What's new in HDRP version 12 / Unity 2021.2

This page contains an overview of new features, improvements, and issues resolved in version 12 of the High Definition Render Pipeline (HDRP), embedded in Unity 2021.2.

Added

The following list of features are new to version 12 of the High Definition Render Pipeline (HDRP), as part of Unity 2021.2.

Tessellation support for ShaderGraph Master Stack

From HDRP 12.0, you can enable tessellation on any HDRP Master Stack. The option is in the Master Stack settings and adds two new inputs to the Vertex Block:

Tessellation Factor
World Displacement

For more information about tessellation, see the Tessellation documentation.

Custom Velocity support for ShaderGraph Master Stack

From HDRP 12.0, you can enable custom Velocity on any HDRP Master Stack. This option is in the Master Stack settings and adds one new input to the Vertex Block:

Velocity

You can use this Vertex Block to create an additional velocity for procedural geometry (for example, generated hair strands) and to get a correct motion vector value.

Cloud Layer System

HDRP 12.0 introduces a cloud system that you can control through the volume framework.

HDRP includes a Cloud Layer volume override which renders a cloud texture on top of the sky. For more information, see the Cloud Layer documentation.

For detailed steps on how to create custom clouds in your scene, see creating custom clouds.

Volumetric Clouds volume override

HDRP now includes a Volumetric Clouds volume override which allows you to precisely control the cloud coverage in your scene. These clouds receive realistic lighting from the sun and sky. For more information, see the Volumetric Clouds documentation.

Lens Flares

HDRP 12.0 includes a new Lens Flare system. You can attach a Lens Flare (SRP) component to any GameObject.

Some Lens Flare properties only appear when you attach a Lens Flare (SRP) component to a light. Each Lens Flare has optional multiple elements that you can control individually. HDRP also provides a new lens flare asset and a new lens flare component that you can attach to any GameObject.

HDRP includes a new Lens Flare sample that uses presets and Textures. You can see an example of the Textures included in this sample in the image below:

Light Anchor

From HDRP 12.0, HDRP includes a new Light Anchor component. You can attach this component to any light to control the light in Main Camera view.

Light List

HDRP version 2021.2 includes a new setting in ShaderConfig.cs called FPTLMaxLightCount. You can use this setting to set the maximum number of lights per tile on the GPU. To increase this value, you must generate a new Shader config project. For information on how to create a new Shader config project, see HDRP-Config-Package.

New upsampling methods

HDRP includes the following upsample methods you can use to male lower resolution images appear sharper:

For more information about upscaling methods in HDRP, see Dynamic Resolution.

Temporal Anti-Aliasing Upsampling

HDRP 12.0 introduces the Temporal Anti-Aliasing (TAA) Upscale filter in the Dynamic resolution system.

This method uses temporal integration to produce a sharp upscaled image without sacrificing visual quality at lower resolutions. This filter is compatible with any device supported by HDRP and uses the Temporal Anti-aliasing (TAA) step in the pipeline.

The image below displays the Temporal Anti-Aliasing (TAA) Upscale (A) next to the Catmull-Rom (B) upscaling method.

For more information, see Dynamic Resolution

A:TAA Upscale. B: Catmull-Rom.

NVIDIA’s Deep Learning Super Sampling

HDRP 12.0 includes production-ready integration and support for NVIDIA’s Deep Learning Super Sampling (DLSS) v2.2.

NVIDIA Deep Learning Super Sampling (DLSS) uses artificial intelligence to increase graphics performance and quality. You can use DLSS to:

run real-time ray traced worlds at high frame rates and resolutions.
Improve the performance and quality of rasterized graphics. This is particularly useful for virtual reality (VR) applications.
run applications at higher frame rates. This helps to remove disorientation, nausea, and other negative effects that occur at lower frame rates.

For more information, see the HDRP Guide on DLSS.

AMD’s FidelityFX Super Resolution

HDRP 12.0 includes production-ready integration and support of AMD’s FidelityFX Super Resolution. This upscale filter uses a spatial super-resolution method that balances quality and performance. For more information, see AMD FidelityFX.

