1121 lines
36 KiB
Forth
1121 lines
36 KiB
Forth
# Loading images from disk, rendering images to screen.
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#
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# Currently supports ASCII Netpbm formats.
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# https://en.wikipedia.org/wiki/Netpbm#File_formats
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type image {
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type: int # supported types:
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# 1: portable bitmap (P1) - pixels 0 or 1
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# 2: portable greymap (P2) - pixels 1-byte greyscale values
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# 3: portable pixmap (P3) - pixels 3-byte rgb values
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max: int
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width: int
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height: int
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data: (handle array byte)
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}
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fn initialize-image _self: (addr image), in: (addr stream byte) {
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var self/esi: (addr image) <- copy _self
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var mode-storage: slice
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var mode/ecx: (addr slice) <- address mode-storage
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next-word-skipping-comments in, mode
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{
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var P1?/eax: boolean <- slice-equal? mode, "P1"
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compare P1?, 0/false
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break-if-=
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var type-a/eax: (addr int) <- get self, type
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copy-to *type-a, 1/ppm
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initialize-image-from-pbm self, in
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return
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}
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{
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var P2?/eax: boolean <- slice-equal? mode, "P2"
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compare P2?, 0/false
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break-if-=
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var type-a/eax: (addr int) <- get self, type
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copy-to *type-a, 2/pgm
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initialize-image-from-pgm self, in
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return
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}
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{
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var P3?/eax: boolean <- slice-equal? mode, "P3"
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compare P3?, 0/false
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break-if-=
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var type-a/eax: (addr int) <- get self, type
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copy-to *type-a, 3/ppm
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initialize-image-from-ppm self, in
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return
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}
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abort "initialize-image: unrecognized image type"
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}
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# dispatch to a few variants with mostly identical boilerplate
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# TODO: if we have more resolution we could actually use it to improve
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# dithering
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fn render-image screen: (addr screen), _img: (addr image), xmin: int, ymin: int, width: int, height: int {
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var img/esi: (addr image) <- copy _img
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var type-a/eax: (addr int) <- get img, type
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{
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compare *type-a, 1/pbm
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break-if-!=
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render-pbm-image screen, img, xmin, ymin, width, height
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return
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}
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{
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compare *type-a, 2/pgm
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break-if-!=
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var img2-storage: image
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var img2/edi: (addr image) <- address img2-storage
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dither-pgm-unordered img, img2
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render-raw-image screen, img2, xmin, ymin, width, height
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return
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}
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{
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compare *type-a, 3/ppm
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break-if-!=
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var img2-storage: image
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var img2/edi: (addr image) <- address img2-storage
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dither-ppm-unordered img, img2
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render-raw-image screen, img2, xmin, ymin, width, height
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return
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}
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#? abort "render-image: unrecognized image type"
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}
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## helpers
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# import a black-and-white ascii bitmap (each pixel is 0 or 1)
