image quantization?

[Shadowblitz16]

Can we get utilities to import/export between rgba32 images, compressed indexed bitmaps and uncompressed 32 grayscale images.

• Rgba 32 for importing assets.
• Compressed indexed bitmaps for binary storage.
• And Uncompressed 32 Grayscale images for drawing with palette swapping.

Ideally the compressed indexed bitmaps should not store the palette, and not be padded.

Also compressed indexed bitmaps should support any range from 1bit to 256bits per pixel.

[Seldom-SE]

I'd accept a PR for asset processing from Rgba 32 to compressed binary blobs. I'm not sure where the grayscale images fit in. Would that need its own AssetLoader that PxSpriteLoader et al can use instead of ImageLoader? If so, PxSpriteLoaderSettings et al could accept some enum instead of ImageLoaderSettings so you can select your asset loader in the .meta file.

Related: when Bevy gets an editor, if it's sufficiently extensible, I'd like to make a little paint program in it specifically for seldom_pixel.