I use pixelmator at the moment to do pixel art to make 8-bit-esque game sprites.
For iOS, alas, we need to spit out multiple versions of these. For example, I'm drawing the art at 19x19px (one pixel = one pixel in the drawing app for ease of drawing) but I actually need to then output this as:
38x38 76x76 108x108
Pixelmator has a major flaw in terms of producing pixel art in that you can't scale and resample an image using 'nearest neighbor' interpolation which would preserve the pixel look.
So...I need a better tool. Can anyone recommend a decent raster based illustration tool that can automatically scale up and output images using a preferred interpolation method?
Photoshop is an option...but we're hoping for a non-Adobe solution if it exists (and open source would be even better)