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fn initialize-image-from-pbm _self: (addr image), in: (addr stream byte) {
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var self/esi: (addr image) <- copy _self
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var curr-word-storage: slice
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var curr-word/ecx: (addr slice) <- address curr-word-storage
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# load width, height
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next-word-skipping-comments in, curr-word
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var tmp/eax: int <- parse-decimal-int-from-slice curr-word
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var width/edx: int <- copy tmp
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next-word-skipping-comments in, curr-word
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tmp <- parse-decimal-int-from-slice curr-word
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var height/ebx: int <- copy tmp
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# save width, height
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var dest/eax: (addr int) <- get self, width
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copy-to *dest, width
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dest <- get self, height
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copy-to *dest, height
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# initialize data
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var capacity/edx: int <- copy width
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capacity <- multiply height
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var data-ah/edi: (addr handle array byte) <- get self, data
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populate data-ah, capacity
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var _data/eax: (addr array byte) <- lookup *data-ah
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var data/edi: (addr array byte) <- copy _data
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var i/ebx: int <- copy 0
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{
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compare i, capacity
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break-if->=
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next-word-skipping-comments in, curr-word
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var src/eax: int <- parse-decimal-int-from-slice curr-word
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{
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var dest/ecx: (addr byte) <- index data, i
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copy-byte-to *dest, src
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}
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i <- increment
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loop
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}
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}
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# render a black-and-white ascii bitmap (each pixel is 0 or 1)
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fn render-pbm-image screen: (addr screen), _img: (addr image), xmin: int, ymin: int, width: int, height: int {
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var img/esi: (addr image) <- copy _img
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# yratio = height/img->height
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var img-height-a/eax: (addr int) <- get img, height
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var img-height/xmm0: float <- convert *img-height-a
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var yratio/xmm1: float <- convert height
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yratio <- divide img-height
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# xratio = width/img->width
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var img-width-a/eax: (addr int) <- get img, width
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var img-width/ebx: int <- copy *img-width-a
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var img-width-f/xmm0: float <- convert img-width
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var xratio/xmm2: float <- convert width
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xratio <- divide img-width-f
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# esi = img->data
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var img-data-ah/eax: (addr handle array byte) <- get img, data
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var _img-data/eax: (addr array byte) <- lookup *img-data-ah
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var img-data/esi: (addr array byte) <- copy _img-data
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var len/edi: int <- length img-data
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#
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var one/eax: int <- copy 1
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var one-f/xmm3: float <- convert one
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var width-f/xmm4: float <- convert width
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var height-f/xmm5: float <- convert height
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var zero/eax: int <- copy 0
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var zero-f/xmm0: float <- convert zero
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var y/xmm6: float <- copy zero-f
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{
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compare y, height-f
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break-if-float>=
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var imgy-f/xmm5: float <- copy y
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imgy-f <- divide yratio
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var imgy/edx: int <- truncate imgy-f
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var x/xmm7: float <- copy zero-f
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{
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compare x, width-f
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break-if-float>=
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var imgx-f/xmm5: float <- copy x
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imgx-f <- divide xratio
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var imgx/ecx: int <- truncate imgx-f
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var idx/eax: int <- copy imgy
