0 +1,87 @@
+
+function load_level(file)
+    local f = file_read { file = file }
+
+    local result = {
+        classes = {
+            void = { },
+        },
+        glossary = {
+            [" "] = "void",
+        },
+        grid = {},
+        map = {},
+        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
+            local l = #result.map + 1
+            if result.size.x < #line then
+                result.size.x = #line
+            end
+            result.map[l] = {}
+            for i = 1, #line do
+                result.map[l][i] = line:sub(i,i)
+            end
+        -- 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
+    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][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 +1,59 @@
+
+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 = y * 2,     y = 2, z = x * 2 },
+                    v2 = { x = y * 2,     y = 0, z = x * 2 },
+                    v1 = { x = y * 2 + 2, y = 0, z = x * 2 },
+                    v0 = { x = y * 2 + 2, y = 2, z = x * 2 },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = y * 2 + 2, y = 2, z = x * 2 },
+                    v2 = { x = y * 2 + 2, y = 0, z = x * 2 },
+                    v1 = { x = y * 2 + 2, y = 0, z = x * 2 + 2 },
+                    v0 = { x = y * 2 + 2, y = 2, z = x * 2 + 2 },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = y * 2 + 2, y = 2, z = x * 2 + 2 },
+                    v2 = { x = y * 2 + 2, y = 0, z = x * 2 + 2 },
+                    v1 = { x = y * 2,     y = 0, z = x * 2 + 2 },
+                    v0 = { x = y * 2,     y = 2, z = x * 2 + 2 },
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].wall_texture,
+                    v3 = { x = y * 2,     y = 2, z = x * 2 + 2 },
+                    v2 = { x = y * 2,     y = 0, z = x * 2 + 2 },
+                    v1 = { x = y * 2,     y = 0, z = x * 2 },
+                    v0 = { x = y * 2,     y = 2, z = x * 2 },
+                    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 = y * 2 + 2, y = 0, z = x * 2 },
+                    v1 = { x = y * 2,     y = 0, z = x * 2 },
+                    v2 = { x = y * 2,     y = 0, z = x * 2 + 2 },
+                    v3 = { x = y * 2 + 2, y = 0, z = x * 2 + 2},
+                    texture_region = { w = 128, h = 128 },
+                }
+                draw_quad {
+                    texture = dungeon.grid[y][x].tile_texture,
+                    v3 = { x = y * 2 + 2, y = 2, z = x * 2 },
+                    v2 = { x = y * 2,     y = 2, z = x * 2 },
+                    v1 = { x = y * 2,     y = 2, z = x * 2 + 2 },
+                    v0 = { x = y * 2 + 2, y = 2, z = x * 2 + 2},
+                    texture_region = { w = 128, h = 128 },
+                }
+            end
+        end
+    end
+end

apps/demos/crawl/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/demos/scenery/scenes/ingame.c

@@ -179,7 +179,7 @@ static void draw_terrain(SceneIngame *scn) {
             draw_billboard("/assets/grasses/10.png",
                           (Vec3){ (float)x, d0 + 0.15f, (float)y },
                           (Vec2){0.3f, 0.3f},
-                          NULL,
+                          (Rect){0},
                           (Color){255, 255, 255, 255}, true);
         }
     }

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

@@ -1,8 +1,7 @@
 -- called every frame, with constant delta time
 function game_tick()
-    -- ctx.initialization_needed is true first frame and every time dynamic reload is performed
-    if ctx.initialization_needed then
-        -- ctx.udata persists on reload
+    -- ctx.udata persists on code reload
+    if ctx.udata == nil then
         ctx.udata = {}
     end
 end

apps/twnlua/game.c

@@ -25,6 +25,12 @@ void bindgen_upload_context(lua_State *L);
 static int physfs_loader(lua_State *L) {
     const char *name = luaL_checkstring(L, 1);
 