This upscale filter has no dependencies and runs at the end of the post-processing pipeline.

The filter also runs when at 100% screen resolution, because it can have beneficial sharpening effects.

To enable AMD’s FidelityFX Super Resolution.:

Open the Project settings window (menu: Edit > Project settings).
Expand the Quality drop down and select HDRP.
Expand the Dynamic resolution section.
Open the Default Fallback Upscale Filter drop down .
Select FidelityFX Super Resolution.

Mip Bias Support

This HDRP version introduces a new setting called Use Mip Bias. This setting improves the detail of any upscaling filters you use in your scene.

To enable Use Mip Bias:

Open the Project settings window (menu: Edit > Project settings).
Expand the Quality drop down and select HDRP.
Expand the Dynamic resolution section.
Enable the Use Mip Bias checkbox.

ClearFlag

HDRP 2021.2 includes the new ClearFlag.Stencil function. Use this to clear all flags from a stencil.

From HDRP 2021.2, ClearFlag.Depth does not clear stencils.

Probe Volumes Global Illumination (Experimental)

HDRP 12.0 introduces an experimental version of the Probe Volume system that creates pre-computed probe-based global illumination. You can use this system to place light probes automatically and create per-pixel lighting.

The Probe Volume system supports volumetric fog. You can also use it to improve Screen Space Global Illumination results. This is an experimental release which is intended to gather feedback. This means it is not recommended for use in a production context.

In its current state, use the Probe Volume system as a replacement for the per-object Light Probe system, not as a replacement for lightmaps. This feature works best in a scene that uses large, static GameObjects.

Updated

HDRP Global Settings

In HDRP 12.x the Runtime Debug Display toggle is now in the HDRP Global Settings Asset instead of the HDRP Asset. This toggle uses the currently active HDRP Asset as the source.

Area Lights

The AxF shader and Fabric master stack now correctly support Area lights. Hair master stack supports Area Lights but with incorrect lighting models (GGX currently).

Density Volume (Local Volumetric Fog)

HDRP 12.0 introduces multiple improvements to Density Volumes (Local Volumetric Fog):

Density Volumes is now named Local Volumetric Fog. This new name removes confusion with Volumes and makes it clear that this feature creates a fog effect.
Local Volumetric Fog masks now support 3D RenderTextures as masks.
3D mask Textures now use all four RGBA channels. This allows volumetric fog to have different colors and density based on the 3D Texture.
You can now change the mask Texture size limit (32x32x32). To do this, use the new setting in the HDRP Asset Lighting > Volumetrics section, called Max Local Volumetric Fog Resolution. The upper limit for mask Textures is now 256x256x256. An information box below the Max Local Volumetric Fog Resolution field tells you how much memory Unity allocates to store these Textures. When you increase the resolution of the mask Texture, it doesn't always improve the quality of the volumetric fog. Instead, use this property to find a balance between the Volumetrics quality and the Local Volumetric Fog resolution.
There is a new field to change the falloff HDRP applied when it blends a volume using the Blend Distance property. You can choose the Linear setting, which is the default and previous technique, or the Exponential setting, which is more realistic.
The minimal value of the Fog Distance parameter is 0.05 instead of 1. You can use this value to create fog effects that appear more dense.

Dynamic Resolution Scale

This version of HDRP introduces multiple improvements to Dynamic Resolution Scaling:

The exposure and pixel to pixel quality now match between the software and hardware modes.
New API in DynamicResolutionHandler to handle multi camera rendering for hardware mode. This allows you to change Cameras and reset scaling for each Camera.
New API in DynamicResolutionHandler that you can use to set an upscale filter at runtime.
Removed the Bilinear and Lanczos upscale filters.

This version of HDRP also introduces multiple fixes to Dynamic Resolution Scaling. For details, see Fixed: Dynamic Resolution Scaling.

AOV API

From HDRP 12.0, The AOV API includes the following improvements:

You can now override the render buffer format that HDRP uses internally when you render AOVs. To do this, call aovRequest.SetOverrideRenderFormat(true);.
This version of HDRP provides a world space position output buffer (see DebugFullScreen.WorldSpacePosition).
The MaterialSharedProperty.Specular output now includes information for Materials that use the metallic workflow. To do this, the metallic parameter is now fresnel 0.

