remove indirection in vertex builder

src/rendering/twn_billboards.c

@@ -125,9 +125,11 @@ void finally_draw_billboard_batch(struct MeshBatch const *batch,
                 .v3 = vec3_add(billboard.position, a),
             };
 
-            push_to_vertex_buffer_builder(&builder, &payload, sizeof (payload));
+            ((struct ElementIndexedBillboard *)builder.base)[i] = payload;
         }
 
+        finish_vertex_builder(&builder);
+
         /* commit to drawing */
         DeferredCommandDraw command = {0};
 

src/rendering/twn_draw_c.h

@@ -37,9 +37,7 @@ enum {
 typedef uint32_t VertexBuffer;
 
 typedef struct VertexBufferBuilder {
-    size_t bytes_left;
     size_t size;
-    void *mapping;
     void *base;
 } VertexBufferBuilder;
 
@@ -271,10 +269,7 @@ void specify_vertex_buffer(VertexBuffer buffer, void const *data, size_t bytes);
 /* uses present in 1.5 buffer mapping feature */
 VertexBufferBuilder build_vertex_buffer(VertexBuffer buffer, size_t bytes);
 
-/* collects bytes for sending to the gpu until all is pushed, which is when false is returned */
+void finish_vertex_builder(VertexBufferBuilder *builder);
-bool push_to_vertex_buffer_builder(VertexBufferBuilder *builder,
-                                   void const *bytes,
-                                   size_t size);
 
 /* state */
 
@@ -301,7 +296,8 @@ void finally_render_quads(Primitive2D const primitives[],
 
 size_t get_quad_payload_size(struct QuadBatch batch);
 
-bool push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
+void push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
+                                                size_t index,
                                                 VertexBufferBuilder *builder,
                                                 Vec2 v0, Vec2 v1, Vec2 v2, Vec2 v3,
                                                 Vec2 uv0, Vec2 uv1, Vec2 uv2, Vec2 uv3,
@@ -313,12 +309,6 @@ void finally_draw_uncolored_space_traingle_batch(MeshBatch const *batch,
 void finally_draw_billboard_batch(MeshBatch const *batch,
                                   TextureKey texture_key);
 
-size_t get_text_payload_size(void);
-
-bool push_text_payload_to_vertex_buffer_builder(FontData const *font_data,
-                                                VertexBufferBuilder *builder,
-                                                stbtt_aligned_quad quad);
-
 void finally_draw_text(FontData const *font_data,
                        size_t len,
                        Color color,

src/rendering/twn_gl_15_rendering.c

@@ -218,29 +218,18 @@ VertexBufferBuilder build_vertex_buffer(VertexBuffer buffer, size_t bytes) {
         CRY("build_vertex_buffer", "Error mapping a vertex array buffer");
 
     return (VertexBufferBuilder) {
-        .mapping = mapping,
+        .base = mapping,
-        .bytes_left = bytes,
+        .size = bytes,
     };
 }
 
 
-bool push_to_vertex_buffer_builder(VertexBufferBuilder *builder,
+void finish_vertex_builder(VertexBufferBuilder *builder) {
-                                   void const *bytes, size_t size) {
+    glUnmapBuffer(GL_ARRAY_BUFFER);
-    if (builder->bytes_left == 0)
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
-        return false;
 
-    memcpy(builder->mapping, bytes, size);
+    builder->base = 0;
-    builder->bytes_left -= size;
+    builder->size = 0;
-
-    /* trigger data send */
-    if (builder->bytes_left == 0) {
-        glUnmapBuffer(GL_ARRAY_BUFFER);
-        return false;
-    }
-
-    builder->mapping = (void *)((uintptr_t)builder->mapping + size);
-
-    return true;
 }
 
 

src/rendering/twn_gl_any_rendering.c

@@ -44,16 +44,15 @@ VertexBuffer get_quad_element_buffer(void) {
         VertexBufferBuilder builder = build_vertex_buffer(buffer, sizeof (GLshort) * QUAD_ELEMENT_BUFFER_LENGTH * 6 );
 