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idx <- multiply img-width
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idx <- add imgx
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# error info in case we rounded wrong and 'index' will fail bounds-check
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compare idx, len
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{
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break-if-<
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set-cursor-position 0/screen, 0x20/x 0x20/y
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgx, 3/fg 0/bg
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgy, 4/fg 0/bg
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, idx, 5/fg 0/bg
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}
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var src-a/eax: (addr byte) <- index img-data, idx
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var src/eax: byte <- copy-byte *src-a
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var color-int/eax: int <- copy src
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{
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compare color-int, 0/black
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break-if-=
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color-int <- copy 0xf/white
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}
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var screenx/ecx: int <- convert x
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screenx <- add xmin
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var screeny/edx: int <- convert y
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screeny <- add ymin
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pixel screen, screenx, screeny, color-int
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x <- add one-f
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loop
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}
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y <- add one-f
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loop
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}
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}
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# import a greyscale ascii "greymap" (each pixel is a shade of grey from 0 to 255)
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fn initialize-image-from-pgm _self: (addr image), in: (addr stream byte) {
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var self/esi: (addr image) <- copy _self
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var curr-word-storage: slice
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var curr-word/ecx: (addr slice) <- address curr-word-storage
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# load width, height
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next-word-skipping-comments in, curr-word
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var tmp/eax: int <- parse-decimal-int-from-slice curr-word
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var width/edx: int <- copy tmp
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next-word-skipping-comments in, curr-word
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tmp <- parse-decimal-int-from-slice curr-word
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var height/ebx: int <- copy tmp
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# check and save color levels
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next-word-skipping-comments in, curr-word
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{
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tmp <- parse-decimal-int-from-slice curr-word
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compare tmp, 0xff
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break-if-=
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draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, "levels of grey is not 255; continuing and hoping for the best", 0x2b/fg 0/bg
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}
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var dest/edi: (addr int) <- get self, max
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copy-to *dest, tmp
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# save width, height
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dest <- get self, width
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copy-to *dest, width
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dest <- get self, height
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copy-to *dest, height
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# initialize data
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var capacity/edx: int <- copy width
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capacity <- multiply height
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var data-ah/edi: (addr handle array byte) <- get self, data
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populate data-ah, capacity
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var _data/eax: (addr array byte) <- lookup *data-ah
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var data/edi: (addr array byte) <- copy _data
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var i/ebx: int <- copy 0
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{
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compare i, capacity
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break-if->=
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next-word-skipping-comments in, curr-word
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var src/eax: int <- parse-decimal-int-from-slice curr-word
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{
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var dest/ecx: (addr byte) <- index data, i
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copy-byte-to *dest, src
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}
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i <- increment
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loop
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}
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}
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# render a greyscale ascii "greymap" (each pixel is a shade of grey from 0 to 255) by quantizing the shades
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fn render-pgm-image screen: (addr screen), _img: (addr image), xmin: int, ymin: int, width: int, height: int {
