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| author | Kartik K. Agaram <vc@akkartik.com> | 2021-07-13 17:00:55 -0700 |
|---|---|---|
| committer | Kartik K. Agaram <vc@akkartik.com> | 2021-07-13 17:00:55 -0700 |
| commit | 272432ce759dbfa2b886fa86af4ba08d0689b59d (patch) | |
| tree | 997998225cc57f57fdca9e4dea0173502ba85f6f | |
| parent | 62a2afe0d842534f00decb9e8e4c85cdbcf36bff (diff) | |
| download | mu-272432ce759dbfa2b886fa86af4ba08d0689b59d.tar.gz | |
get rid of our ugly rounding code
It turns out "truncating" the last 4 bits is actually more accurate, because it divides up the palette evenly. Before: 0-7 -> 0 8-0x17 -> 1 0x18-0x27 -> 2 ... 0xd8-0xe7 -> 0xe 0xe8-0xff -> 0xf The first interval is just 8 shades, and the final interval is 24 shades.
| -rw-r--r-- | img.mu | 9 |
1 files changed, 1 insertions, 8 deletions
diff --git a/img.mu b/img.mu index 73aea245..0d58fb0d 100644 --- a/img.mu +++ b/img.mu @@ -487,14 +487,7 @@ fn dither-pgm-unordered _src: (addr image), _dest: (addr image) { break-if-<= nearest-color <- copy 0xf0 } - # . round to nearest multiple of 0x10 - { - var tmp/ecx: int <- copy nearest-color - tmp <- and 0xf - compare tmp, 8 - break-if-< - nearest-color <- add 8 - } + # . truncate last 4 bits nearest-color <- and 0xf0 # error -= (nearest-color << 16) { |