# init(_:) Creates a custom base color object from an existing physically based material’s base color object. ``` init(_ value: PhysicallyBasedMaterial.BaseColor) ``` ## Parameters `value` The base color object from a physically based material. ## Discussion Use this initializer to create a [`CustomMaterial.BaseColor`](/documentation/RealityKit/CustomMaterial/BaseColor-swift.struct) that contains the same tint and texture values as an existing [`PhysicallyBasedMaterial.BaseColor`](/documentation/RealityKit/PhysicallyBasedMaterial/BaseColor-swift.struct) object. Both `tint` and `texture` from the [`PhysicallyBasedMaterial.BaseColor`](/documentation/RealityKit/PhysicallyBasedMaterial/BaseColor-swift.struct) object are available in your surface shader, but RealityKit doesn’t automatically use those values to render the entity. Your surface shader needs to calculate the final base color value for each pixel and assign it by calling `params.surface().set_base_color()`. For more information on creating custom materials and writing shader functions, see [Modifying RealityKit rendering using custom materials](/documentation/RealityKit/modifying-realitykit-rendering-using-custom-materials). --- 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)