I've played with and implemented a range of area fill algorithms in the past. Optimized span-filling (dating back to the 1990's) works very well, is fast, buff

I've played with and implemented a range of area fill algorithms in the past. Optimized span-filling (dating back to the 1990's) works very well, is fast, buffer friendly and delivers great results. Subtleties surface when you have to consider filling around dithered edges and partially transparent elements. Fur stuff. https://en.wikipedia.org/wiki/Flood_fill https://en.wikipedia.org/wiki/Flood_fill