         for (size_t i = 0; i < QUAD_ELEMENT_BUFFER_LENGTH; ++i) {
-            GLshort indices[6];
+            ((GLshort *)builder.base)[i * 6 + 0] = (GLshort)(i * 4 + 0);
-            indices[0] = (GLshort)(i * 4 + 0);
+            ((GLshort *)builder.base)[i * 6 + 1] = (GLshort)(i * 4 + 1);
-            indices[1] = (GLshort)(i * 4 + 1);
+            ((GLshort *)builder.base)[i * 6 + 2] = (GLshort)(i * 4 + 2);
-            indices[2] = (GLshort)(i * 4 + 2);
+            ((GLshort *)builder.base)[i * 6 + 3] = (GLshort)(i * 4 + 2);
-            indices[3] = (GLshort)(i * 4 + 2);
+            ((GLshort *)builder.base)[i * 6 + 4] = (GLshort)(i * 4 + 3);
-            indices[4] = (GLshort)(i * 4 + 3);
+            ((GLshort *)builder.base)[i * 6 + 5] = (GLshort)(i * 4 + 0);
-            indices[5] = (GLshort)(i * 4 + 0);
-
-            push_to_vertex_buffer_builder(&builder, indices, sizeof indices);
         }
+
+        finish_vertex_builder(&builder);
     }
 
     SDL_assert_always(buffer);
@@ -71,17 +70,14 @@ VertexBuffer get_circle_element_buffer(void) {
 
         for (size_t i = 1; i < CIRCLE_VERTICES_MAX - 1; ++i) {
             /* first one is center point index, always zero */
-            GLshort indices[3];
+            ((GLshort *)builder.base)[(i - 1) * 3 + 0] = 0;
-
-            indices[0] = 0;
 
             /* generated point index */
-            indices[1] = (GLshort)i;
+            ((GLshort *)builder.base)[(i - 1) * 3 + 1] = (GLshort)i;
-
+            ((GLshort *)builder.base)[(i - 1) * 3 + 2] = (GLshort)i + 1;
-            indices[2] = (GLshort)i + 1;
-
-            push_to_vertex_buffer_builder(&builder, indices, sizeof indices);
         }
+
+        finish_vertex_builder(&builder);
     }
 
     SDL_assert_always(buffer);

src/rendering/twn_quads.c

@@ -101,14 +101,15 @@ size_t get_quad_payload_size(struct QuadBatch batch) {
 }
 
 
-bool push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
+void push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
+                                                size_t index,
                                                 VertexBufferBuilder *builder,
                                                 Vec2 v0, Vec2 v1, Vec2 v2, Vec2 v3,
                                                 Vec2 uv0, Vec2 uv1, Vec2 uv2, Vec2 uv3,
                                                 Color color)
 {
     if (!batch.constant_colored && batch.textured) {
-        ElementIndexedQuad const buffer_element = {
+        ElementIndexedQuad const payload = {
             .v0 = v0,
             .v1 = v1,
             .v2 = v2,
@@ -126,10 +127,10 @@ bool push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
             // .c3 = color,
         };
 
-        return push_to_vertex_buffer_builder(builder, &buffer_element, sizeof buffer_element);
+        ((ElementIndexedQuad *)builder->base)[index] = payload;
 
     } else if (batch.constant_colored && batch.textured) {
-        ElementIndexedQuadWithoutColor const buffer_element = {
+        ElementIndexedQuadWithoutColor const payload = {
             .v0 = v0,
             .v1 = v1,
             .v2 = v2,
@@ -141,10 +142,10 @@ bool push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
             .uv3 = uv3,
         };
 
-        return push_to_vertex_buffer_builder(builder, &buffer_element, sizeof buffer_element);
+        ((ElementIndexedQuadWithoutColor *)builder->base)[index] = payload;
 
     } else if (!batch.constant_colored && !batch.textured) {
-        ElementIndexedQuadWithoutTexture const buffer_element = {
+        ElementIndexedQuadWithoutTexture const payload = {
             .v0 = v0,
             .v1 = v1,
             .v2 = v2,
@@ -157,19 +158,18 @@ bool push_quad_payload_to_vertex_buffer_builder(struct QuadBatch batch,
             // .c3 = color,
         };
 
-        return push_to_vertex_buffer_builder(builder, &buffer_element, sizeof buffer_element);
+        ((ElementIndexedQuadWithoutTexture *)builder->base)[index] = payload;
 
     } else if (batch.constant_colored && !batch.textured) {
-        ElementIndexedQuadWithoutColorWithoutTexture const buffer_element = {
+        ElementIndexedQuadWithoutColorWithoutTexture const payload = {
             .v0 = v0,
             .v1 = v1,
             .v2 = v2,
             .v3 = v3,
         };
 
