reflectionRoughnessTexture property
The metallic-roughness texture the camera depth prepass samples so screen-space reflections have a per-pixel roughness (roughness in G), or null to use a fully-rough placeholder. The base material has none, so it reads as fully rough and receives no screen-space reflection; a lit material overrides this.
Implementation
@override
gpu.Texture? get reflectionRoughnessTexture =>
resolveTextureSource(metallicRoughnessTexture);