rendering.c: non-square rotating sprites

src/game/scenes/ingame.c

@@ -37,6 +37,11 @@ static void ingame_tick(struct state *state) {
         .path = "/assets/player/baron-walk.png",
         .color = (t_color){255, 255, 255, 255}, });
 
+    push_sprite_ex((t_frect){ .x = 128, .y = 32, .w = 128, .h = 64 }, (t_push_sprite_args){
+        .path = "/assets/player/baron-walk.png",
+        .color = (t_color){255, 255, 255, 255},
+        .rotation = (float)M_PI * 2 * (float)(ctx.tick_count % 64) / 64, });
+
     unfurl_triangle("/assets/big-violet.png",
                     (t_fvec3){ -1, -1, 0 },
                     (t_fvec3){ 1, -1, 0 },

src/rendering/sprites.h

@@ -241,7 +241,15 @@ static void render_sprites(const struct primitive_2d primitives[],
             } else {
                 /* rotated non-square case*/
 
-                CRY("Rotation", "Unimplemented");
+                const t_fvec2 c = frect_center(sprite.rect);
+                const t_fvec2 t = fast_cossine(sprite.rotation);
+
+                const t_fvec2 h = { sprite.rect.w / 2, sprite.rect.h / 2 };
+
+                v0 = (t_fvec2){ c.x + t.x * -h.x - t.y * -h.y, c.y + t.y * -h.x + t.x * -h.y };
+                v1 = (t_fvec2){ c.x + t.x * -h.x - t.y * +h.y, c.y + t.y * -h.x + t.x * +h.y };
+                v2 = (t_fvec2){ c.x + t.x * +h.x - t.y * +h.y, c.y + t.y * +h.x + t.x * +h.y };
+                v3 = (t_fvec2){ c.x + t.x * +h.x - t.y * -h.y, c.y + t.y * +h.x + t.x * -h.y };
             }
 
             if (!batch.constant_colored)