Doesn't work on M1 Mac in Chrome

[greggman]

Maybe I'm using it wrong. I added some timing, but, if I display the mips many are missing or wrong

https://jsgist.org/?src=197ae8c120785c358eed40416c6d9292

[JolifantoBambla]

Thanks for reporting!

I don't have access to a m1 mac unfortunately. Do you know if more than 6 storage texture bindings per compute stage are supported in that environment? Because for the first 6 mip levels all workgroups work only on data in workgroup memory but if more than 6 mip levels are created in a single pass, texture data for the 6th mip level is duplicated into an intermediate storage buffer. Data from that buffer is then again loaded into workgroup memory for the next (up to) 6 levels. (In the original SPD implementation mip level 6 is bound as read-write texture for that purpose but webgpu does not support that for most formats.) I was missing a storage barrier before loading the 6'th mip level data into workgroup memory. I guess that might have been the problem here.

I added the barrier in v3.0.0 - I hope that fixes it. If not, you could limit the maximum number of mip levels that can be generated per pass to 6 for now:

const spd = new WebGPUSinglePassDownsampler({ device, maxMipsPerPass: 6 });