-        return push_to_vertex_buffer_builder(builder, &buffer_element, sizeof buffer_element);
+        ((ElementIndexedQuadWithoutColorWithoutTexture *)builder->base)[index] = payload;
     }
 
     SDL_assert(false);
-    return false;
 }

src/rendering/twn_rects.c

@@ -85,7 +85,7 @@ void render_rect_batch(const Primitive2D primitives[],
             Vec2 v3 = { rect.rect.x + rect.rect.w, rect.rect.y };
 
             push_quad_payload_to_vertex_buffer_builder(
-                batch, &payload,
+                batch, i, &payload,
                 v0, v1, v2, v3,
                 (Vec2){0}, (Vec2){0}, (Vec2){0}, (Vec2){0},
                 rect.color);

src/rendering/twn_sprites.c

@@ -242,7 +242,7 @@ void render_sprite_batch(const Primitive2D primitives[],
                 v3 = (Vec2){ c.x + t.x * +h.x - t.y * -h.y, c.y + t.y * +h.x + t.x * -h.y };
             }
 
-            push_quad_payload_to_vertex_buffer_builder(batch, &payload, v0, v1, v2, v3, uv0, uv1, uv2, uv3, sprite.color);
+            push_quad_payload_to_vertex_buffer_builder(batch, i, &payload, v0, v1, v2, v3, uv0, uv1, uv2, uv3, sprite.color);
         }
     }
 

src/rendering/twn_text.c

@@ -175,7 +175,7 @@ static void text_draw_with(FontData* font_data, char* text, Vec2 position, Color
 
     const size_t len = SDL_strlen(text);
 
-    VertexBufferBuilder payload = build_vertex_buffer(vertex_array, sizeof (ElementIndexedQuadWithoutColor) * len);
+    VertexBufferBuilder builder = build_vertex_buffer(vertex_array, sizeof (ElementIndexedQuadWithoutColor) * len);
 
     for (size_t i = 0; i < len; ++i) {
         const char c = text[i];
@@ -204,9 +204,22 @@ static void text_draw_with(FontData* font_data, char* text, Vec2 position, Color
         quad.y0 += (float)font_data->ascent;
         quad.y1 += (float)font_data->ascent;
 
-        push_text_payload_to_vertex_buffer_builder(font_data, &payload, quad);
+        ElementIndexedQuadWithoutColor const payload = {
+            .v0 = (Vec2){ quad.x0, quad.y0 },
+            .v1 = (Vec2){ quad.x1, quad.y0 },
+            .v2 = (Vec2){ quad.x1, quad.y1 },
+            .v3 = (Vec2){ quad.x0, quad.y1 },
+
+            .uv0 = (Vec2){ quad.s0, quad.t0 },
+            .uv1 = (Vec2){ quad.s1, quad.t0 },
+            .uv2 = (Vec2){ quad.s1, quad.t1 },
+            .uv3 = (Vec2){ quad.s0, quad.t1 },
+        };
+
+        ((ElementIndexedQuadWithoutColor *)builder.base)[i] = payload;
     }
 
+    finish_vertex_builder(&builder);
     finally_draw_text(font_data, len, color, vertex_array);
 }
 
@@ -320,28 +333,6 @@ float draw_text_width(const char *string, float height, const char *font) {
 }
 
 
-bool push_text_payload_to_vertex_buffer_builder(FontData const *font_data,
-                                                VertexBufferBuilder *builder,
-                                                stbtt_aligned_quad quad)
-{
-    (void)font_data;
-
-    ElementIndexedQuadWithoutColor buffer_element = {
-        .v0 = (Vec2){ quad.x0, quad.y0 },
-        .v1 = (Vec2){ quad.x1, quad.y0 },
-        .v2 = (Vec2){ quad.x1, quad.y1 },
-        .v3 = (Vec2){ quad.x0, quad.y1 },
-
-        .uv0 = (Vec2){ quad.s0, quad.t0 },
-        .uv1 = (Vec2){ quad.s1, quad.t0 },
-        .uv2 = (Vec2){ quad.s1, quad.t1 },
-        .uv3 = (Vec2){ quad.s0, quad.t1 },
-    };
-
-    return push_to_vertex_buffer_builder(builder, &buffer_element, sizeof buffer_element);
-}
-
-
 void finally_draw_text(FontData const *font_data,
                        size_t len,
                        Color color,