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var img/esi: (addr image) <- copy _img
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# yratio = height/img->height
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var img-height-a/eax: (addr int) <- get img, height
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var img-height/xmm0: float <- convert *img-height-a
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var yratio/xmm1: float <- convert height
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yratio <- divide img-height
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# xratio = width/img->width
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var img-width-a/eax: (addr int) <- get img, width
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var img-width/ebx: int <- copy *img-width-a
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var img-width-f/xmm0: float <- convert img-width
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var xratio/xmm2: float <- convert width
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xratio <- divide img-width-f
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# esi = img->data
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var img-data-ah/eax: (addr handle array byte) <- get img, data
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var _img-data/eax: (addr array byte) <- lookup *img-data-ah
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var img-data/esi: (addr array byte) <- copy _img-data
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var len/edi: int <- length img-data
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#
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var one/eax: int <- copy 1
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var one-f/xmm3: float <- convert one
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var width-f/xmm4: float <- convert width
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var height-f/xmm5: float <- convert height
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var zero/eax: int <- copy 0
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var zero-f/xmm0: float <- convert zero
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var y/xmm6: float <- copy zero-f
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{
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compare y, height-f
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break-if-float>=
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var imgy-f/xmm5: float <- copy y
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imgy-f <- divide yratio
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var imgy/edx: int <- truncate imgy-f
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var x/xmm7: float <- copy zero-f
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{
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compare x, width-f
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break-if-float>=
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var imgx-f/xmm5: float <- copy x
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imgx-f <- divide xratio
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var imgx/ecx: int <- truncate imgx-f
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var idx/eax: int <- copy imgy
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idx <- multiply img-width
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idx <- add imgx
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# error info in case we rounded wrong and 'index' will fail bounds-check
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compare idx, len
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{
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break-if-<
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set-cursor-position 0/screen, 0x20/x 0x20/y
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgx, 3/fg 0/bg
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgy, 4/fg 0/bg
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draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, idx, 5/fg 0/bg
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}
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var src-a/eax: (addr byte) <- index img-data, idx
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var src/eax: byte <- copy-byte *src-a
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var color-int/eax: int <- nearest-grey src
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var screenx/ecx: int <- convert x
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screenx <- add xmin
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var screeny/edx: int <- convert y
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screeny <- add ymin
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pixel screen, screenx, screeny, color-int
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x <- add one-f
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loop
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}
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y <- add one-f
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loop
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}
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}
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fn nearest-grey level-255: byte -> _/eax: int {
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var result/eax: int <- copy level-255
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result <- shift-right 4
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result <- add 0x10
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return result
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}
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fn dither-pgm-unordered-monochrome _src: (addr image), _dest: (addr image) {
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var src/esi: (addr image) <- copy _src
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var dest/edi: (addr image) <- copy _dest
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# copy 'width'
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var src-width-a/eax: (addr int) <- get src, width
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var tmp/eax: int <- copy *src-width-a
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var src-width: int
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copy-to src-width, tmp
