diff options
| -rw-r--r-- | img.mu | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/img.mu b/img.mu index 6b37a3d9..1cf57567 100644 --- a/img.mu +++ b/img.mu @@ -27,8 +27,8 @@ fn main screen: (addr screen), keyboard: (addr keyboard), data-disk: (addr disk) var img-storage: image var img/esi: (addr image) <- address img-storage load-image img, data-disk -#? render-image screen, img, 0/x, 0/y, 0x300/width, 0x300/height - render-image screen, img, 0x20/x, 0x80/y, 0x258/width=600, 0x190/height=400 + render-image screen, img, 0/x, 0/y, 0x300/width, 0x300/height +#? render-image screen, img, 0x20/x, 0x80/y, 0x258/width=600, 0x190/height=400 #? render-image screen, img, 0x20/x, 0x80/y, 0x12c/width=300, 0xc8/height=200 #? render-pgm-image screen, img, 0x220/x, 0x80/y, 0x12c/width=300, 0xc8/height=200 } @@ -455,6 +455,12 @@ fn dither-pgm-unordered _src: (addr image), _dest: (addr image) { var dest-height-a/ecx: (addr int) <- get dest, height copy-to *dest-height-a, tmp } + # compute scaling factor 255/max + var target-scale/eax: int <- copy 0xff + var scale-f/xmm7: float <- convert target-scale + var src-max-a/eax: (addr int) <- get src, max + var tmp-f/xmm0: float <- convert *src-max-a + scale-f <- divide tmp-f # transform 'data' var capacity/ebx: int <- copy src-width capacity <- multiply src-height @@ -478,6 +484,12 @@ fn dither-pgm-unordered _src: (addr image), _dest: (addr image) { compare x, src-width break-if->= var initial-color/eax: byte <- _read-pgm-buffer src-data, x, y, src-width + # . scale to 255 levels + var initial-color-int/eax: int <- copy initial-color + var initial-color-f/xmm0: float <- convert initial-color-int + initial-color-f <- multiply scale-f + initial-color-int <- convert initial-color-f + var initial-color/eax: byte <- copy-byte initial-color-int var error/esi: int <- _read-dithering-error errors, x, y, src-width # error += (initial-color << 16) { |