Fix incorrect material map passing

Author: Sopiro

.gitignore

@@ -1,4 +1,5 @@
 build/
 .vscode/
 .vs/
-.idea/
+.idea/
+.clangd

cli/model_loader.cpp

@@ -36,7 +36,7 @@ static void LoadMaterials(
     Scene& scene,
     tinygltf::Model& model,
     const std::string& base_path,
-    std::vector<std::pair<const Material*, const SpectrumTexture*>> materials
+    std::vector<std::pair<const Material*, const SpectrumTexture*>>& materials
 )
 {
     for (int32 i = 0; i < int32(model.materials.size()); i++)

src/util/image.cpp

@@ -23,12 +23,17 @@ Image1 ReadImage1(
     int32 components_per_pixel;
     float* data = stbi_loadf(filename.string().c_str(), &width, &height, &components_per_pixel, STBI_rgb_alpha);
 
-    if (!data || channel < 0 || channel >= components_per_pixel)
+    if (!data)
     {
         std::cerr << "Failed to read image1: " << filename.string().c_str() << std::endl;
         return {};
     }
 
+    if (channel < 0 || channel >= components_per_pixel)
+    {
+        return {};
+    }
+
     constexpr int32 stride = STBI_rgb_alpha;
     Image1 image(width, height);