First Look At External HD Textures In Software
Screenshot.
I've found that compatibility with standard _luma textures will be a pain. It seems that standard _luma textures have lower dimensions, plus no alpha channel, and are rendered by overdrawing the opaque textures with additive blending in realtime.
This makes sense for hardware rendering, but it's a bad, bad approach for software rendering. It's much slower than the standard "color shading map with fullbright colors" (aka colormap) approach of the software renderer.
In the scene shown in this screenshot, I've manually adjusted (upscaled and alphamapped) the _luma textures of the top side of the boxes with GIMP to see how they would look using the colormap approach.
I'm not happy with the idea of having to implement an algorithm to convert the _luma textures like that, so manually editing the _luma textures may be required. Also, I'm not sure if support for non-power-of-two HD textures will be implemented, as that would require huge surface caches.