RendererList API

From 2021.2, HDRP includes an updated RendererList API in the UnityEngine.Rendering.RendererUtils namespace. This API performs fewer operations than the previous version of the RendererList API when it submits the RendererList for drawing. Use this new version to query if the list of visible objects is empty.

You can use the previous version of the API in the UnityEngine.Experimental.Rendering namespace for compatibility purposes but it is now deprecated.

When you enable the Dynamic Render Pass Culling option in the HDRP Global Settings, HDRP uses the RendererList API to skip certain drawing passes based on the type of GameObjects that are currently visible. For example, if HDRP doesn’t draw any GameObjects with distortion, HDRP skips the Render Graph passes that draw the distortion effect and their dependencies, like color pyramid generation.

Additional Properties

From HDRP 12.0, More Options is now named Additional Properties. You can now access these properties in a new way: The cogwheel that was present in component headers is now an entry in the contextual menu. When you enable Show Additional Properties, Unity highlights the background of each additional property for a few seconds to show you where they are.

You can also choose whether to hide or display

Additional Properties globally in the Core Render Pipeline settings (menu: Edit > Preferences > Core Render Pipeline). To do this, use the Additional Properties > Visibility ndrop down.

Path tracing improvements

HDRP’s path tracing now supports more materials:

Fabric: Cotton/wool and silk variants.
AxF: SVBRDF and car paint variants.
Stacklit.

The Unlit material has also been updated with support for shadow mattes.

In addition, the sky visible from camera rays now matches exactly the rasterized version, rather than relying on lower quality environment textures.

Top level menus

HDRP 12.0 includes changes to some top level menus. This is to make the top level menus more consistent between HDRP and the Universal Render Pipeline. The top level menus this change affects are:

Window
- HD Render Pipeline Wizard is now at Window > Rendering > HDRP Wizard
- Graphics Compositor is now at Window > Rendering > Graphics Compositor
Assets
- HDRP Shader Graphs are now in Assets > Create > Shader Graph > HDRP
- Custom FullScreen Pass is now at Assets > Create > Shader > HDRP Custom FullScreen Pass
- Custom Renderers Pass is now at Assets > Create > Shader > HDRP Custom Renderers Pass
- Post Process Pass is now at Assets > Create > Shader > HDRP Post Process
- High Definition Render Pipeline Asset is now at Assets > Create > Rendering > HDRP Asset
- Diffusion Profile is now at Assets > Create > Rendering > HDRP Diffusion Profile
- C# Custom Pass is now at Assets > Create > Rendering > HDRP C# Custom Pass
- C# Post Process Volume is now at Assets > Create > Rendering > HDRP C# Post Process Volume
GameObject
- Density Volume is now at GameObject > Rendering > Local Volumetric Fog
- Sky and Fog Volume is now at GameObject > Volume > Sky and Fog Global Volume

Decals

When you create a custom decal shader in HDRP 12.x, the accumulated normal value stored in the depth buffer represents the surface gradient instead of the tangent space normal. You can find an example of this implementation in DecalUtilities.hlsl.

Decal normal blending

From HDRP 12.0 you can use a new option in the HDRP Asset (Rendering > Decals > Additive Normal Blending) to additively blend decal normals with the GameObject's normal map.

In the image above, the example image on the left does not use this method. The image on the right uses the new additive normal blending method.

Increased the default GPU light count

This version of HDRP increases the default number of lights a single pixel can get influence from to 63. You can use a new setting in ShaderConfig.cs called FPTLMaxLightCount to set the maximum number of lights per tile on the GPU.

To increase this value, you must generate a new Shader config project. For information on how to create a new Shader config project, see HDRP-Config-Package.

Physical Camera

HDRP 12.0 includes the following physical Camera improvements:

You can now animate many physical Camera properties with keyframes using the Unity Timeline..
Added the Focus Distance property to the physical Camera properties. To improve compatibility with older HDRP versions, HDRP only includes this property in Depth of Field (DoF) computations if the Focus Distance Mode in the Depth of Field volume component is set to Camera.

