From f2bbc1863e86e3d59a77ef0771fc0953e795fbea Mon Sep 17 00:00:00 2001
From: veclavtalica <veclavtalica@poto.cafe>
Date: Tue, 15 Oct 2024 18:43:02 +0300
Subject: [PATCH] cache sprite srcrects

---
 src/rendering/twn_sprites.c | 13 ++++++++++---
 src/twn_textures_c.h        |  1 +
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/rendering/twn_sprites.c b/src/rendering/twn_sprites.c
index 32e4704..acaa540 100644
--- a/src/rendering/twn_sprites.c
+++ b/src/rendering/twn_sprites.c
@@ -130,6 +130,10 @@ void render_sprite_batch(const Primitive2D primitives[],
     const Rect dims =
         textures_get_dims(&ctx.texture_cache, primitives->sprite.texture_key);
 
+    /* cached srcrect */
+    Rect cached_srcrect;
+    TextureKey cached_srcrect_key = TEXTURE_KEY_INVALID;
+
     /* vertex population over a vertex buffer builder interface */
     {
         VertexBufferBuilder payload = build_vertex_buffer(vertex_array, get_quad_payload_size(batch) * batch.size);
@@ -139,9 +143,12 @@ void render_sprite_batch(const Primitive2D primitives[],
             const size_t cur = batch.mode == TEXTURE_MODE_GHOSTLY ? i : batch.size - i - 1;
             const SpritePrimitive sprite = primitives[cur].sprite;
 
-            /* TODO: try caching it */
-            const Rect srcrect =
-                textures_get_srcrect(&ctx.texture_cache, primitives[cur].sprite.texture_key);
+            if (primitives[cur].sprite.texture_key.id != cached_srcrect_key.id) {
+                cached_srcrect = textures_get_srcrect(&ctx.texture_cache, primitives[cur].sprite.texture_key);
+                cached_srcrect_key = primitives[cur].sprite.texture_key;
+            }
+
+            Rect const srcrect = cached_srcrect;
 
             Vec2 uv0, uv1, uv2, uv3;
 
diff --git a/src/twn_textures_c.h b/src/twn_textures_c.h
index c76a8c6..081d1f4 100644
--- a/src/twn_textures_c.h
+++ b/src/twn_textures_c.h
@@ -50,6 +50,7 @@ typedef struct TextureCache {
 typedef struct TextureKey { uint16_t id; } TextureKey;
 
 /* tests whether given key structure corresponds to any texture */
+#define TEXTURE_KEY_INVALID (TextureKey) { (uint16_t)-1 }
 #define m_texture_key_is_valid(p_key) ((p_key).id != (uint16_t)-1)
 
 void textures_cache_init(struct TextureCache *cache, SDL_Window *window);