fix: replace runtime waitIdle calls with a deletion queue

destrum/src/Graphics/Caches/MaterialCache.cpp

@@ -1,4 +1,4 @@
-#include <../../include/destrum/Graphics/Caches/MaterialCache.h>
+#include <destrum/Graphics/Caches/MaterialCache.h>
 
 #include <destrum/Graphics/GfxDevice.h>
 #include <destrum/Graphics/Util.h>
@@ -19,7 +19,8 @@ void MaterialCache::init(
 
         materialDataBuffer = gfxDevice.createBuffer(
             MAX_MATERIALS * sizeof(MaterialData),
-            VK_BUFFER_USAGE_STORAGE_BUFFER_BIT | VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT,
+            VK_BUFFER_USAGE_STORAGE_BUFFER_BIT | VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT |
+                VK_BUFFER_USAGE_TRANSFER_DST_BIT,
             VMA_MEMORY_USAGE_CPU_TO_GPU);
 
         vkutil::addDebugLabel(
@@ -51,12 +52,6 @@ void MaterialCache::cleanup(GfxDevice& gfxDevice)
 
 MaterialID MaterialCache::addMaterial(Material material)
 {
-    if (!materials.empty() && device != nullptr) {
-        // The material buffer is shared by all in-flight frames. A newly
-        // appended entry may be written while an older frame is reading it.
-        device->waitIdle();
-    }
-
     MaterialData* data = static_cast<MaterialData*>(materialDataBuffer.info.pMappedData);
 
     const auto id = getFreeMaterialId();
@@ -67,17 +62,14 @@ MaterialID MaterialCache::addMaterial(Material material)
         throw std::runtime_error("MaterialCache material buffer is not mapped");
     }
 
+    // Safe without waiting: no frame in flight can reference an id that didn't exist yet.
+    // Changing an existing material goes through GameRenderer::updateMaterialGPU.
     data[id] = toMaterialData(material);
     device->getMemoryManager().flushAllocation(
         materialDataBuffer,
         static_cast<VkDeviceSize>(id) * sizeof(MaterialData),
         sizeof(MaterialData));
 
-    // The caller may update multiple materials in one frame; the range flush is
-    // cheap for coherent allocations and required for non-coherent memory.
-    // The cache does not own a device reference, so the renderer flushes the
-    // exact range after batching updates.
-
     const auto materialId = static_cast<MaterialID>(materials.size());
     std::string key;
     if (!material.assetReference.empty()) {
@@ -210,17 +202,8 @@ Material& MaterialCache::getMaterialMutable(MaterialID id)
     return materials.at(id);
 }
 
-void MaterialCache::updateMaterialGPU(MaterialID id)
+MaterialData MaterialCache::getMaterialData(MaterialID id) const
 {
     assert(id < materials.size());
-    assert(materialDataBuffer.info.pMappedData && "materialDataBuffer must be mapped");
-
-    MaterialData* data =
-        reinterpret_cast<MaterialData*>(materialDataBuffer.info.pMappedData);
-
-    data[id] = toMaterialData(materials[id]);
-    device->getMemoryManager().flushAllocation(
-        materialDataBuffer,
-        static_cast<VkDeviceSize>(id) * sizeof(MaterialData),
-        sizeof(MaterialData));
+    return toMaterialData(materials[id]);
 }