feat: fix scene loading that it loads from disk if not already loaded

destrum/src/Graphics/Caches/MaterialCache.cpp

@@ -7,6 +7,7 @@
 #include <algorithm>
 #include <string>
 #include <stdexcept>
+#include <utility>
 
 void MaterialCache::init(
     GfxDevice& gfxDevice,
@@ -26,9 +27,9 @@ void MaterialCache::init(
             materialDataBuffer.buffer,
             "material data");
 
-        Material placeholderMaterial{};
-        placeholderMaterial.name = "PLACEHOLDER_MATERIAL";
-        placeholderMaterial.diffuseTexture = defaultTextures.white;
+        Material placeholderMaterial = Material::SimpleColor(
+            glm::vec3{1.0f},
+            "PLACEHOLDER_MATERIAL");
 
         placeholderMaterialId = addMaterial(placeholderMaterial);
         gfxDevice.getMemoryManager().flushAllocation(materialDataBuffer);
@@ -104,9 +105,14 @@ MaterialID MaterialCache::addMaterial(Material material)
     // exact range after batching updates.
 
     const auto materialId = static_cast<MaterialID>(materials.size());
-    std::string key = material.name.empty()
-        ? "material:" + std::to_string(materialId)
-        : material.name;
+    std::string key;
+    if (!material.assetReference.empty()) {
+        key = material.assetReference.cacheKey();
+    } else {
+        key = material.name.empty()
+            ? "material:" + std::to_string(materialId)
+            : material.name;
+    }
     const std::string baseKey = key;
     std::size_t suffix = 1;
     while (std::find(materialKeys.begin(), materialKeys.end(), key) != materialKeys.end()) {
@@ -121,13 +127,17 @@ MaterialID MaterialCache::addMaterial(Material material)
 
 MaterialID MaterialCache::addSimpleTextureMaterial(ImageID textureID)
 {
-    Material material{};
-    material.name = "simple texture material";
+    Material material = Material::SimpleColor(
+        glm::vec3{1.0f},
+        "simple texture material");
     material.diffuseTexture = textureID;
-    material.metallicFactor = 0.0f;
-    material.roughnessFactor = 1.0f;
 
-    return addMaterial(material);
+    return addMaterial(std::move(material));
+}
+
+MaterialID MaterialCache::addSimpleColorMaterial(glm::vec3 color, std::string name)
+{
+    return addMaterial(Material::SimpleColor(std::move(color), std::move(name)));
 }
 
 const Material& MaterialCache::getMaterial(MaterialID id) const
@@ -149,6 +159,37 @@ std::optional<MaterialID> MaterialCache::findMaterialByKey(std::string_view key)
     return static_cast<MaterialID>(std::distance(materialKeys.begin(), it));
 }
 
+std::optional<MaterialID> MaterialCache::findMaterialByName(
+    std::string_view name,
+    std::string_view sourceReference) const
+{
+    std::optional<MaterialID> fallback;
+    for (MaterialID id = 0; id < materials.size(); ++id) {
+        const auto& material = materials[id];
+        if (material.name != name) {
+            continue;
+        }
+
+        if (sourceReference.empty()) {
+            return id;
+        }
+
+        if (!material.assetReference.empty() &&
+            material.assetReference.path == sourceReference) {
+            return id;
+        }
+
+        // A manually-created material may have the same name but no source
+        // reference. Keep it as a fallback for scenes saved before canonical
+        // file-backed material keys were introduced.
+        if (!fallback.has_value() && material.assetReference.empty()) {
+            fallback = id;
+        }
+    }
+
+    return fallback;
+}
+
 MaterialID MaterialCache::getFreeMaterialId() const
 {
     return static_cast<MaterialID>(materials.size());