Awesome

Unity_Indirect-Rendering-With-Compute-Shaders

GPU-Driven demo in Unity Fork from https://github.com/ellioman/Indirect-Rendering-With-Compute-Shaders, the version of witch is 4 May 2019. The project is perfect for GPU-Driven testing, but it is a pity that maintenance stopped long time ago. Respect to the author ellioman.

The following contents are from the original.

Indirect Rendering With Compute Shaders

An example of rendering numerous instances in Unity3D using Compute shaders for culling and LOD'ing and Graphics.DrawMeshInstancedIndirect to draw.

Generative

Features

Tested on Metal (Mac) and D3D11.
Quasirandom squences to place the instances
Draw things using Graphics.DrawMeshInstancedIndirect
GPU Sorting with Bitonic sorting
Compute shader: Frustum and shadow caster culling
Compute shader: Occlusion culling with HierarchicalZBuffer
Compute shader: Detail (Screen Size) Culling
Compute shader: LOD objects using the distance from camera to object
Simple shadow mode: Only use one shadow mesh for each instance type to lower setpass calls

Project Setup

"_Example.cs" script on the "Example" game object:
- Creates the instance data and sends it to the Indirect Renderer class.
"IndirectRenderer.cs" on the "MainCamera" game object:
- Is the main class in the project. It initializes all the buffers and compute shaders and then dispatches the compute shaders and draws the objects when Unity calls the PreCull() function.
"HiZBuffer.cs" script on the "OccluderCamera" game object:
- Creates a hierarchial Z-Buffer texture that contains the depth texture and shadow map which are used when doing frustum and occlusion culling

TODO

Add reprojection of last frame’s depth to the Hi-Z (See "GPU-Driven Rendering Pipelines" below)
Improve the instance sorting:
- On my Macbook pro (mid 2014) sorting takes approx 50% of the GPU time
- The GPU sorting must support instance numbers that are not in the non power of two
- Find a better performant approach for the CPU Sorting
Create the Hi-Z Texture with compute shaders
Try out Raster Occlusion instead of Hi-Z (See "NVidia Siggraph 2014" & "Github - nvpro-samples" below)