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{
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var dest-width-a/edx: (addr int) <- get dest, width
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copy-to *dest-width-a, tmp
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}
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# copy 'height'
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var src-height-a/eax: (addr int) <- get src, height
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var tmp/eax: int <- copy *src-height-a
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var src-height: int
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copy-to src-height, tmp
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{
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var dest-height-a/ecx: (addr int) <- get dest, height
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copy-to *dest-height-a, tmp
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}
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# transform 'data'
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var capacity/ebx: int <- copy src-width
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capacity <- multiply src-height
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var dest/edi: (addr image) <- copy _dest
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var dest-data-ah/eax: (addr handle array byte) <- get dest, data
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populate dest-data-ah, capacity
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var _dest-data/eax: (addr array byte) <- lookup *dest-data-ah
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var dest-data/edi: (addr array byte) <- copy _dest-data
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# needs a buffer to temporarily hold more than 256 levels of precision
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var errors-storage: (array int 0xc0000)
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var errors/ebx: (addr array int) <- address errors-storage
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var src-data-ah/eax: (addr handle array byte) <- get src, data
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var _src-data/eax: (addr array byte) <- lookup *src-data-ah
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var src-data/esi: (addr array byte) <- copy _src-data
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var y/edx: int <- copy 0
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{
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compare y, src-height
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break-if->=
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var x/ecx: int <- copy 0
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{
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compare x, src-width
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break-if->=
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var curr/eax: byte <- _read-pgm-buffer src-data, x, y, src-width
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var curr-int/eax: int <- copy curr
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curr-int <- shift-left 0x10 # we have 32 bits; we'll use 16 bits for the fraction and leave 8 for unanticipated overflow
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var error/esi: int <- _read-dithering-error errors, x, y, src-width
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error <- add curr-int
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$_dither-pgm-unordered-monochrome:update-error: {
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compare error, 0x800000
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{
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break-if->=
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_write-raw-buffer dest-data, x, y, src-width, 0/black
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break $_dither-pgm-unordered-monochrome:update-error
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}
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_write-raw-buffer dest-data, x, y, src-width, 1/white
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error <- subtract 0xff0000
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}
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_diffuse-dithering-error-floyd-steinberg errors, x, y, src-width, src-height, error
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x <- increment
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loop
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}
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move-cursor-to-left-margin-of-next-line 0/screen
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y <- increment
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loop
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}
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}
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fn dither-pgm-unordered _src: (addr image), _dest: (addr image) {
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var src/esi: (addr image) <- copy _src
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var dest/edi: (addr image) <- copy _dest
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# copy 'width'
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var src-width-a/eax: (addr int) <- get src, width
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var tmp/eax: int <- copy *src-width-a
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var src-width: int
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copy-to src-width, tmp
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{
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var dest-width-a/edx: (addr int) <- get dest, width
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copy-to *dest-width-a, tmp
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}
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# copy 'height'
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var src-height-a/eax: (addr int) <- get src, height
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var tmp/eax: int <- copy *src-height-a
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var src-height: int
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copy-to src-height, tmp
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{
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var dest-height-a/ecx: (addr int) <- get dest, height
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copy-to *dest-height-a, tmp
