I want full 32-bit color with alpha blending so that the sprites can overlay translucently over other images with partial visibility through the blended colors. I know that PortablE doesn't support that function yet but the author has been helpful with feature requests and bug reports in the past.
Hollywood has the ability to add mask or alpha channel to a brush, but supporting that in HollyPaint is too much work for ATM. It would require additional tools like an eraser.
Maybe you're lucky and PortablE will be extended.
Perhaps the new animation plugin I linked in my post will make undo-redo a possibility as well. All that would be needed would be the ability to add a frame to the start of an animation, remove multiple frames from the start of the animation (for the case of editing after an undo) and the ability to render frames asynchronously frontwards and backwards. Since the plugin can save animations, I would assume it can also be used to edit animations.
Well, I could implement undo/redo just with an array of brushes. Maybe I'm adding that feature already to v1.1 which I want to release next week.