Depth Of Field

Improved the quality of the physically-based Depth Of Field in the following ways:

Improved depth sorting to make the Depth Of Field result closer to the path-traced result.
Improved how HDRP handles near defocus blur and how it blends with in-focus areas.
Improved support for MSAA to remove artifacts around the edges of visible GameObjects.

Physically Based Hair Shader

HDRP 12.0 includes a new physically-based Marschner hair shader. You can use this as an alternative to the Kajiya-Kay hair shader. This new shading model allows you to quickly create a hair material that fits any lighting scenario. For more information about this new hair shader model and its parameters, see Hair Master Stack.

New shader for Custom Render Textures

This HDRP version includes a new shader that's formatted for Custom Render Textures in Assets > Create > Shader > Custom Render Texture. To use this shader, create a new Material and assign it to the Custom Render Texture's Material field.

Tessellation

HDRP 12.x improves motion vector support for tessellation in the following ways:

Updates the struct VaryingsPassToDS, so that it only manages the previousPositionRWS variable.
Adds the MotionVectorTessellation() function. For more information, see the MotionVectorVertexShaderCommon.hlsl file.
Evaluates the tessellationFactor in the vertex shader and passes it to the hull shader as an interpolator. For more information, see the VaryingMesh.hlsl and VertMesh.hlsl files.
Moves the GetTessellationFactors() function from LitDataMeshModification.hlsl to TessellationShare.hlsl. It calls a new function, GetTessellationFactor(), that's in the LitDataMeshModification.hlsl file.

Dynamic Render Pass Culling

HDRP 12.0 can dynamically cull rendering passes that don’t contribute to the output frame based on the viewpoint of the active Camera. For example, if there are no GameObjects that use low resolution transparency in the current viewpoint, HDRP can skip the composition pass for GameObjects that use low resolution transparency.

To enable this feature, go to Edit > Project Settings > HDRP Global HDRP Settings and enable Dynamic Render Pass Culling.

Built-in Object ID Custom Pass

HDRP 12.0 includes a built-in custom pass that you can use to generate Object IDs and display them as colors. To use this new custom pass, create a Custom Pass volume and select the new ObjectIDCustomPassfrom the list of available custom passes.

Specular Occlusion

HDRP 12.0 includes a more precise method to calculate specular occlusion based on Ambient Occlusion (AO) and Bent normals. This replaces the old method for all materials and shader graphs.

Ambient Occlusion and Specular Occlusion

In HDRP 12.x, the algorithm that calculates how ambient occlusion and specular occlusion contributes to direct lighting doesn’t use the multi-bounce contribution (GTAOMultiBounce). This gives a more accurate direct lighting result.

Screen Space Global Illumination

HDRP 12.0 improves the quality of the Screen Space Global Illumination (SSGI) in the following ways:

Added a new fallback mechanic when the ray marching fails to return an intersection point based on reflection probes and the sky probe.
Improved the denoiser HDRP uses to filter the SSGI signal.
Improved the performance of SSRI evaluation at half-resolution, and the performance of the denoiser.
Emissive properties work correctly by default and don't require SSGI flags.

SSGI off:

SSGI on:

Ray Traced Global Illumination

HDRP 12.0 includes the following new volume parameters for Ray Traced Global Illumination (RTGI):

Ray Miss
Last Bounce

These new parameters control the fallback method HDRP uses when RTGI interacts with the reflection probe, and the sky.

This HDRP version also improves the quality of the RTGI denoiser.Emissive properties work correctly by default and do not require Screen Space Global Illumination (SSGI) flags.

This version includes a new RTGI Tracing option called Mixed. Select this option to make RTGI use a combination of ray tracing and ray marching to calculate global illumination. Mixed tracing only works with RTGI when you set the RTGI Mode to Performance. For more information, see tracing modes.

Ray Traced Reflections

HDRP 12.0 includes the following new volume parameters for Ray Traced Reflections :

Ray Miss
Last Bounce

These new parameters control the fallback method HDRP uses when Ray Traced Reflections interact with the reflection probe, and the sky.

