# specular The specular highlight applied to the entity. ``` var specular: PhysicallyBasedMaterial.Specular { get set } ``` ## Discussion In Physically Based Rendering (PBR), specular highlights primarily come from the object’s [`roughness`](/documentation/RealityKit/PhysicallyBasedMaterial/roughness-swift.property) value. RealityKit automatically renders materials that have a low roughness value with specular highlights based on the environment lighting and the shape of the entity. As a result, for most materials, you won’t need to specify a `specular` value when using [`PhysicallyBasedMaterial`](/documentation/RealityKit/PhysicallyBasedMaterial). For some types of dielectric (nonmetallic) materials, like facet-cut glass or gems, PBR algorithms don’t create bright enough specular highlights using just roughness. To accurately simulate those types of materials, use the [`specular`](/documentation/RealityKit/PhysicallyBasedMaterial/specular-swift.property) property to specify additional specular for the entity. The following example demonstrates how to specify specular using a single value for the entire material: ```swift material.specular = .init(floatLiteral: 0.8) ``` This example shows how to specify specular using a UV-mapped image texture: ```swift if let specularResource = try? TextureResource.load(named:"entity_specular") { let specularMap = MaterialParameters.Texture(specularResource) material.specular = .init(texture: specularMap) } ``` --- 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)