The first step to render using BRG is to create an instance of BatchRendererGroup and initialize it with an implementation of OnPerformCulling.
The OnPerformCulling callback is the main entry point of BRG and Unity calls it whenever it culls visible objects. For information on the parameters it receives, see OnPerformCulling. Typically, there are two tasks that the OnPerformCulling callback needs to perform:
In simple implementations, you can do these tasks directly in the OnPerformCulling callback, but for high-performance implementations, it’s best practice to do most of this work in Burst jobs. The OnPerformCulling callback should return a JobHandle that completes after the jobs write the output into the BatchCullingOutput parameter. If your implementation doesn’t use jobs, you can return an empty JobHandle.
See the following code sample for an example of how to create a BatchRendererGroup object and initialize it with the most minimum OnPerformCulling callback that compiles.
using System;
using Unity.Collections;
using Unity.Collections.LowLevel.Unsafe;
using Unity.Jobs;
using UnityEngine;
using UnityEngine.Rendering;
public class SimpleBRGExample : MonoBehaviour
{
private BatchRendererGroup m_BRG;
private void Start()
{
m_BRG = new BatchRendererGroup(this.OnPerformCulling, IntPtr.Zero);
}
private void OnDisable()
{
m_BRG.Dispose();
}
public unsafe JobHandle OnPerformCulling(
BatchRendererGroup rendererGroup,
BatchCullingContext cullingContext,
BatchCullingOutput cullingOutput,
IntPtr userContext)
{
// This example doesn't use jobs, so it can return an empty JobHandle.
// Performance-sensitive applications should use Burst jobs to implement
// culling and draw command output. In this case, this function would return a
// handle here that completes when the Burst jobs finish.
return new JobHandle();
}
}
Before you use OnPerformCulling to create draw commands, you need to provide your BatchRendererGroup object any meshes you want it to draw, and any materials you want it to use. For more information, see the next topic, Registering meshes and materials.
Did you find this page useful? Please give it a rating:
Thanks for rating this page!
What kind of problem would you like to report?
Thanks for letting us know! This page has been marked for review based on your feedback.
If you have time, you can provide more information to help us fix the problem faster.
Provide more information
You've told us this page needs code samples. If you'd like to help us further, you could provide a code sample, or tell us about what kind of code sample you'd like to see:
You've told us there are code samples on this page which don't work. If you know how to fix it, or have something better we could use instead, please let us know:
You've told us there is information missing from this page. Please tell us more about what's missing:
You've told us there is incorrect information on this page. If you know what we should change to make it correct, please tell us:
You've told us this page has unclear or confusing information. Please tell us more about what you found unclear or confusing, or let us know how we could make it clearer:
You've told us there is a spelling or grammar error on this page. Please tell us what's wrong:
You've told us this page has a problem. Please tell us more about what's wrong:
Thank you for helping to make the Unity documentation better!
Your feedback has been submitted as a ticket for our documentation team to review.
We are not able to reply to every ticket submitted.