This version includes a new Ray Traced Reflections Mode option called Mixed Ray Casting. This new Mode is only a Select this mode to make Ray Traced Reflections evaluate ray intersections using ray marching and the GBuffer when possible.

This version includes a new Ray Traced Reflections Tracing option called Mixed. Select this option to make Ray Traced Reflections use a combination of ray tracing and ray marching to calculate global illumination. Mixed tracing for Ray Traced Reflections is only compatible with Lit shaders that use deferred rendering. For more information, see tracing modes.

Recursive rendering

HDRP 12.0 includes the following new volume parameters for Recursive Rendering:

Ray Miss
Last Bounce

These new parameters control the fallback method HDRP uses when Recursive Rendering interacts with the reflection probe, and the sky.

Conservative Depth Offset

HDRP version 12.0 adds a new Depth Offset property called Conservative to all Master stacks in HDRP. This option makes all depth offsets positive to take advantage of the early depth test mechanic.

The Conservative option only appears when you enable a Material’s Surface options > Depth Offset property.

Custom Pass Improvements

This version includes the following improvements to custom passes in HDRP:

Added a new API to override the camera properties: CustomPassUtils.OverrideCameraRendering.
You can now use CustomPassUtils Render functions to write directly into a RenderTexture instead of RTHandle.
Added a search field to filter custom passes to the custom pass volume component.
You can now use the C# API in the CustomPassContext to access the motion vector buffer.
Added a new Mode property to the custom pass volume component called Camera that you can use to render a custom pass on one specific Camera.
Added new nodes to ShaderGraph called Custom Color Buffer and Custom Depth Buffer. You can use these nodes to sample the custom color and depth buffers of custom passes.
Added a new injection point called AfterPostProcessBlurs that HDRP executes after the Depth of Field and Motion Blur injection points.

Custom Post Process

From HDRP 12.0 the custom post processes use the CommandBuffer.Blit function.

You can also use the new _CameraMotionVectorsTexture property to access the motion vectors buffer in a shader

To learn more about Custom Post Processes in HDRP, see the Custom Post Process.

Decal Performance Improvements

This version of HDRP introduces performance improvements for Decal Projectors:

Decal Projector’s processing and draw call creation now work in parallel and use burst.
Decal Projectors no longer require the LateUpdate method, which caused a performance bottleneck.
On an intel i9-8800KS CPU, the HDRP template took 0.378 ms to process all decals. The new changes improve this number to 0.025ms, which is a 15x improvement in performance. This number goes up the more decals are processed.
These improvements mean that HDRP is now dependant on the Burst 1.5 package for HDRP.

CPU Light Loop Performance Improvements

This version of HDRP introduces performance improvements for the CPU culling light loop. The new CPU light loop optimizations include:

Introduction of the new object HDLightEntityCollection - a master singleton object that keeps render side state of light objects.
Replacement of the flat ProcessVisibleLightsLoop with a parallel job using the HDVisibleLightEntities helper.
Burstification and parallelization of ProcessVisibleLights.
Introduction new sorting functions introduced in the core package.

For a more detailed information please check the Lightloop-Burstification documentation entry.

Removed

Receive SSGI flags

From HDRP 12.x, Materials don’t include the Receive SSGI flags property. This is because all Emissive materials are now compatible with Screen Space Global Illumination.

Fixed

Dynamic Resolution Scaling

This version of HDRP introduces multiple fixes to Dynamic Resolution Scaling:

The rendering artifact that caused black edges to appear on screen when in hardware mode no longer occurs.
The rendering artifacts that appeared when using the Lanczos filter in software mode no longer occur.
Fixed an issue that caused corrupted scaling on Dx12 hardware mode when a planar reflection probe or a secondary Camera is present.

Light list

HDRP 12.x splits the g_vLightListGlobal variable into g_vLightListTile and g_vLightListCluster. This fix corrects unexpected behavior on console platforms.

For a full list of changes and updates in version 12 of HDRP, see the changelog.