Poor Shader Performance in Web Only

[rosshardy]

Hi! I'm building a mobile app with Expo/React Native Skia and I am going crazy trying to figure out why my shader is performing so badly on web, but well in mobile. It is taking about 30 seconds to apply to a 1100x500 image in Expo browser preview on my powerful PC, but only about 2.5 seconds in the Expo Go App on my iPhone. Any suggestions?

On web, when I profile performance in the browser, I see a ton of CanvasKit WebAssembly functions running it appears in sequence on one CPU. GPU does not seem to be getting utilized, for an unknown reason. I have tried unrolling the shader and ensuring it's suited for optimization. Same thing happens in Chrome and Firefox.

Thanks for any suggestions. I hope I'm just missing something silly here...

[rosshardy]

I believe I was able to finally get this working with the help of Surface.MakeOffscreen.