What’s new in URP 17.1 (Unity 6.1)

This section contains information about new features, improvements, and issues fixed in URP 17.1 (Unity 6.1).

For a complete list of changes made in URP 17.1, refer to the Changelog.

Features

This section contains the overview of the new features in this release.

Deferred+ rendering path

The Deferred+ rendering pathThe technique that a render pipeline uses to render graphics. Choosing a different rendering path affects how lighting and shading are calculated. Some rendering paths are more suited to different platforms and hardware than others. More info
See in Glossary is a deferred path with GPU Resident Drawer and GPU occlusion support. Similarly to the Deferred rendering path, Deferred+ is optimized for tiled-based mobile hardware architectures. The path is recommended for scenesA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary with a large number of lights and GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary instances.

Variable rate shading API

The variable rate shading (VRS) API lets you optimize shading performance of scriptable render passes and renderer features especially when your application is GPU-bound by pixelThe smallest unit in a computer image. Pixel size depends on your screen resolution. Pixel lighting is calculated at every screen pixel. More info
See in Glossary processing overhead.

VRS, also known as fragment shading rate, is a technique which lets you decouple the rasterizationThe process of generating an image by calculating pixels for each polygon or triangle in the geometry. This is an alternative to ray tracing.
See in Glossary and pixel shading rate. When setting a lower shading rate, the pixel shaderA program that runs on the GPU. More info
See in Glossary executes at a lower frequency, which can significantly improve GPU performance.

For more information and examples on how to use the VRSVirtual Reality More info
See in Glossary API in URP, refer to the following Unity Discussions post:

• Optimize Renderer Features with variable rate shading in Unity 6.1.

Improvements

This section contains the overview of the major improvements in this release.

Quality of life

This release implements the following quality of life improvements:

• Reduce build time using the new parameter k_UseDynamicBranchFogKeyword in the ShaderConfig.cs file in the Universal Render PipelineA series of operations that take the contents of a Scene, and displays them on a screen. Unity lets you choose from pre-built render pipelines, or write your own. More info
  See in Glossary Config package. The parameter lets you reduce the number of shader variants of fog keywords (FOG_EXP, FOG_EXP2, FOG_LINEAR) using dynamic branching. For more information, refer to Strip fog shader variants in URP

• Use the new property Probe Atlas Blending to turn the Reflection ProbeA rendering component that captures a spherical view of its surroundings in all directions, rather like a camera. The captured image is then stored as a Cubemap that can be used by objects with reflective materials. More info
  See in Glossary atlas on or off for Universal Render Pipeline Forward+ renderers, regardless of the blending settings. For more information, refer to the Probe Atlas Blending property description.

• Use new debug options for debugging custom passes when using Render Graph:

  • To isolate issues or investigate performance it is now possible to temporarily disable pass merging using the Disable Pass Merging setting in Rendering Debugger.

  • To debug arrays and mipmaps easier, there is now an array slice and mipmap info in the Render Graph Viewer.

  • To make it easier to catch invalid texture creation events, there is now an extra validation in the Render Graph texture descriptor.

Global Illumination

Added bicubic sampling support for lightmaps in HDRP and URP, which can significantly improve the appearance of low resolution lightmaps. To enable this option, go to Project Settings > Graphics > Use Bicubic Lightmap Sampling.

For more information, refer to Use Bicubic Lightmap Sampling.

Documentation

This release includes the following documentation improvements and additions:

• Custom lighting in URP.

  Implement custom lighting models to have more control over the visual style and achieve better performance.

Issues resolved

For a complete list of issues resolved in URP 17, refer to the Changelog.

What’s new in URP 17 (Unity 6)

This section contains information about new features, improvements, and issues fixed in URP 17.

For a complete list of changes made in URP 17, refer to the Changelog.

Features

This section contains the overview of the new features in this release.

Render graph system

In this release, Unity introduces the render graph system. The render graph system is a framework built on top of the Scriptable Render Pipeline (SRP) API. This system improves the way you customize and maintain the render pipeline.

The render graph system reduces the amount of memory URP uses and makes memory management more efficient. The render graph system only allocates resources the frame actually uses, and you no longer need to write complicated logic to handle resource allocation and account for rare worst-case scenarios. The render graph system also generates correct synchronization points between the compute and graphics queues, which reduces frame time.

The Render Graph Viewer lets you visualize how render passes use frame resources, and debug the rendering process.

For more information about the render graph system, refer to the render graph documentation.