+    static const char *name_breaker = NULL;
+    if (name_breaker && SDL_strcmp(name, name_breaker) == 0) {
+        log_critical("Recursive load on itself from lua module (%s)", name_breaker);
+        return 0;
+    } name_breaker = name;
+
     /* replace dots with path slashes */
     char *path_copy = SDL_strdup(name);
     char *ch = NULL;

docs/wiki/about-townengine.html

@@ -54,14 +54,15 @@
       <li><b>G</b> for gamedev; guides and FAQs on game making.
       </ul>
     </blockquote>
-    <p><a name="abi"></a><strong>T1.3 </strong><strong>ABI</strong>
+    <p><a name="abi"></a><strong>T1.3 </strong><strong>Procedure Interface</strong>
     <blockquote>
-      <p>For native code ABI defines convention to ease tooling integration.
+      <p>For native code ABI defines convention to ease tooling integration. Platform/compiler C ABI is assumed,
+         but it should be trivially expressible in JSON-RPC as well.
       <ul>
       <li>32 bit floating point is the only numeric type.
       <li>Procedure parameters can only use basic types, with no aggregates. Exceptions are Vec, Rect and Color types.
           (see /include/twn_types.h)
-      <li>Enum types are not allowed, as they decay to integer type, identity strings are used instead.
+      <li>Enum types are allowed, but must be converted to floats. Identity strings are preferred.
       <li>No opaque nor pointer types allowed, use string keys if needed. Think of it as data base relations.
       <li>Only null terminated string is allowed as a sequential type in both parameters and returns.
       <li>Return value could be a simple aggregate that is translatable to a dictionary of primitives, without nesting.
@@ -70,6 +71,8 @@
       <li>Parameter names should not collide with keywords of any language that is targeted; if so happens, parameter alias could be added.
           Currently forbidden: <b>repeat</b>.
       <li>Procedure can't have more than 8 parameters.
+      <li>Decimal portions of floating points are lossy both due to rounding errors and text representation,
+          thus they cannot be relied to hold for equality. Integer parts of floats are good up to 2^24.
       </ul>
     </blockquote>
   </body>

docs/wiki/index.html

@@ -20,6 +20,7 @@
     <blockquote style="margin-top:0">
         <p style="margin:0">T1.1 <a href="about-townengine.html#introduction">Introduction</a></p>
         <p style="margin:0">T1.2 <a href="about-townengine.html#wiki">Wiki</a></p>
+        <p style="margin:0">T1.3 <a href="about-townengine.html#abi">Procedure Interface</a></p>
     </blockquote>
     <p style="margin-bottom:0"><a name="input-system"></a>T2. </strong><a href="input-system.html">Input System</strong></a></p>
     <blockquote style="margin-top:0">

include/twn_draw.h

@@ -10,7 +10,7 @@
 /* TODO: combine flip_x and flip_y into a flip_mask with enum */
 TWN_API void draw_sprite(char const *texture,
                          Rect        rect,
-                         Rect const *texture_region,    /* optional, default: NULL */
+                         Rect        texture_region,    /* optional, default: all 0 */
                          Color       color,             /* optional, default: all 255 */
                          float       rotation,          /* optional, default: 0 */
                          bool        flip_x,            /* optional, default: false */
@@ -76,8 +76,8 @@ TWN_API void draw_quad(char const *texture,
 TWN_API void draw_billboard(char const *texture,
                             Vec3        position,
                             Vec2        size,
-                            Rect const *texture_region, /* optional, default: NULL */
-                            Color       color,          /* optional, default: all 255 */
+                            Rect        texture_region, /* optional, default: NULL */
+                            Color       color,          /* optional, default: all 0 */
                             bool        cylindrical);   /* optional, default: false */
 
 TWN_API void draw_camera_2d(Vec2 position,      /* optional, default: (0, 0) */

include/twn_util.h

@@ -42,6 +42,9 @@
 
 #endif /* TWN_NOT_C */
 
+/* read file to null terminated string, it is freed when the frame ends */
+TWN_API char const *file_read(char const *file);
+
 /* calculates the overlap of two rectangles */
 TWN_API Rect rect_overlap(Rect a, Rect b);
 /* returns true if two rectangles are intersecting */

