refactor textures access

src/assets/assets_util.cpp

@@ -0,0 +1,24 @@
+#include "assets_util.hpp"
+
+#include "assets/Assets.hpp"
+#include "graphics/core/Atlas.hpp"
+#include "graphics/core/Texture.hpp"
+
+util::TextureRegion util::getTextureRegion(
+    const Assets& assets, const std::string& name, const std::string& fallback
+) {
+    size_t sep = name.find(':');
+    if (sep == std::string::npos) {
+        return {assets.get<Texture>(name), UVRegion(0,0,1,1)};
+    } else {
+        auto atlas = assets.get<Atlas>(name.substr(0, sep));
+        if (atlas) {
+            if (auto reg = atlas->getIf(name.substr(sep+1))) {
+                return {atlas->getTexture(), *reg};
+            } else if (!fallback.empty()){
+                return util::getTextureRegion(assets, fallback, "");
+            }
+        }
+    }
+    return {nullptr, UVRegion()};
+}

src/assets/assets_util.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <string>
+
+#include "maths/UVRegion.hpp"
+
+class Assets;
+class Texture;
+
+namespace util {
+    struct TextureRegion {
+        const Texture* texture;
+        UVRegion region;
+    };
+
+    TextureRegion getTextureRegion(
+        const Assets& assets,
+        const std::string& name,
+        const std::string& fallback
+    );
+}