My project #fnott (notification daemon) uses #nanosvg to render SVG icons.

I've always thought the rendered icons looked bad, compared to the ones rendered by librsvg. I chalked it up to nanosvg being "simple stupid" [sic].

Turns out /I'm/ stupid.

Nanosvg produces RGBA output that is NOT pre-multiplied.

But, pixman expects pre-multiplied color channels.

Blend a non-premultplied image as if it was pre-multiplied, and the result is, well, crap.

https://github.com/memononen/nanosvg