Get tips for Unity 6 lighting, material, and environment updates in our latest HDRP e-book

Are you ready to create breathtaking environments and ultra-realistic lighting for your next game? Then don’t wait to download our latest e-book: Lighting and environments in the High Definition Pipeline (Unity 6 edition).

In Unity 6, the High Definition Render Pipeline (HDRP) delivers physically accurate lighting, high-fidelity materials, and cinematic effects to make your scenes more immersive.

Add depth to your scenes with volumetric fog and shadows. Make realistic-looking skies with Cloud Layers, and transition in real-time from day to night with Lighting Scenarios. Use the advanced water system to fill in the oceans and rivers, complete with waves, caustics, and foam. Make your landscapes come alive with SpeedTree’s dynamic vegetation, and use ray tracing to capture a new level of realism, from the soft sheen of brushed metal to the intricate dance of light through layered glass.

This guide is updated from the Unity 2022 LTS version. The main author of this version, as well as previous ones, is Wilmer Lin, a 3D and visual effects artist with over 15 years of industry experience in film and television, now working as an independent game developer and educator.

This latest edition covers all the capabilities included in HDRP in Unity 6 and 6.1. Use it together with HDRP documentation to get all the know-how and inspiration you need to create beautiful visuals in projects targeting high-end consoles and PCs.

Note: If you’re completely new to HDRP, check out the Unity Learn tutorial Getting started with the High Definition Render Pipeline.

The guide is designed to help you navigate HDRP’s extensive set of tools. You can jump directly to a topic of interest, whether it’s lighting, environment effects, rendering techniques, or optimization strategies.

While each chapter is standalone, note that many topics are interconnected. For example, HDRP’s lighting system spans multiple sections, covering physical light units, Volumes, and post-processing techniques.

Similarly, environment-related features like terrain, water, sky, and fog systems often work together to create immersive worlds. Try exploring related chapters together for a more complete understanding of HDRP’s capabilities.

Let's look at some of the additions to this new version of the guide.

Here are the highlights in the e-book for those moving from HDRP in 2022 LTS.

Lighting

LightBaker: HDRP’s new backend LightBaker v1.0 takes a “snapshot” of the Scene state when starting a bake instead of continuously checking for scene changes every frame. The bake runs uninterrupted unless manually canceled, reducing unnecessary recalculations and improving Editor performance.

Baking Profile: The Lighting window now provides a GPU Baking Profile for the GPU Lightmapper. This feature divides lightmaps into tiles, with presets optimizing for either faster baking or lower memory usage.

Adaptive Probe Volume (APV) updates: LightBaker now allows you to bake light probes and APVs independently from your lightmaps. APVs now also support sky occlusion baking, allowing GameObjects to adjust their lighting dynamically using the sky color from the ambient probe. This allows you to simulate a day-night cycle using APVs.

Ray tracing improvements: Ray tracing now includes new APIs to provide more control over ray-tracing acceleration structures.

Bicubic sampling for lightmaps: This feature can blur and smooth lightmaps, making them appear higher quality even at low-resolution. It’s beneficial for large environments that use baked lighting, where memory and performance constraints may require lower-resolution lightmaps.

Area light improvements: Area lights now use a “pillow” windowing function for range attenuation. This allows them to fade out more smoothly and work better with different material types while reducing CPU memory usage.

Path tracing improvements: Disc- and tube-shaped area lights are now supported with path tracing. Box lights have also been fixed to ensure correct illumination behavior. Additionally, volumetric fog controls have been added to area lights, allowing you to fine-tune their influence for more realistic atmospheric effects.

Environment effects

Planet parameters: A shared set of parameters in the Visual Environment override now affect various environment effects like volumetric clouds, fog and physically based sky.

Physically Based Sky Volume: The PBR Sky Volume has been optimized by removing some precomputation steps, allowing real-time sky updates with minimal performance impact. A new ozone layer has been added, improving sky color accuracy near the horizon for more realistic twilight effects.

Also, aerial perspective can now simulate light absorption by particles in the atmosphere when looking at distant objects, such as mountains or clouds.

Volumetric clouds: Clouds are no longer clipped by the far plane, and earth curvature control has been centralized in the Visual Environment settings.

Water system: The water system enhances support for GameObject transforms on water surfaces, including translation, rotation, and negative scaling. Unity 6.1 introduces a Water Decal target for Shader Graph to output foam and horizontal water deformations (like rolling waves).

Volumetric fog: Volumetric lighting performance has been optimized.

Performance optimizations

Dynamic resolution: Unity 6.1 introduces Spatial-Temporal Post-Processing (STP), a new, high-quality image upscaling technique that combines spatial upscaling (enhancing details from nearby pixels) with temporal upscaling (using previous frames to refine edges).

GPU Resident Drawer: The new GPU Resident Drawer leverages the Batch Render Group API for significant performance boosts when rendering complex scenes.

Variable Rate Shading (VRS): Variable Rate Shading (VRS) now supports Custom Passes, allowing dynamic shading resolution adjustments in specific screen areas to reduce GPU workload while maintaining visual quality.

Package Manager samples

The HDRP sample projects in the Package Manager have been reworked for consistency, with enhanced explanations and shared resources across pipelines:

Lit Material samples: All materials in this scene use the HDRP/Lit shader, demonstrating various material types (e.g., Standard, Subsurface Scattering, Anisotropy, etc.). Each sample highlights how HDRP handles realistic lighting over different surfaces.

Transparent Material samples: This scene demonstrates how HDRP handles transparency, including refractive materials, stacking transparent objects, and shadows from transparent materials. Switch between rasterization, ray tracing, and path tracing to explore the different rendering techniques.

Volumetric samples: This scene showcases volumetric fog, 3D textures, Shader Graph effects, and blending modes. The samples show how to recreate several fog effects, procedural noise, and smoke elements.

Environment samples: This island scene demonstrates several different cloud setups over an island terrain and ocean water system.

Water samples: This project includes a new water Cave sample scene. This scene features custom passes and volumetric fog sampling the water system caustics buffer to showcase advanced water rendering techniques. The Rolling Wave scene shows how to implement horizontal deformations, enabling effects like rolling waves.

Lens flares

In Unity 6, lens flares have been enhanced with several new features to improve visual fidelity and workflow:

Improved XR support: Lens flares now offer better compatibility with XR applications, ensuring consistent flare effects across various devices. 

Ring procedural shape: A new ring-shaped procedural flare allows you to create concentric circular flares, useful for bright light sources. 

Recursive Lens Flare assets: Lens flare assets can now be elements within other lens flares, enabling more complex and layered flare effects. 

Radial gradient support: Procedural shapes now support radial gradients, providing more natural-looking flares. 

Light override functionality: A new light override feature allows multiple flares to be influenced by a single light source. This streamlines setting up lens flare effects for multiple lights.

Hair and fur

The High-Quality Line Rendering Volume override now allows users to define hair width in centimeters per vertex, improving control and accuracy.

Below is an example of creating peach fuzz using a uniform width of 0.01 cm.

Additionally, a new screen coverage-based LOD mode dynamically culls hair strands based on viewport visibility. Artists can use an animation curve to control strand density, with the x-axis representing screen space coverage and the y-axis defining the percentage of strands rendered. This improves performance and visual quality.

We hope this guide inspires you to try HDRP for your next project.

You can find all of Unity’s e-books for experienced developers, artists, and technical artists in the Unity how-to hub and the best practices section in documentation.