Your plots appear blank because SageMath’s built-in 3D viewer often malfunctions. To fix this, simply include viewer='threejs' when calling show(), for example: show(W + S, viewer='threejs', figsize=8). Alternatively, you can save the plot as an HTML file using (W + S).save('plot3d.html', viewer='threejs') and then open it in any new version browser. If you’re working in Jupyter, run %display plot3d threejs before plotting to ensure the correct viewer is used. Additionally, if you’re running Sage locally, make sure the OpenGL libraries are installed on your system to avoid rendering issues.