Reduce Application Lag while using shadows in SceneKit

Question

I am working on a 3D map in SceneKit. When I enable the Cast Shadow Property of a directional light in SceneKit, the shadows appear, but the application becomes very slow.

How do I reduce the lag while still maintaining shadows in the scene?

Answer 1

Use Fake Shadows (shadows generated as a texture in 3D authoring or 2D authoring app) rather than True Shadow Map. To apply fake shadows as a texture for 3D plane use PNG file format with premultiplied alpha channel (RGB * A). It considerably reduces Processing and Memory Usage when using shadows in RealityKit or SceneKit.