share/twn_api.json

@@ -59,7 +59,7 @@
             "params": [
                 { "name": "texture", "type": "char *" },
                 { "name": "rect", "type": "Rect" },
-                { "name": "texture_region", "type": "Rect *", "default": {} },
+                { "name": "texture_region", "type": "Rect", "default": { "x": 0, "y": 0, "w": 0, "h": 0 } },
                 { "name": "color", "type": "Color", "default": { "r": 255, "g": 255, "b": 255, "a": 255 } },
                 { "name": "rotation", "type": "float", "default": 0.0 },
                 { "name": "flip_x", "type": "bool", "default": false },
@@ -180,7 +180,7 @@
                 { "name": "texture", "type": "char *" },
                 { "name": "position", "type": "Vec3" },
                 { "name": "size", "type": "Vec2" },
-                { "name": "texture_region", "type": "Rect *", "default": {} },
+                { "name": "texture_region", "type": "Rect", "default": { "x": 0, "y": 0, "w": 0, "h": 0 } },
                 { "name": "color", "type": "Color", "default": { "r": 255, "g": 255, "b": 255, "a": 255 } },
                 { "name": "cylindrical", "type": "bool", "default": false }
             ]
@@ -264,6 +264,16 @@
             ]
         },
 
+        "file_read": {
+            "module": "util",
+            "symbol": "read",
+            "header": "twn_util.h",
+            "params": [
+                { "name": "file", "type": "char *" }
+            ],
+            "return": "char *"
+        },
+
         "timer_tick_seconds": {
             "module": "util",
             "symbol": "tick_seconds",
@@ -298,7 +308,7 @@
             "header": "twn_util.h",
             "params": [
                 { "name": "value", "type": "Vec2" },
-                { "name": "identity", "type": "char *" }
+                { "name": "identity", "type": "char *", "default": {} }
             ]
         },
 
@@ -308,7 +318,7 @@
             "header": "twn_util.h",
             "params": [
                 { "name": "value", "type": "Vec3" },
-                { "name": "identity", "type": "char *" }
+                { "name": "identity", "type": "char *", "default": {} }
             ]
         },
 
@@ -318,7 +328,7 @@
             "header": "twn_util.h",
             "params": [
                 { "name": "value", "type": "Rect" },
-                { "name": "identity", "type": "char *" }
+                { "name": "identity", "type": "char *", "default": {} }
             ]
         },
 

src/rendering/twn_billboards.c

@@ -12,7 +12,7 @@
 void draw_billboard(char const *texture,
                     Vec3 position,
                     Vec2 size,
-                    Rect const *texture_region,
+                    Rect texture_region,
                     Color color,
                     bool cylindrical)
 {
@@ -26,16 +26,19 @@ void draw_billboard(char const *texture,
         batch_p = &ctx.billboard_batches[hmlenu(ctx.billboard_batches) - 1]; /* TODO: can last index be used? */
     }
 
+    bool const texture_region_valid = fabsf(texture_region.w - texture_region.h) > 0.00001f
+                                   && fabsf(0.0f - texture_region.w) > 0.00001f;
+
     struct SpaceBillboard billboard = {
         .color = color,
         .cylindrical = cylindrical,
         .position = position,
         .size = size,
-        .texture_region_opt_set = texture_region != NULL,
+        .texture_region_opt_set = texture_region_valid,
     };
 
-    if (texture_region)
-        billboard.texture_region_opt = *texture_region;
+    if (texture_region_valid)
+        billboard.texture_region_opt = texture_region;
 
     struct SpaceBillboard *billboards = (struct SpaceBillboard *)(void *)batch_p->value.primitives;
 

src/rendering/twn_sprites.c

@@ -19,13 +19,18 @@
  */
 void draw_sprite(char const *path,
                  Rect        rect,
-                 Rect const *texture_region,    /* optional, default: NULL */
+                 Rect        texture_region,    /* optional, default: 0 */
                  Color       color,             /* optional, default: all 255 */
                  float       rotation,          /* optional, default: 0 */
                  bool        flip_x,            /* optional, default: false */
                  bool        flip_y,            /* optional, default: false */
                  bool        stretch)
 {
+    /* if .w and .h are zeroed then assume whole region */
+    /* TODO: don't check here, just move to redner code ? */
+    bool const texture_region_valid = fabsf(texture_region.w - texture_region.h) > 0.00001f
+                                   && fabsf(0.0f - texture_region.w) > 0.00001f;
+
     SpritePrimitive sprite = {
         .rect = rect,
         .color = color,
@@ -34,11 +39,11 @@ void draw_sprite(char const *path,
         .flip_x = flip_x,
         .flip_y = flip_y,
         .repeat = !stretch,
-        .texture_region_opt_set = texture_region != NULL,
+        .texture_region_opt_set = texture_region_valid,
     };
 
