I have a strange request, I think it will require a bit of background first:
I'm working on a game that uses nearest texture filtering instead of interpolating (like the textures look pixelated instead of blurry when viewed up close). Because of this, I don't have to worry about UV islands bleeding into each other as long as they are aligned on the pixel grid. I'm making the models quads only and all of the quads are fairly uniform in scale, so here's what I'd like to do for the UVs:
Each quad is to be unwrapped as a perfect square whose area is 1/2^n of the UV grid so that each quad contains a small grid of pixels. There should be no space between the islands.
I'll probably make the texture at a resolution where each quad gets a number of pixels equal to the maximum anisotropy filter otherwise the islands/quads will bleed into each other.
I found an addon that lets me unwrap grids of quads into aligned grids but it doesn't work if all the quads are separate (it just stacks them on top of each other). Any ideas?