Any one could explain the differences between "WebGL via Metal" vs. "WebGPU" on iOS?

[odieXin]

WebGPU was an experimental feature on iOS 11 and 12.
WebGL via Metal is the latest option with iOS 15 and Mac OS as well.
Can someone explain their differences? @milhidaka

[milhidaka]

The two are completely different.
WebGL via Metal exposes a WebGL interface to JavaScript applications; there is an overhead to convert WebGL instructions to native GPU instructions.
WebGPU, implemented in iOS 11, exposes a new interface for using the GPU. It is a thin wrapper for Metal and can achieve relatively high performance. Because Metal is an Apple-specific technology, it was not ported to other platforms. We don't know the exact reason, but WebGPU was removed in iOS15. Once the WebGPU standard is established as friendly to all platforms, we expect to see WebGPU implemented in iOS again.

[odieXin]

Thanks @milhidaka for the detailed explanation!