Avoid redefining textures

src/model/mod.rs

@@ -420,7 +420,8 @@ impl Model {
     pub fn build_texture_for_material(&mut self, material: &Material, renderer: &Renderer) {
         if let Some(path) = material.textures.get("map_Kd") {
             let texture = renderer.make_texture(path);
-            self.textures.insert(path.to_owned(), Some(texture));
+            // Don't need to insert multiple times the same texture
+            self.textures.entry(path.to_owned()).or_insert(Some(texture));
         };
     }