Halve tile struct size from 6 bytes to 3 bytes

include/keraforge/world.h

···
 
 #define KF_TILE_SIZE_PX 16
 
-#define KF_TILEID_MAX UINT16_MAX
+#define KF_TILE_IDWIDTH 10
+#define KF_TILE_DATAWIDTH 4
+
+#define KF_TILEID_MAX (1023) /* 2^10-1 */
+
+/* Used to store tile IDs. Stored in 10 bits; max value is 1023! */
 typedef u16 kf_tileid_t;
-/* Used to store connectivity variant. */
-typedef u16 kf_tiledatum_t;
+/* Used to store connectivity variant. Stored in 4 bits; max value is 15! */
+typedef u8 kf_tiledatum_t;
 
 
 struct kf_actor; /* Forward declaration */
 
 
-#define KF_TILEMASK_NORTH (0x0001)
-#define KF_TILEMASK_WEST  (0x0010)
-#define KF_TILEMASK_EAST  (0x0100)
-#define KF_TILEMASK_SOUTH (0x1000)
+#define KF_TILEMASK_NORTH (0b0001)
+#define KF_TILEMASK_WEST  (0b0010)
+#define KF_TILEMASK_EAST  (0b0100)
+#define KF_TILEMASK_SOUTH (0b1000)
 
 
 /* Represents a singular tile in the world. */
 struct kf_tile
 {
-	kf_tileid_t subid;
-	kf_tileid_t id;
-	kf_tiledatum_t data;
-};
+	kf_tileid_t subid   : KF_TILE_IDWIDTH;
+	kf_tileid_t id      : KF_TILE_IDWIDTH;
+	kf_tiledatum_t data : KF_TILE_DATAWIDTH;
+} __attribute__((packed));
 
 /* Represents a world (or a subworld, often called "rooms"). */
 struct kf_world
···
 size_t kf_world_getsize(struct kf_world *world);
 
 /* Get the sprite offset for a given tile datum. */
-struct kf_vec2(u32) kf_getspritefortilebitmask(kf_tiledatum_t t);
+struct kf_vec2(u32) kf_getspritefordatum(kf_tiledatum_t t);
 
 /* Update a tile and optionally its neighbours. */
 void kf_world_updatetile(struct kf_world *world, u32 x, u32 y, bool update_neighbours);

src/input.c

···
 	}
 	kf_inputbinds.count++;
 
-	kf_logdbg("add keybind: %d: %s (k=%d a=%d m=%d g=%d x=%d)", i, id, key, alt, mouse, gamepad, axis);
+	// kf_logdbg("add keybind: %d: %s (k=%d a=%d m=%d g=%d x=%d)", i, id, key, alt, mouse, gamepad, axis);
 	kf_inputbinds.id[i] = id;
 	kf_inputbinds.key[i] = key;
 	kf_inputbinds.alt[i] = alt;

src/main.c

···
 				selected_tile = t->id;
 
 			DrawRectangleLines(select.x * KF_TILE_SIZE_PX, select.y * KF_TILE_SIZE_PX, KF_TILE_SIZE_PX, KF_TILE_SIZE_PX, WHITE);
-			struct kf_vec2(u32) s = kf_getspritefortilebitmask(t->data);
-			DrawText(TextFormat("%d [0x%04x] (%d,%d) {%d,%d}", t->id, t->data, select.x, select.y, s.x, s.y), select.x * KF_TILE_SIZE_PX, select.y * KF_TILE_SIZE_PX - 10, 10, BLACK);
+			DrawText(TextFormat("%d [%d] (%d,%d)", t->id, t->data, select.x, select.y), select.x * KF_TILE_SIZE_PX, select.y * KF_TILE_SIZE_PX - 10, 10, BLACK);
 		}
 		player->draw(world, player);
 		EndMode2D();

src/world.c

···
 		w = x-1 >= world->width  ? 0 : kf_world_gettile(world, x-1, y)->id,
 		e = x+1 >= world->width  ? 0 : kf_world_gettile(world, x+1, y)->id,
 		s = y+1 >= world->height ? 0 : kf_world_gettile(world, x, y+1)->id;
-	t->data = 0x0000;
+	t->data = 0b0000;
 	if (t->id == n) t->data |= KF_TILEMASK_NORTH;
 	if (t->id == w) t->data |= KF_TILEMASK_WEST;
 	if (t->id == e) t->data |= KF_TILEMASK_EAST;
···
 }
 
