Unlocking the Power of Render Pipelines

In VR, creating a believable and immersive world is essential for the user experience. To achieve this, it’s necessary to render high-quality graphics at a high frame rate to maintain immersion, and that’s where render pipelines come in!

A render pipeline is a set of instructions that dictate how the graphics in a Unity scene are processed and displayed to the user. There are several types of render pipelines, including the built-in render pipeline, as well as High Definition Render Pipeline (HDRP) and Universal Render Pipeline (URP).

Choosing the right render pipeline is crucial because it determines the quality and performance of your VR project. If your pipeline is inefficient or slow, it can lead to lower frame rates and decreased immersion, which can negatively impact the user experience.

Different render pipelines come with unique features and limitations, so it’s crucial to choose the pipeline that best suits...

Getting to know Unity’s Scriptable Render Pipeline

Unity’s Scriptable Render Pipeline (SRP) is a powerful tool that allows developers to create custom render pipelines tailored to their specific VR projects. It provides full control over the rendering process and can significantly improve performance and visual quality. We mentioned URP and HDRP previously. They are both built on top of SRP. Creating a custom render pipeline requires a deep understanding of graphics programming and is not a beginner-friendly task.

Here are the key features of Unity’s SRP:

• Customizability: Unity’s SRP allows developers to customize the rendering pipeline as they can create shaders and rendering algorithms. This level of customization allows for better optimization and performance.
• Improved performance: SRP is designed to help developers improve performance by allowing them to create customized and more efficient rendering solutions for their experiences. It...

Exporting our built-in render pipeline project

The built-in render pipeline is the default render pipeline in Unity. It is a simple and lightweight pipeline that provides basic support for 3D graphics and is suitable for most 2D and 3D games. It supports standard materials, forward and deferred rendering, and a limited set of post-processing effects. It also supports basic lighting and shadows, and a limited set of reflection and transparency features. We have done all of our projects in this render pipeline thus far, and that will continue in the remaining chapters, but here, we will cover how to take a project we created in the built-in render pipeline and export it to a project that is using either URP or HDRP. When we export the package, we will need to further configure the project to make it functional in the render pipeline of your choice, but this is the best option rather than converting the current project from a built-in pipeline into one that uses URP or HDRP. At the end...

Importing our package into Universal Render Pipeline

URP is more advanced than the built-in render pipeline as it provides increased performance and improved visual quality. It’s designed to be flexible, customizable, and easy to use. It uses the SRP API, which allows you to create custom render pipelines. URP supports standard materials, forward and deferred rendering, a wide range of post-processing effects, advanced lighting and shadows, and reflection and transparency features. Additionally, it provides GPU instancing and support for Shader Graph. It’s suitable for 2D and 3D games, and it’s a good choice for projects that require more advanced lighting and visual effects but don’t require the level of photorealism and cinematic-quality visual effects provided by HDRP. It’s also a good choice for projects that need a high degree of flexibility and customizability.

Figure 9.2 – Universal Render Pipeline 3D sample...

Importing our package into High Definition Render Pipeline

HDRP is the most advanced render pipeline provided by Unity as it provides photorealistic graphics and cinematic-quality visual effects. It’s designed for use in high-end PC and console games, as well as architectural visualization, film, and animation. HDRP supports PBR, advanced lighting and reflections, volumetric lighting and fog, advanced post-processing effects, and ray tracing.

Figure 9.9 – High Definition Render Pipeline 3D sample scene

In this section, we will create a new HDRP project based on the premade Unity project template that Unity provides and then import our BuiltInDemo package into the project. As mentioned earlier in this chapter, HDRP is meant for higher-end PC and console VR experiences. That doesn’t mean that developers cannot use lower-end devices for developing with HDRP, though. Also, most standalone headsets can be connected to PCs for playing more...

Enabling post-processing in URP and HDRP

Compared to the built-in render pipeline, where you need to install a post-processing package and attach various components and layers, enabling post-processing in URP and HDRP is fairly straightforward. There is nothing you need to download. However, there may be a difference in what post-processing effects will be available for URP and HDRP.

To enable post-processing in both URP and HDRP, go through the following steps:

1. In your scene, create a new Global Volume GO (right-click | Volume | Global Volume).
2. In the Global Volume component, create a new profile.
3. Select Add Override to choose what effect you wish to apply.

This is where URP and HDRP really shine because they allow you to create great effects with more fidelity and better performance than the built-in render pipeline.

In the next section, we will go over how to switch render pipelines for an existing project.

Converting render pipelines within a project

While it’s possible to convert a project from Unity’s built-in render pipeline into URP or HDRP, it’s generally better to create a new project and import the assets into it.

There are several reasons why this is the case:

• Compatibility issues: Converting a project from the built-in render pipeline into URP or HDRP can lead to compatibility issues as some assets may not be fully compatible with the new pipeline. This can lead to broken materials, lighting, or other issues that can be difficult to resolve.
• Inefficient assets: Assets created for the built-in pipeline may not be optimized for use with URP or HDRP, and may not take full advantage of the new pipeline’s features. Starting a new project and importing assets allows you to rework or replace assets to make them more efficient and optimized for the new pipeline.
• Workflow efficiency: Starting a new project and importing assets allows you...

Summary

Render pipelines are the backbone of creating stunning, high-performance VR experiences. Choosing the right pipeline is essential to achieve optimal performance and immersion in your project. In this chapter, we covered everything you need to know about render pipelines, from understanding their role in VR development to exploring and configuring both URP and HDRP. We also showed you how to enable post-processing and export your project to different pipelines. By mastering these topics, you can ensure your VR project is optimized for the best possible performance and quality, resulting in an immersive and engaging experience for your users.

But don’t stop here – in the next section of this book, we’ll be diving even deeper into creating immersive experiences with the skills we have developed thus far. We’ll be combining many of the concepts that were introduced in past chapters and applying them to more complex projects. You’ll learn how...