The size of the shadow map image that SceneKit renders when creating shadows.
Mac Catalyst 13.0+
SceneKit produces shadows by rendering the silhouettes of scene geometry into a 2D shadow map image and then projecting that image into the rendered scene. A larger shadow map image produces more detailed shadows at a higher cost to rendering performance; a smaller shadow map renders more quickly but results in pixelation at the edges of shadows.
The default value is CGSizeZero, specifying that SceneKit chooses a shadow map size automatically.