Fix uninitialized UVs, missing CUDA_CHECK in cleanup, face-skip warning, and unused alias

scripts/generate_uv_models.py

@@ -51,7 +51,7 @@ def write_obj(path, name, vertices, uvs, normals, faces, mtl_lib, mtl_name):
 
 def gen_plane(filepath, size=4.0, subdivs=5, mtl_name='textured'):
     verts, uvs, norms, faces = [], [], [], []
-    N = normal = (0, 1, 0)
+    normal = (0, 1, 0)
 
     # Grid of (subdivs+1) x (subdivs+1) vertices
     def idx(ix, iz):
@@ -63,7 +63,7 @@ def idx(ix, iz):
             z = -size / 2 + iz * size / subdivs
             verts.append((x, 0.0, z))
             uvs.append((ix / subdivs, iz / subdivs))
-            norms.append(N)
+            norms.append(normal)
 
     # Two triangles per cell
     for ix in range(subdivs):

src/rayon/gpu_renderers/scene_builder_cuda.cu

@@ -133,13 +133,22 @@ static CudaScene::Geometry convertGeometry(const GeometryDesc &desc)
                                  static_cast<float>(desc.data.triangle.n2.y()),
                                  static_cast<float>(desc.data.triangle.n2.z()));
       geom.data.triangle.has_normals = desc.data.triangle.has_normals;
-      // UV coordinates
-      geom.data.triangle.uv0 = f2(static_cast<float>(desc.data.triangle.uv0.x()),
-                                  static_cast<float>(desc.data.triangle.uv0.y()));
-      geom.data.triangle.uv1 = f2(static_cast<float>(desc.data.triangle.uv1.x()),
-                                  static_cast<float>(desc.data.triangle.uv1.y()));
-      geom.data.triangle.uv2 = f2(static_cast<float>(desc.data.triangle.uv2.x()),
-                                  static_cast<float>(desc.data.triangle.uv2.y()));
+      // UV coordinates — only copy valid data; zero-initialize when UVs are absent
+      if (desc.data.triangle.has_uvs)
+      {
+         geom.data.triangle.uv0 = f2(static_cast<float>(desc.data.triangle.uv0.x()),
+                                     static_cast<float>(desc.data.triangle.uv0.y()));
+         geom.data.triangle.uv1 = f2(static_cast<float>(desc.data.triangle.uv1.x()),
+                                     static_cast<float>(desc.data.triangle.uv1.y()));
+         geom.data.triangle.uv2 = f2(static_cast<float>(desc.data.triangle.uv2.x()),
+                                     static_cast<float>(desc.data.triangle.uv2.y()));
+      }
+      else
+      {
+         geom.data.triangle.uv0 = f2(0.0f, 0.0f);
+         geom.data.triangle.uv1 = f2(0.0f, 0.0f);
+         geom.data.triangle.uv2 = f2(0.0f, 0.0f);
+      }
       geom.data.triangle.has_uvs = desc.data.triangle.has_uvs;
       break;
 
@@ -404,21 +413,21 @@ void CudaSceneBuilder::freeGPUScene(CudaScene::Scene *d_scene)
    if (host_scene.d_textures && host_scene.num_textures > 0)
    {
       std::vector<cudaTextureObject_t> host_tex(static_cast<size_t>(host_scene.num_textures));
-      cudaMemcpy(host_tex.data(), host_scene.d_textures,
-                 host_scene.num_textures * sizeof(cudaTextureObject_t),
-                 cudaMemcpyDeviceToHost);
+      CUDA_CHECK(cudaMemcpy(host_tex.data(), host_scene.d_textures,
+                            host_scene.num_textures * sizeof(cudaTextureObject_t),
+                            cudaMemcpyDeviceToHost));
       for (int i = 0; i < host_scene.num_textures; ++i)
       {
          if (host_tex[i])
          {
             cudaResourceDesc rd = {};
-            cudaGetTextureObjectResourceDesc(&rd, host_tex[i]);
-            cudaDestroyTextureObject(host_tex[i]);
+            CUDA_CHECK(cudaGetTextureObjectResourceDesc(&rd, host_tex[i]));
+            CUDA_CHECK(cudaDestroyTextureObject(host_tex[i]));
             if (rd.resType == cudaResourceTypeArray && rd.res.array.array)
-               cudaFreeArray(rd.res.array.array);
+               CUDA_CHECK(cudaFreeArray(rd.res.array.array));
          }
       }
-      cudaFree(host_scene.d_textures);
+      CUDA_CHECK(cudaFree(host_scene.d_textures));
    }
 
    // Free the scene struct itself (now on device)

src/rayon/scenes/obj_loader.hpp

@@ -34,7 +34,7 @@ class OBJLoader
     * The caller-supplied @p fallback_mat_id is used only for faces that
     * belong to a group with no usemtl directive (or when no .mtl is found).
     * Pass -1 for @p fallback_mat_id to require all materials to come from
-    * the .mtl file (faces without usemtl are then skipped with a warning).
+    * the .mtl file (faces without usemtl are then skipped with a one-time warning).
     *
     * @param filename         Path to .obj file
     * @param scene            Scene to add triangles to
@@ -70,6 +70,7 @@ class OBJLoader
       std::map<std::string, int> mtl_name_to_scene_id;
 
       int active_mat_id = fallback_mat_id; // Current material for faces
+      bool face_skip_warned = false;       // One-time warning when faces are skipped without a material
 
       auto resolveMtlMaterial = [&](const std::string &name) -> int {
          auto cached = mtl_name_to_scene_id.find(name);
@@ -167,7 +168,12 @@ class OBJLoader
          {
             if (active_mat_id < 0)
             {
-               // No material yet and no fallback — skip
+               // No material yet and no fallback — skip with a one-time warning per file
+               if (!face_skip_warned)
+               {
+                  std::cerr << "OBJ Loader: face(s) skipped — no 'usemtl' encountered and no fallback material provided\n";
+                  face_skip_warned = true;
+               }
                continue;
             }
 

src/rayon/scenes/scene_description.hpp

@@ -607,6 +607,9 @@ class SceneDescription {
         geom.data.triangle.v2 = v2;
         geom.data.triangle.has_normals = false;
         geom.data.triangle.has_uvs = false;
+        geom.data.triangle.uv0 = Vec3(0, 0, 0);
+        geom.data.triangle.uv1 = Vec3(0, 0, 0);
+        geom.data.triangle.uv2 = Vec3(0, 0, 0);
 
         // Compute bounding box with epsilon padding to avoid zero-thickness AABBs
         constexpr double eps = 1e-4;
@@ -637,6 +640,9 @@ class SceneDescription {
         geom.data.triangle.n2 = n2;
         geom.data.triangle.has_normals = true;
         geom.data.triangle.has_uvs = false;
+        geom.data.triangle.uv0 = Vec3(0, 0, 0);
+        geom.data.triangle.uv1 = Vec3(0, 0, 0);
+        geom.data.triangle.uv2 = Vec3(0, 0, 0);
 
         // Compute bounding box with epsilon padding to avoid zero-thickness AABBs
         constexpr double eps = 1e-4;