# Environment Radiance (RealityKit) Returns an environment’s diffuse and specular radiance value based on real-world environment, and an IBL map that is either a developer-provided map or a default map. ## Parameter Types |Input |Type | |------------|-------------| |`Base Color`|Color3| |`Roughness` |Half | |`Specular` |Half | |`Metallic` |Half | |`Normal` |Vector3f | |Output |Type | |-------------------|-------------| |`Diffuse Radiance` |Color3| |`Specular Radiance`|Color3| ## Parameter descriptions - `Base Color`: The base display color of the surface. The color under pure white light. - `Roughness`: The level of roughness of the surface. This value ranges between `0` and `1.0`, with `0` representing a perfectly specular surface and `1.0` representing maximum roughness. The default value is `0`. - `Specular`: The level of specular reflections that occur on the surface. - `Metallic`: The indicator if a surface is metallic or not. Set this value to `1` for metallic surfaces and `0` for nonmetallic surfaces. The default value is `0.0`. - `Normal`: The surface normal vector. The default value is `(0,0,0)`. ## Discussion: The Environment Radiance node has two outputs: - `Diffuse Radiance`: The diffuse radiance of the surface. Refers to light absorbed by the surface and then re-emitted in all directions. - `Specular Radiance`: The specular radiance of the surface. Refers to light reflected off of the surface. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)