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In general, my engine is geared towards maximum data throughput to vram and audio ram.
I don't care one bit about ROM-size, because it's virtually unlimited nowadays.
If you run into any issues with that, please don't hesitate to get in touch.
I'd be happy to work with you to add some special features like expanded S-DD1 / SPC7110 mapping capabilities to support >48mbit games.
In particular, I'd really like to see an animated video running on the SNES. We definitely have the bandwidth to pull it off. The trick would be to use Mode3 + a tilemap to center the image, so all the tiledata is linear. Create a palette that is RGB332 (direct color mode sucks, low bits always clear, so whites look light gray.) Then use force blank and NBA swapping to toggle where the image data goes between the top half and bottom of half of RAM. That lets you span the transfer over two frames instead of one, which obviously halves the refresh rate. NTSC video runs at 30fps usually anyway.
There's even left-over RAM for subtitles, and the active display region can be used to spool voiced audio to the S-SMP.
I imagine it'll look roughly as good as the pre-MPEG Saturn movies. But on a much older, much slower system; where it's said to be "impossible."
Example:
@ 192x144
192*144=27648 bytes/frame
262-144=118 scanlines/vblank+forceblank period
118*(1364-40)=156232 cycles/frame
156232/8=19529 bytes/frame throughput
60->30fps conversion -> 19529*2 = 39058 bytes/frame
@ 208x156
208*156=32448
262-156=106
106*1324=140344
140344/8=17543
17543*2=35086
So let's say in the former case, we need 27648*30=829kbytes/second of ROM storage. If we throw in S-DD1 or SPC7110 real-time decompression, we can drop that by ~30% or so to ~600kb or less/second. Yeah, I know it's really painful. But with a custom bank swapping mapper, I don't see a reason we can't make a 64MB proof-of-concept video.
I've wanted to do this for a while, but I don't have the audio expertise. I was hoping someone would find the SNES CD player add-on for that one "Let's Learn English"-like game. Then I could emulate redbook through it. But I've never so much as seen a picture of one, not entirely sure it even exists, though it's technically pretty trivial. Connect to expansion bus, and stream the audio through the S-DSP mixer pins ...