Is there currently a way, in wasm/nanovg, to shift the render target to an image, draw to that image, and then later draw that image on the screen? I haven’t been able to figure out how to do this, but it should give me a massive improvement in draw time vs what I’m doing currently, which is to render everything as vectors every frame. If I could instead just render it as vectors once (or rather, add vectors to the image very slowly and infrequently) then just translate/rotate and draw the resulting image to the screen each frame, it would be vastly more efficient in my case.
Asobo has shown zero interest in fixing basic bugs to their rendering api(See: “GDIP SetClip still do not work properly”) for wasm much less improvements/extensions to the API.
I would suggest you look for workarounds to your problem such as pre-rendered bitmaps.