Once your layer stack heights are defined in the plugin panel, click Render 3D . A separate OpenGL window will open, allowing you to pan, tilt, zoom, and rotate your extruded layout in real-time. Advanced Tips for Optimizing Your 25D Visualization
Unlike a true 3D tool that renders complex 3D meshes, "2.5D" implies a layered, top-down view where, while objects appear to have height, the underlying structure is still based on 2D planes stacked vertically. It is exceptionally useful for verifying that vias are correctly connecting intended metal layers. Why Use the 2.5D View? klayout 25d view