Alpha Processing setting in post-processing

URP 17 adds an Alpha Processing setting (URP Asset > Post-processing > Alpha Processing). If you enable this setting, URP renders the post-processing output into a render texture with an alpha channel. In previous versions, URP discarded the alpha channel by replacing alpha values with 1.

The render target requires a format with the alpha channel. The camera color buffer format must be RGBA8 for SDR (HDR off) and RGBA16F for HDR (64-bits). You can configure the format using the settings in URP Asset > Quality.

Example use cases for this feature:

• Render in-game UI, such as a head-up display. You can render multiple render texturesA special type of Texture that is created and updated at runtime. To use them, first create a new Render Texture and designate one of your Cameras to render into it. Then you can use the Render Texture in a Material just like a regular Texture. More info
  See in Glossary with different post-processingA process that improves product visuals by applying filters and effects before the image appears on screen. You can use post-processing effects to simulate physical camera and film properties, for example Bloom and Depth of Field. More info post processing, postprocessing, postprocess
  See in Glossary configurations and compose the final output using the alpha channel.

• Render a character customization screen, where Unity renders a background interface and a 3D character with different post-processing effects and blends them using the alpha channel.

• XRAn umbrella term encompassing Virtual Reality (VR), Augmented Reality (AR) and Mixed Reality (MR) applications. Devices supporting these forms of interactive applications can be referred to as XR devices. More info
  See in Glossary applications that need to support video pass-through.

Reduce rendering work on the CPU

URP 17 contains new features that let you speed up the rendering process by moving certain tasks to the GPU and reducing the workload on the CPU.

GPU Resident Drawer

URP 17 includes a new rendering system called the GPU Resident Drawer.

This system automatically uses the BatchRendererGroup API to draw GameObjects with GPU instancing, which reduces the number of draw calls and frees CPU processing time.

For more information on the GPU Resident Drawer, refer to the section Reduce rendering work on the CPU.

GPU occlusion culling

When using GPU occlusion cullingA process that disables rendering GameObjects that are hidden (occluded) from the view of the camera. More info
See in Glossary, Unity uses the GPU instead of the CPU to exclude objects from rendering when they’re occluded behind other objects. Unity uses this information to speed up rendering in scenes that have a lot of occlusion.

For more information on GPU occlusion culling, refer to the section Reduce rendering work on the CPU.

Foveated rendering in the Forward+ Rendering Path

The Forward+ Rendering Path now supports foveated rendering.

Camera history API

This release contains the camera history API which lets you access per-camera history textures and use them in custom render passes. History textures are the color and depth textures that Unity rendered for each cameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
See in Glossary in previous frames.

You can use history textures for rendering algorithms that use frame data from one or multiple previous frames.

URP implements per-camera color and depth texture history and history access for custom render passes.

Mipmap Streaming section in the Rendering Debugger

The Rendering Debugger now contains a Mipmap Streaming section. This section lets you inspect the texture streaming activity.

Spatial Temporal Post-Processing (STP)

Spatial Temporal Post-Processing (STP) optimizes GPU performance and enhances visual quality by upscaling frames Unity renders at a lower resolution. STP works on desktop platforms, consoles, and mobile devices that support compute shaders.

To enable STP, in the active URP Asset, select Quality > Upscaling Filter > Spatial Temporal Post-Processing (STP).

Improvements

This section contains the overview of the major improvements in this release.

Adaptive Probe Volumes (APV)

This release contains the following improvements to Adaptive Probe Volumes:

• APV Lighting Scenario Blending.

• APV sky occlusion support.

• APV disk streaming.

Volume framework enhancements

This release comes with CPU performance optimizations of the volume framework on all platforms, especially mobile platforms. You can now set global volume default values and override them in quality settings.

8192 shadow texture resolution

The Shadow Resolution property now contains the 8192 option for the Main Light and Additional Lights.

Use the URP Config package to change render pipeline settings

The URP Config package lets you change certain render pipeline settings that are not available in the Editor interface.

For example, you can change the maximum number of visible lights.

The URP documentation has moved to the Unity Manual

The documentation for the Universal Render Pipeline in Unity 6 has moved from the URP documentation site to the main Unity Manual. We’ve restructured URP-specific and general graphics pages so they focus more on user outcomes. The purpose of this change is to improve the discoverability of the URP documentation and reader experience.

Links to pages on the separate URP site now redirect to the relocated pages in the main manual (or an equivalent).

The URP scripting API documentation remains on the separate website.

Issues resolved

For a complete list of issues resolved in URP 17, refer to the Changelog.

Known issues

For information on the known issues in URP 17, refer to the section Known issues.