 inline
-struct kf_vec2(u32) kf_getspritefortilebitmask(kf_tiledatum_t t)
+struct kf_vec2(u32) kf_getspritefordatum(kf_tiledatum_t t)
 {
-	switch (t)
-	{
-	case 0x0000: return (struct kf_vec2(u32)){0, 3}; /* 0x0000: */
-	case 0x0001: return (struct kf_vec2(u32)){0, 2}; /* 0x0001: N */
-	case 0x0010: return (struct kf_vec2(u32)){3, 3}; /* 0x0010: W */
-	case 0x0011: return (struct kf_vec2(u32)){3, 2}; /* 0x0011: NW */
-	case 0x0100: return (struct kf_vec2(u32)){1, 3}; /* 0x0100: E */
-	case 0x0101: return (struct kf_vec2(u32)){1, 2}; /* 0x0101: EN */
-	case 0x0110: return (struct kf_vec2(u32)){2, 3}; /* 0x0110: EW */
-	case 0x0111: return (struct kf_vec2(u32)){2, 2}; /* 0x0111: EWN */
-	case 0x1000: return (struct kf_vec2(u32)){0, 0}; /* 0x1000: S */
-	case 0x1001: return (struct kf_vec2(u32)){0, 1}; /* 0x1001: SN */
-	case 0x1010: return (struct kf_vec2(u32)){3, 0}; /* 0x1010: SW */
-	case 0x1011: return (struct kf_vec2(u32)){3, 1}; /* 0x1011: SWN */
-	case 0x1100: return (struct kf_vec2(u32)){1, 0}; /* 0x1100: SE */
-	case 0x1101: return (struct kf_vec2(u32)){1, 1}; /* 0x1101: SEN */
-	case 0x1110: return (struct kf_vec2(u32)){2, 0}; /* 0x1110: SEW */
-	case 0x1111: return (struct kf_vec2(u32)){2, 1}; /* 0x1111: NESW */
-	}
-	KF_UNREACHABLE("invalid bitmask: 0x%x", t);
-	return (struct kf_vec2(u32)){-1, -1};
+	static const
+	struct kf_vec2(u32) v[] = {
+		{0, 3}, /* 0b0000: */
+		{0, 2}, /* 0b0001: N */
+		{3, 3}, /* 0b0010: W */
+		{3, 2}, /* 0b0011: NW */
+		{1, 3}, /* 0b0100: E */
+		{1, 2}, /* 0b0101: EN */
+		{2, 3}, /* 0b0110: EW */
+		{2, 2}, /* 0b0111: EWN */
+		{0, 0}, /* 0b1000: S */
+		{0, 1}, /* 0b1001: SN */
+		{3, 0}, /* 0b1010: SW */
+		{3, 1}, /* 0b1011: SWN */
+		{1, 0}, /* 0b1100: SE */
+		{1, 1}, /* 0b1101: SEN */
+		{2, 0}, /* 0b1110: SEW */
+		{2, 1}, /* 0b1111: NESW */
+	};
+	return v[t];
 }
 
 struct kf_tile *kf_world_gettile(struct kf_world *world, u32 x, u32 y)
···
 		for (x = sx ; x < ex ; x++)
 		{
 			KF_SANITY_CHECK(tile->subid <= kf_tiles.count, "erroneous subtile on map at %u,%u: %u (count=%u)", x, y, tile->subid, kf_tiles.count);
-			/* 0x1111: full tile, no subtile rendering needed */
 			KF_SANITY_CHECK(tile->id <= kf_tiles.count, "erroneous tile on map at %u,%u: %u (count=%u)", x, y, tile->id, kf_tiles.count);
-			if ((tile->data != 0x1111 || kf_tiles.transparent[tile->id]) && tile->subid && tile->id)
+
+			/* 15: full tile, no subtile rendering needed (unless transparent) */
+			if ((tile->data != 15 || kf_tiles.transparent[tile->id]) && tile->subid && tile->id)
 			{
 				kf_drawsprite_wh(
 					kf_tiles.sheet[tile->subid],
···
 					kf_tiles.sprite[tile->subid].y + 1
 				);
 			}
+
 			if (tile->id)
 			{
-				struct kf_vec2(u32) s = kf_getspritefortilebitmask(tile->data);
+				struct kf_vec2(u32) s = kf_getspritefordatum(tile->data);
 				kf_drawsprite_wh(
 					kf_tiles.sheet[tile->id],
 					x*KF_TILE_SIZE_PX,
···
 					kf_tiles.sprite[tile->id].y + s.y
 				);
 			}
+
 			tile++; /* shift tile pointer to the right */
 		}
 		tile += down; /* shift tile pointer down */