Thanks!Stef wrote:Nice done, the image looks really nice !
I kinda suspected something like this had been attempted before, and last night I stumbled across a discussion of the Overdrive demo in which it became evident that it was doing something similar...Actually you used the "classical" scanline palette reprogramming but maybe at the maximum capabilities for the SNES.
But my demo wasn't at max capability. This afternoon I changed the preprocessing algorithm, from only checking the earliest scanline with a stale colour to using a two-constant quality weighting system on all scanlines with stale colours. (This boosted the execution time from 3-4 seconds to 30-40 seconds...) The result is attached - the first version had 337 colours; this one has 417. And it's still only using about 34% of the available HDMA bandwidth. I guess it's just a stubborn picture; the success of the HDMA scheduling seems to depend to a significant degree on the parameters used in the image quantizer...
I... guess so, yeah. I'd never seen that before.tepples wrote:So it's more like the 3200-color mode of DreamGrafix for Apple IIGS.
No, it was mentioned (by you, as a matter of fact), and AFAICT it should work. The problem is that it overloads the VRAM, so you have to letterbox it a bit.Mode 3 gives you a 256-color BG1 and a 16-color BG2, and 256-color layers can be set to "direct color" (a constant BBGGGRRR palette). This "direct color" alone nearly equals anything that can be done with the Genesis. But then you can do color addition between a direct color layer and a 16-color layer with a BBGR palette. Or did we already rule that out pages ago?