One-stop Visual Studio Code Extension to compile, debug and profile Amiga C/C++ programs compiled by the bundled gcc 12.2 with the bundled WinUAE/FS-UAE.
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Mask & Source channels are backwards in the template project when blitting the bob #89
The mask should be channel A and the source channel B for the blit of the bob, the template is doing the reverse.
This doesn't cause any noticeable effect onscreen in the demo because the bob is being drawn over a cleared background, but this is confusing for anyone looking at the code.
I've corrected the lines below in main.c, You can verify this is correct by looking at 6.4 in the Amiga Hardware Reference Manual.
custom->bltcon0 = 0xca | SRCA | SRCB | SRCC | DEST | ((x & 15) << ASHIFTSHIFT); // A = mask, B = source, C = background, D = destination
...
custom->bltapt = src + 32 / 8 * 1;
...
custom->bltbpt = src;
The mask should be channel A and the source channel B for the blit of the bob, the template is doing the reverse. This doesn't cause any noticeable effect onscreen in the demo because the bob is being drawn over a cleared background, but this is confusing for anyone looking at the code. I've corrected the lines below in main.c, You can verify this is correct by looking at 6.4 in the Amiga Hardware Reference Manual.