feat: enhance material creation to ensure Principled BSDF node exists and apply materials to exported objects

tools/blender_export_primitives.py

@@ -1,5 +1,6 @@
 import bpy
 import os
+import traceback
 
 # Clear existing objects
 bpy.ops.object.select_all(action='SELECT')
@@ -11,6 +12,7 @@ os.makedirs(output_dir, exist_ok=True)
 
 def create_material(name, base_color):
     """Create a PBR material with the specified base color (RGBA)"""
+    try:
         mat = bpy.data.materials.new(name=name)
         mat.use_nodes = True
         nodes = mat.node_tree.nodes
@@ -31,8 +33,14 @@ def create_material(name, base_color):
         bsdf.inputs['Roughness'].default_value = 0.5
         bsdf.inputs['Metallic'].default_value = 0.1
         
+        print(f"  Created material '{name}' with color {base_color}")
         return mat
+    except Exception as e:
+        print(f"ERROR creating material: {e}")
+        traceback.print_exc()
+        return None
 
+try:
     print("Creating GREEN sphere...")
     # Create and export UV Sphere with GREEN material
     bpy.ops.mesh.primitive_uv_sphere_add(segments=32, ring_count=16, radius=0.5, location=(0, 0, 0))
@@ -41,18 +49,26 @@ sphere.name = "Sphere"
     sphere.select_set(True)
     bpy.context.view_layer.objects.active = sphere
     bpy.ops.object.shade_smooth()
+    
     # Apply green material
     green_mat = create_material("SphereMaterial", (0.2, 1.0, 0.2, 1.0))  # Green
+    if green_mat:
         sphere.data.materials.append(green_mat)
+    
     sphere_path = os.path.join(output_dir, "sphere.glb")
+    print(f"  Exporting to {sphere_path}...")
     bpy.ops.export_scene.gltf(
         filepath=sphere_path,
         export_format='GLB',
         use_selection=True
     )
-print(f"✓ Exported sphere.glb (GREEN) to {sphere_path}")
+    print(f"✓ Exported sphere.glb (GREEN)")
+except Exception as e:
+    print(f"ERROR with sphere: {e}")
+    traceback.print_exc()
 
-print("Creating RED cube...")
+try:
+    print("\nCreating RED cube...")
     # Delete sphere and create cube with RED material
     bpy.ops.object.delete(use_global=False)
     bpy.ops.mesh.primitive_cube_add(size=1.0, location=(0, 0, 0))
@@ -61,18 +77,26 @@ cube.name = "Cube"
     cube.select_set(True)
     bpy.context.view_layer.objects.active = cube
     bpy.ops.object.shade_smooth()
+    
     # Apply red material
     red_mat = create_material("CubeMaterial", (1.0, 0.2, 0.2, 1.0))  # Red
+    if red_mat:
         cube.data.materials.append(red_mat)
+    
     cube_path = os.path.join(output_dir, "cube.glb")
+    print(f"  Exporting to {cube_path}...")
     bpy.ops.export_scene.gltf(
         filepath=cube_path,
         export_format='GLB',
         use_selection=True
     )
-print(f"✓ Exported cube.glb (RED) to {cube_path}")
+    print(f"✓ Exported cube.glb (RED)")
+except Exception as e:
+    print(f"ERROR with cube: {e}")
+    traceback.print_exc()
 
-print("Creating BLUE icosphere...")
+try:
+    print("\nCreating BLUE icosphere...")
     # Delete cube and create ico sphere for the "model" placeholder with BLUE material
     bpy.ops.object.delete(use_global=False)
     bpy.ops.mesh.primitive_ico_sphere_add(subdivisions=2, radius=0.5, location=(0, 0, 0))
@@ -81,21 +105,29 @@ ico.name = "IcoSphere"
     ico.select_set(True)
     bpy.context.view_layer.objects.active = ico
     bpy.ops.object.shade_smooth()
+    
     # Apply blue material
     blue_mat = create_material("IcoSphereMaterial", (0.2, 0.2, 1.0, 1.0))  # Blue
+    if blue_mat:
         ico.data.materials.append(blue_mat)
+    
     model_path = os.path.join(output_dir, "model.glb")
+    print(f"  Exporting to {model_path}...")
     bpy.ops.export_scene.gltf(
         filepath=model_path,
         export_format='GLB',
         use_selection=True
     )
-print(f"✓ Exported model.glb (BLUE) to {model_path}")
+    print(f"✓ Exported model.glb (BLUE)")
+except Exception as e:
+    print(f"ERROR with icosphere: {e}")
+    traceback.print_exc()
 
 print("\n" + "="*60)
-print("✓ ALL PRIMITIVE MODELS WITH COLORS EXPORTED SUCCESSFULLY!")
+print("✓ EXPORT COMPLETE!")
 print("="*60)
-print(f"  RED Cube:       {os.path.join(output_dir, 'cube.glb')}")
+print(f"Output directory: {output_dir}")
-print(f"  GREEN Sphere:   {os.path.join(output_dir, 'sphere.glb')}")  
+print("  - cube.glb (RED)")
-print(f"  BLUE IcoSphere: {os.path.join(output_dir, 'model.glb')}")
+print("  - sphere.glb (GREEN)")  
+print("  - model.glb (BLUE)")
 print("="*60)