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}
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# compute scaling factor 255/max
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var target-scale/eax: int <- copy 0xff
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var scale-f/xmm7: float <- convert target-scale
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var src-max-a/eax: (addr int) <- get src, max
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var tmp-f/xmm0: float <- convert *src-max-a
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scale-f <- divide tmp-f
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# transform 'data'
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var capacity/ebx: int <- copy src-width
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capacity <- multiply src-height
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var dest/edi: (addr image) <- copy _dest
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var dest-data-ah/eax: (addr handle array byte) <- get dest, data
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populate dest-data-ah, capacity
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var _dest-data/eax: (addr array byte) <- lookup *dest-data-ah
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var dest-data/edi: (addr array byte) <- copy _dest-data
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# needs a buffer to temporarily hold more than 256 levels of precision
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var errors-storage: (array int 0xc0000)
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var errors/ebx: (addr array int) <- address errors-storage
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var src-data-ah/eax: (addr handle array byte) <- get src, data
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var _src-data/eax: (addr array byte) <- lookup *src-data-ah
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var src-data/esi: (addr array byte) <- copy _src-data
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var y/edx: int <- copy 0
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{
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compare y, src-height
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break-if->=
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var x/ecx: int <- copy 0
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{
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compare x, src-width
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break-if->=
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var initial-color/eax: byte <- _read-pgm-buffer src-data, x, y, src-width
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# . scale to 255 levels
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var initial-color-int/eax: int <- copy initial-color
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var initial-color-f/xmm0: float <- convert initial-color-int
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initial-color-f <- multiply scale-f
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initial-color-int <- convert initial-color-f
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var error/esi: int <- _read-dithering-error errors, x, y, src-width
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# error += (initial-color << 16)
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{
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|
var tmp/eax: int <- copy initial-color-int
|
|
tmp <- shift-left 0x10 # we have 32 bits; we'll use 16 bits for the fraction and leave 8 for unanticipated overflow
|
|
error <- add tmp
|
|
}
|
|
# nearest-color = nearest(error >> 16)
|
|
var nearest-color/eax: int <- copy error
|
|
nearest-color <- shift-right-signed 0x10
|
|
{
|
|
compare nearest-color, 0
|
|
break-if->=
|
|
nearest-color <- copy 0
|
|
}
|
|
{
|
|
compare nearest-color, 0xf0
|
|
break-if-<=
|
|
nearest-color <- copy 0xf0
|
|
}
|
|
# . truncate last 4 bits
|
|
nearest-color <- and 0xf0
|
|
# error -= (nearest-color << 16)
|
|
{
|
|
var tmp/eax: int <- copy nearest-color
|
|
tmp <- shift-left 0x10
|
|
error <- subtract tmp
|
|
}
|
|
# color-index = (nearest-color >> 4 + 16)
|
|
var color-index/eax: int <- copy nearest-color
|
|
color-index <- shift-right 4
|
|
color-index <- add 0x10
|
|
var color-index-byte/eax: byte <- copy-byte color-index
|
|
_write-raw-buffer dest-data, x, y, src-width, color-index-byte
|
|
_diffuse-dithering-error-floyd-steinberg errors, x, y, src-width, src-height, error
|
|
x <- increment
|
|
loop
|
|
}
|
|
y <- increment
|
|
loop
|
|
}
|
|
}
|
|
|
|
# Use Floyd-Steinberg algorithm for diffusing error at x, y in a 2D grid of
|
|
# dimensions (width, height)
|
|
#
|
|
# https://tannerhelland.com/2012/12/28/dithering-eleven-algorithms-source-code.html
|
|
#
|
|
# Error is currently a fixed-point number with 16-bit fraction. But
|
|
# interestingly this function doesn't care about that.
|
|
fn _diffuse-dithering-error-floyd-steinberg errors: (addr array int), x: int, y: int, width: int, height: int, error: int {
|
|
{
|
|
compare error, 0
|
|
break-if-!=
|
|
return
|
|
}
|
|
var width-1/esi: int <- copy width
|
|
width-1 <- decrement
|
|
var height-1/edi: int <- copy height
|
|
height-1 <- decrement
|
|
# delta = error/16
|
|
#? show-errors errors, width, height, x, y
|
|
var delta/ecx: int <- copy error
|
|
delta <- shift-right-signed 4
|
|
# In Floyd-Steinberg, each pixel X transmits its errors to surrounding
|
|
# pixels in the following proportion:
|
|
# X 7/16
|
|
# 3/16 5/16 1/16
|
|
var x/edx: int <- copy x
|
|
{
|
|
compare x, width-1
|
|
break-if->=
|
|
var tmp/eax: int <- copy 7
|
|
tmp <- multiply delta
|
|
var xright/edx: int <- copy x
|
|
xright <- increment
|
|
_accumulate-dithering-error errors, xright, y, width, tmp
|
|
}
|
|
var y/ebx: int <- copy y
|
|
{
|
|
compare y, height-1
|
|
break-if-<
|
|
return
|
|
}
|
|
var ybelow: int
|
|
copy-to ybelow, y
|
|
increment ybelow
|
|
{
|
|
compare x, 0
|
|
break-if-<=
|
|
var tmp/eax: int <- copy 3
|
|
tmp <- multiply delta
|
|
var xleft/edx: int <- copy x
|
|
xleft <- decrement
|
|
_accumulate-dithering-error errors, xleft, ybelow, width, tmp
|
|
}
|
|
{
|
|
var tmp/eax: int <- copy 5
|
|
tmp <- multiply delta
|
|
_accumulate-dithering-error errors, x, ybelow, width, tmp
|
|
}
|
|
{
|
|
compare x, width-1
|
|
break-if->=
|
|
var xright/edx: int <- copy x
|
|
xright <- increment
|
|
_accumulate-dithering-error errors, xright, ybelow, width, delta
|
|
}
|
|
#? show-errors errors, width, height, x, y