-    if (texture_region)
-        sprite.texture_region_opt = *texture_region;
+    if (texture_region_valid)
+        sprite.texture_region_opt = texture_region;
 
     Primitive2D primitive = {
         .type = PRIMITIVE_2D_SPRITE,
@@ -54,7 +59,7 @@ void draw_sprite_args(const DrawSpriteArgs args) {
     bool const flip_x = m_or(args, flip_x, false);
     bool const flip_y = m_or(args, flip_y, false);
     bool const stretch = m_or(args, stretch, false);
-    Rect const *texture_region = m_is_set(args, texture_region) ? &args.texture_region_opt : NULL;
+    Rect const texture_region = m_or(args, texture_region, ((Rect){0}));
 
     draw_sprite(args.texture, args.rect, texture_region, color, rotation, flip_x, flip_y, stretch);
 }

src/twn_loop.c

@@ -754,6 +754,11 @@ static bool try_mounting_root_pack(char *path) {
 }
 
 
+static void garbage_collect(void) {
+    file_read_garbage_collect();
+}
+
+
 int enter_loop(int argc, char **argv) {
     profile_start("startup");
 
@@ -866,6 +871,7 @@ int enter_loop(int argc, char **argv) {
         /* dispatch all filewatch driven events, such as game object and asset pack reload */
         filewatch_poll();
         main_loop();
+        garbage_collect();
     }
 
     if (ctx.game.debug)

src/twn_util.c

@@ -154,6 +154,24 @@ char *file_to_str(const char *path) {
     return str_out;
 }
 
+static char **read_files;
+
+char const *file_read(char const *file) {
+    char *s = file_to_str(file);
+
+    if (s) arrpush(read_files, s);
+
+    return s;
+}
+
+
+void file_read_garbage_collect(void) {
+    for (size_t i = 0; i < arrlenu(read_files); ++i)
+        SDL_free(read_files[i]);
+    arrfree(read_files);
+    read_files = NULL;
+}
+
 
 bool file_exists(const char *path) {
     return PHYSFS_exists(path);

src/twn_util_c.h

@@ -29,6 +29,8 @@ char *expand_asterisk(const char *mask, const char *to);
 
 void profile_list_stats(void);
 
+void file_read_garbage_collect(void);
+
 /* http://www.azillionmonkeys.com/qed/sqroot.html */
 static inline float fast_sqrt(float x)
 {

third-party/fast_obj/fast_obj.h

@@ -297,58 +297,6 @@ static void* array_realloc(void* ptr, fastObjUInt n, fastObjUInt b)
 }
 
 
-static
-void* file_open(const char* path, void* user_data)
-{
-    (void)(user_data);
-    return fopen(path, "rb");
-}
-
-
-static
-void file_close(void* file, void* user_data)
-{
-    FILE* f;
-    (void)(user_data);
-    
-    f = (FILE*)(file);
-    fclose(f);
-}
-
-
-static
-size_t file_read(void* file, void* dst, size_t bytes, void* user_data)
-{
-    FILE* f;
-    (void)(user_data);
-    
-    f = (FILE*)(file);
-    return fread(dst, 1, bytes, f);
-}
-
-
-static
-unsigned long file_size(void* file, void* user_data)
-{
-    FILE* f;
-    long p;
-    long n;
-    (void)(user_data);
-
-    f = (FILE*)(file);
-
-    p = ftell(f);
-    fseek(f, 0, SEEK_END);
-    n = ftell(f);
-    fseek(f, p, SEEK_SET);
-
-    if (n > 0)
-        return (unsigned long)(n);
-    else
-        return 0;
-}
-
-
 static
 char* string_copy(const char* s, const char* e)
 {
@@ -1408,18 +1356,6 @@ void fast_obj_destroy(fastObjMesh* m)
 }
 
 
-fastObjMesh* fast_obj_read(const char* path)
-{
-    fastObjCallbacks callbacks;
-    callbacks.file_open = file_open;
-    callbacks.file_close = file_close;
-    callbacks.file_read = file_read;
-    callbacks.file_size = file_size;
-
-    return fast_obj_read_with_callbacks(path, &callbacks, 0);
-}
-
-
 fastObjMesh* fast_obj_read_with_callbacks(const char* path, const fastObjCallbacks* callbacks, void* user_data)
 {
     fastObjData  data;