This actually raises an interesting point I'd probably need to dig into, but if someone already knows at least part of the answer, it would help.
So it looks like this converter reads in data using the original timings, and spits out a letterboxed version of the screen data using VESA timings (based on my not-so-careful reading of the code). So if I wanted to make this more of a pass-through of the Mac timings and let an external upscaler deal with it, I wonder if it's possible to simply bridge HSYNC/VSYNC to the outputs, and feed the video input to the RGB lines as outputs? I could probably tweak the converter code to be more of a passthrough, and even probably minimize the buffers involved when in that mode, but I'm kinda curious if the analog signals are close enough in this case to just skip the conversion outright.
