# PostProcessEffectContext An object RealityKit passes data to a post process effect method. ``` struct PostProcessEffectContext ``` ## Overview You can register a method that applies postprocessing effects to a scene RealityKit renders with a [`RealityView`](/documentation/RealityKit/RealityView). Once every frame, RealityKit calls that function before displaying the scene. You can use this to apply postprocess effects using any APIs that can modify an image texture. However, because RealityKit calls this method every frame, prioritize using APIs that execute on the GPU, such as Metal compute functions, , or . You can also render additional content on top of the frame buffer, such as a SpriteKit scene. > Note: For more information on implementing postprocess effects, see > , > which demonstrates multiple postprocess techniques. A postprocess method takes a single `PostProcessEffectContext` parameter, which contains data the callback method needs to modify the rendered scene, including the frame buffer, depth map, and a property for writing the image you modify. The postprocess method in your [`PostProcessEffect`](/documentation/RealityKit/PostProcessEffect) type needs to encode to the output texture, or the frame is never displayed. A postprocess method looks like this: ```swift func postProcess(context: borrowing PostProcessEffectContext) { // Handle postprocessing here. } ``` To register a method as the postprocess render callback, add an implementation for [`postProcess(context:)`](/documentation/RealityKit/PostProcessEffect/postProcess(context:)) in your type that conforms to [`PostProcessEffect`](/documentation/RealityKit/PostProcessEffect): ```swift class LaplacianPostProcess: PostProcessEffect { // Post process callback. func postProcess(context: borrowing PostProcessEffectContext) { let filter = MPSImageLaplacian() filter.encode(commandBuffer: context.commandBuffer, sourceTexture: context.sourceColorTexture, destinationTexture: context.compatibleTargetTexture) } } ``` To stop postprocessing, you can set the [`customPostProcessing`](/documentation/RealityKit/RealityViewRenderingEffects/customPostProcessing) property to [`none`](/documentation/RealityKit/RealityViewPostProcessEffect/none). ```swift content.renderingEffects.customPostProcessing = .none ``` If your app turns postprocessing on and off frequently, another option for disabling postprocess effects is to keep your callbacks registered, but use an to encode the unmodified frame buffer directly to the output texture whenever postprocess effects aren’t active. ```swift var isEnabled: Binding func postProcess(context: borrowing PostProcessEffectContext) { if isEnabled.wrappedValue { let filter = MPSImageLaplacian() filter.encode(commandBuffer: context.commandBuffer, sourceTexture: context.sourceColorTexture, destinationTexture: context.compatibleTargetTexture) } else { // Remove processing effects. let blitEncoder = context.commandBuffer.makeBlitCommandEncoder() blitEncoder?.copy(from: context.sourceColorTexture, to: context.targetColorTexture) blitEncoder?.endEncoding() } } ``` ## Topics ### Instance Properties [`var commandBuffer: CommandBuffer`](/documentation/RealityKit/PostProcessEffectContext/commandBuffer) The Metal command buffer for encoding the frame. [`var device: any MTLDevice`](/documentation/RealityKit/PostProcessEffectContext/device) The Metal device where the scene renders. [`var projection: float4x4`](/documentation/RealityKit/PostProcessEffectContext/projection) The projection matrix that renders the frame. [`var sourceColorTexture: any MTLTexture`](/documentation/RealityKit/PostProcessEffectContext/sourceColorTexture) The rendered frame buffer. [`var sourceDepthTexture: any MTLTexture`](/documentation/RealityKit/PostProcessEffectContext/sourceDepthTexture) The frame’s depth buffer. [`var targetColorTexture: any MTLTexture`](/documentation/RealityKit/PostProcessEffectContext/targetColorTexture) The output texture where the postprocess callback writes the modified frame buffer. [`var time: TimeInterval`](/documentation/RealityKit/PostProcessEffectContext/time) The scene’s elapsed time. --- 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)