TeamHavocRacing wrote:jlv wrote: Made me think about the possibility that on an Amiga it would have been much faster for 3d polygon games to render to a copper list instead of a bitmap.
Yes, compared to PC games of the same title back then you'll see amazing differences in art and framerates that were astonishing! Something else different an Amiga had built-in was the delicious stereo soundtracks. I almost re-installed my Amiga emulator, but I found a Stunt Car Racer retro track first....
The Amiga did have filled polygons in hardware, but they worked by drawing into a bitmap. I believe that's what most Amiga games used at the time. What I mean with the copper list is you'd bypass the bitmap entirely. The copper had the capability to wait for the raster beam to hit specific pixel position after which you could write to any graphics register you want. So if you want a line from the 50'th pixel to the 250'th pixel, you could just wait for pixel 50 and then write the correct color to the background color register, then wait for pixel 250 and set it back. That should have been way faster than actually writing all 200 pixels. As an added bonus you'd get to use all 4096 colors since the colors aren't stored in the bitmap.
The idea is similar to some of the Atari 2600 "racing the beam" techniques, except the copper had more precise timing than the 6502 in the Atari. Too bad the Amiga is obsolete now. It'd be fun to actually implement and see how fast it goes.
