Add assimp-based mesh import

engine/src/Resources/Mesh/Mesh.cpp

@@ -11,6 +11,12 @@ void Mesh::Release() {
     m_vertexData.Clear();
     m_indexData.Clear();
     m_sections.Clear();
+    m_vertexCount = 0;
+    m_vertexStride = 0;
+    m_attributes = VertexAttribute::Position;
+    m_indexCount = 0;
+    m_use32BitIndex = false;
+    UpdateMemorySize();
     SetInvalid();
 }
 
@@ -21,9 +27,11 @@ void Mesh::SetVertexData(const void* data, size_t size, Core::uint32 vertexCount
     m_attributes = attributes;
     
     m_vertexData.Resize(size);
-    std::memcpy(m_vertexData.Data(), data, size);
-    
-    m_memorySize += size;
+    if (size > 0 && data != nullptr) {
+        std::memcpy(m_vertexData.Data(), data, size);
+    }
+
+    UpdateMemorySize();
 }
 
 void Mesh::SetIndexData(const void* data, size_t size, Core::uint32 indexCount, bool use32Bit) {
@@ -31,13 +39,22 @@ void Mesh::SetIndexData(const void* data, size_t size, Core::uint32 indexCount,
     m_use32BitIndex = use32Bit;
     
     m_indexData.Resize(size);
-    std::memcpy(m_indexData.Data(), data, size);
-    
-    m_memorySize += size;
+    if (size > 0 && data != nullptr) {
+        std::memcpy(m_indexData.Data(), data, size);
+    }
+
+    UpdateMemorySize();
 }
 
 void Mesh::AddSection(const MeshSection& section) {
     m_sections.PushBack(section);
+    UpdateMemorySize();
+}
+
+void Mesh::UpdateMemorySize() {
+    m_memorySize = m_vertexData.Size() +
+                   m_indexData.Size() +
+                   m_sections.Size() * sizeof(MeshSection);
 }
 
 } // namespace Resources