reset world2d shader and render_entity to prepare creating a demo for…

… shader command

assets/shaders/world2d.frag.glsl

@@ -2,8 +2,8 @@
 
 in vec2 vert_uv;
 
-layout(location=0) out vec4 col;
-layout(location=1) out uint id;
+layout(location = 0) out vec4 col;
+layout(location = 1) out uint id;
 
 uniform sampler2D tex;
 uniform uint u_id;
@@ -13,23 +13,30 @@ uniform vec4 tile_params;
 
 vec2 uv = vec2(
 	vert_uv.x * tile_params.z + tile_params.x,
-	vert_uv.y * tile_params.w + tile_params.y
-);
+	vert_uv.y *tile_params.w + tile_params.y);
 
 void main() {
 	vec4 tex_val = texture(tex, uv);
 	int alpha = int(round(tex_val.a * 255));
 	switch (alpha) {
-		case 0:
-			col = tex_val;
-			discard;
+	case 0:
+		col = tex_val;
+		discard;
 
-			// do not save the ID
-			return;
-		//@INSERT_COMMANDS@
-		default:
-			col = tex_val;
-			break;
+		// do not save the ID
+		return;
+	case 254:
+		col = vec4(1.0f, 0.0f, 0.0f, 1.0f);
+		break;
+	case 252:
+		col = vec4(0.0f, 1.0f, 0.0f, 1.0f);
+		break;
+	case 250:
+		col = vec4(0.0f, 0.0f, 1.0f, 1.0f);
+		break;
+	default:
+		col = tex_val;
+		break;
 	}
 	id = u_id;
-}
+}