Rybags, on Sun Jul 3, 2011 12:33 PM, said:
Using Antic 4 has problems of it's own if turning on GTIA mode. Same deal with all of the non-hires modes.
You can't generate all the possible bit-patterns, so you lose out on some colours.
Antic generates bit pairs for the non hires modes:
00=PF0, 01=PF1, 10=PF2, 11=PF3
Since you can't mix PF2 and PF3 within a character cell, that limits what selections you have available.
In modes without PF3 you lose out even more.
Correct, you only get 14 possible color combinations, and only 9 of these can be displayed every character cell. As I recall, colors 11 and 14 are undisplayable. In addition, certain of your higher luminance values can only be displayed in inverse.
If you are using Graphics 10 in antic 4 you do get all the available 9 colors in graphics 10 due to the weird layout of the palette but again, not all of them are available in the same character cell. In fact inverse characters actually have one fewer color available.
A possible way to get around this is to store two display lists in memory, one antic 2 and one antic 4, and store both in the same page in memory (for example page 6). Store your page # (page 6) in location 561. When you turn on gtia mode you would also have the low byte of the display list pointer (at 560) point to your antic 2 display list, which would enable you to have the entire range of GTIA colors available. When you turn off gtia mode, location 560 points back to your antic 4 display list.
This is based on a method I used in my Super CIN / Super MIN modes which display 80 colors at antic 4 resolution, by flipping a character set, the GTIA, and the display list pointer every VBLANK.
Edited by Synthpopalooza, Sun Jul 3, 2011 2:45 PM.