They've done some really good reverse engineering on this project.

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Conformant OpenGL® ES 3.1 drivers are now available for M1- and M2-family GPUs. That means the drivers are compatible with any OpenGL ES 3.1 application.

Our reverse-engineered, free and open source graphics drivers are the world’s only conformant OpenGL ES 3.1 implementation for M1- and M2-family graphics hardware. That means our driver passed tens of thousands of tests to demonstrate correctness and is now recognized by the industry.

Why did we pursue standards conformance when the manufacturer did not? Above all, our commitment to quality. We want our users to know that they can depend on our Linux drivers. We want standard software to run without M1-specific hacks or porting.

 

[ comments | sourced from HackerNews ]

 

Excerpt:

Our reverse-engineered, free and open source graphics drivers are the world’s only conformant OpenGL ES 3.1 implementation for M1- and M2-family graphics hardware. That means our driver passed tens of thousands of tests to demonstrate correctness and is now recognized by the industry.

To become conformant, an “implementation” must pass the official conformance test suite, designed to verify every feature in the specification. The test results are submitted to Khronos, the standards body. After a 30-day review period, if no issues are found, the implementation becomes conformant.

Unlike ours, the manufacturer’s M1 drivers are unfortunately not conformant for any standard graphics API, whether Vulkan or OpenGL or OpenGL ES.

 

There is a discussion on Hacker News, but feel free to comment here as well.