Fastest way to read pixels in OpenGL?

Unity Engine
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1

Hey, I am trying to transfer the content of a RenderTexture to a Texture2D (or any other Container which I can encode into a JPG) and I am trying to avoid Texture2D.ReadPixels(…) due to performance reasons. I am developing for the Oculus Quest which works on OpenGL which means that I cannot use AsyncGPUReadback because it is not supported on OpenGL.

I have found this GitHub - Alabate/AsyncGPUReadbackPlugin: Unity plugin that provide AsyncGPUReadback for OpenGL which supports something equivalent to the unity AsyncGPUReadback on OpenGL via a Plugin, but sadly it states that it only works on Linux and I haven’t yet got it to work on my Windows PC due to an entryPointNotFoundException. That is especially sad since it basicly provides me with all the source code needed to solve the problem, but identifying and changing all necessary OS operations and building a working dll out it is out of my league.

Does anyone have a faster way (or any other way) to read the content of a RenderTexture than by calling Texture2D.ReadPixels(…)? A few frames Latency would be no problem at all.

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glReadPixels from a RenderTexture - Questions & Answers - Unity Discussions I suggest you start here

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Thank you, I will take a look into this later. I am currently following the route of using Vulkan where AsyncGPUReadback is supported.