message: Remap texcoord indices in MaterialXView
  Remap unsupported texcoord indices in MaterialXView, allowing materials with multiple texcoords to be roughly visualized.
  Add exception handling to renderFrame in MaterialXView.
diff: @@ -121,6 +121,21 @@ void applyModifiers(mx::DocumentPtr doc, const DocumentModifiers& modifiers)
  }
  }
  }
  +
  + // Remap unsupported texture coordinate indices.
  + for (mx::ElementPtr elem : doc->traverseTree())
  + {
  + mx::NodePtr node = elem->asA<mx::Node>();
  + if (node && node->getCategory() == "texcoord")
  + {
  + mx::InputPtr index = node->getInput("index");
  + mx::ValuePtr value = index ? index->getValue() : nullptr;
  + if (value && value->isA<int>() && value->asA<int>() != 0)
  + {
  + index->setValue(0);
  + }
  + }
  + }
  }
  // ViewDir implementation for GLSL
  @@ -2108,7 +2123,17 @@ void Viewer::drawContents()
  }
  // Render the current frame.
  + try
  + {
  renderFrame();
  + }
  + catch (std::exception& e)
  + {
  + new ng::MessageDialog(this, ng::MessageDialog::Type::Warning,
  + "Failed to render frame: ", e.what());
  + _materialAssignments.clear();
  + glDisable(GL_FRAMEBUFFER_SRGB);
  + }
  // Capture the current frame.
  if (_captureRequested)
  