|
|
}
|
|
|
|
fn _accumulate-dithering-error errors: (addr array int), x: int, y: int, width: int, error: int {
|
|
var curr/esi: int <- _read-dithering-error errors, x, y, width
|
|
curr <- add error
|
|
_write-dithering-error errors, x, y, width, curr
|
|
}
|
|
|
|
fn _read-dithering-error _errors: (addr array int), x: int, y: int, width: int -> _/esi: int {
|
|
var errors/esi: (addr array int) <- copy _errors
|
|
var idx/ecx: int <- copy y
|
|
idx <- multiply width
|
|
idx <- add x
|
|
var result-a/eax: (addr int) <- index errors, idx
|
|
return *result-a
|
|
}
|
|
|
|
fn _write-dithering-error _errors: (addr array int), x: int, y: int, width: int, val: int {
|
|
var errors/esi: (addr array int) <- copy _errors
|
|
var idx/ecx: int <- copy y
|
|
idx <- multiply width
|
|
idx <- add x
|
|
#? draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, idx, 7/fg 0/bg
|
|
#? move-cursor-to-left-margin-of-next-line 0/screen
|
|
var src/eax: int <- copy val
|
|
var dest-a/edi: (addr int) <- index errors, idx
|
|
copy-to *dest-a, src
|
|
}
|
|
|
|
fn _read-pgm-buffer _buf: (addr array byte), x: int, y: int, width: int -> _/eax: byte {
|
|
var buf/esi: (addr array byte) <- copy _buf
|
|
var idx/ecx: int <- copy y
|
|
idx <- multiply width
|
|
idx <- add x
|
|
var result-a/eax: (addr byte) <- index buf, idx
|
|
var result/eax: byte <- copy-byte *result-a
|
|
return result
|
|
}
|
|
|
|
fn _write-raw-buffer _buf: (addr array byte), x: int, y: int, width: int, val: byte {
|
|
var buf/esi: (addr array byte) <- copy _buf
|
|
var idx/ecx: int <- copy y
|
|
idx <- multiply width
|
|
idx <- add x
|
|
var src/eax: byte <- copy val
|
|
var dest-a/edi: (addr byte) <- index buf, idx
|
|
copy-byte-to *dest-a, src
|
|
}
|
|
|
|
# some debugging helpers
|
|
fn show-errors errors: (addr array int), width: int, height: int, x: int, y: int {
|
|
compare y, 1
|
|
{
|
|
break-if-=
|
|
return
|
|
}
|
|
compare x, 0
|
|
{
|
|
break-if-=
|
|
return
|
|
}
|
|
var y/edx: int <- copy 0
|
|
{
|
|
compare y, height
|
|
break-if->=
|
|
var x/ecx: int <- copy 0
|
|
{
|
|
compare x, width
|
|
break-if->=
|
|
var error/esi: int <- _read-dithering-error errors, x, y, width
|
|
psd "e", error, 5/fg, x, y
|
|
x <- increment
|
|
loop
|
|
}
|
|
move-cursor-to-left-margin-of-next-line 0/screen
|
|
y <- increment
|
|
loop
|
|
}
|
|
}
|
|
|
|
fn psd s: (addr array byte), d: int, fg: int, x: int, y: int {
|
|
{
|
|
compare y, 0x18
|
|
break-if->=
|
|
return
|
|
}
|
|
{
|
|
compare y, 0x1c
|
|
break-if-<=
|
|
return
|
|
}
|
|
{
|
|
compare x, 0x40
|
|
break-if->=
|
|
return
|
|
}
|
|
#? {
|
|
#? compare x, 0x48
|
|
#? break-if-<=
|
|
#? return
|
|
#? }
|
|
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, s, 7/fg 0/bg
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, d, fg 0/bg
|
|
}
|
|
|
|
fn psx s: (addr array byte), d: int, fg: int, x: int, y: int {
|
|
#? {
|
|
#? compare y, 0x60
|
|
#? break-if->=
|
|
#? return
|
|
#? }
|
|
#? {
|
|
#? compare y, 0x6c
|
|
#? break-if-<=
|
|
#? return
|
|
#? }
|
|
{
|
|
compare x, 0x20
|
|
break-if->=
|
|
return
|
|
}
|
|
#? {
|
|
#? compare x, 0x6c
|
|
#? break-if-<=
|
|
#? return
|
|
#? }
|
|
draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, s, 7/fg 0/bg
|
|
draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, d, fg 0/bg
|
|
}
|
|
|
|
# import a color ascii "pixmap" (each pixel consists of 3 shades of r/g/b from 0 to 255)
|
|
fn initialize-image-from-ppm _self: (addr image), in: (addr stream byte) {
|
|
var self/esi: (addr image) <- copy _self
|
|
var curr-word-storage: slice
|
|
var curr-word/ecx: (addr slice) <- address curr-word-storage
|
|
# load width, height
|
|
next-word-skipping-comments in, curr-word
|
|
var tmp/eax: int <- parse-decimal-int-from-slice curr-word
|
|
var width/edx: int <- copy tmp
|
|
next-word-skipping-comments in, curr-word
|
|
tmp <- parse-decimal-int-from-slice curr-word
|
|
var height/ebx: int <- copy tmp
|
|
next-word-skipping-comments in, curr-word
|
|
# check color levels
|
|
{
|
|
tmp <- parse-decimal-int-from-slice curr-word
|
|
compare tmp, 0xff
|
|
break-if-=
|
|
abort "initialize-image-from-ppm: supports exactly 255 levels per rgb channel"
|
|
}
|
|
var dest/edi: (addr int) <- get self, max
|
|
copy-to *dest, tmp
|
|
# save width, height
|
|
dest <- get self, width
|
|
copy-to *dest, width
|
|
dest <- get self, height
|
|
copy-to *dest, height
|
|
# initialize data
|
|
var capacity/edx: int <- copy width
|
|
capacity <- multiply height
|
|
# . multiply by 3 for the r/g/b channels
|
|
var tmp/eax: int <- copy capacity
|
|
tmp <- shift-left 1
|
|
capacity <- add tmp
|
|
#
|
|
var data-ah/edi: (addr handle array byte) <- get self, data
|
|
populate data-ah, capacity
|
|
var _data/eax: (addr array byte) <- lookup *data-ah
|
|
var data/edi: (addr array byte) <- copy _data
|
|
var i/ebx: int <- copy 0
|
|
{
|
|
compare i, capacity
|
|
break-if->=
|
|
next-word-skipping-comments in, curr-word
|
|
var src/eax: int <- parse-decimal-int-from-slice curr-word
|
|
{
|
|
var dest/ecx: (addr byte) <- index data, i
|
|
copy-byte-to *dest, src
|
|
}
|
|
i <- increment
|
|
loop
|
|
}
|
|
}
|
|
|
|
# import a color ascii "pixmap" (each pixel consists of 3 shades of r/g/b from 0 to 255)
|
|
fn render-ppm-image screen: (addr screen), _img: (addr image), xmin: int, ymin: int, width: int, height: int {
|
|
var img/esi: (addr image) <- copy _img
|
|
# yratio = height/img->height
|
|
var img-height-a/eax: (addr int) <- get img, height
|
|
var img-height/xmm0: float <- convert *img-height-a
|
|
var yratio/xmm1: float <- convert height
|
|
yratio <- divide img-height
|
|
# xratio = width/img->width
|
|
var img-width-a/eax: (addr int) <- get img, width
|
|
var img-width/ebx: int <- copy *img-width-a
|
|
var img-width-f/xmm0: float <- convert img-width
|
|
var xratio/xmm2: float <- convert width
|
|
xratio <- divide img-width-f
|
|
# esi = img->data
|
|
var img-data-ah/eax: (addr handle array byte) <- get img, data
|
|
var _img-data/eax: (addr array byte) <- lookup *img-data-ah
|
|
var img-data/esi: (addr array byte) <- copy _img-data
|
|
var len/edi: int <- length img-data
|
|
#
|
|
var one/eax: int <- copy 1
|
|
var one-f/xmm3: float <- convert one
|
|
var width-f/xmm4: float <- convert width
|
|
var height-f/xmm5: float <- convert height
|
|
var zero/eax: int <- copy 0
|
|
var zero-f/xmm0: float <- convert zero
|
|
var y/xmm6: float <- copy zero-f
|
|
{
|
|
compare y, height-f
|
|
break-if-float>=
|
|
var imgy-f/xmm5: float <- copy y
|
|
imgy-f <- divide yratio
|
|
var imgy/edx: int <- truncate imgy-f
|
|
var x/xmm7: float <- copy zero-f
|
|
{
|
|
compare x, width-f
|
|
break-if-float>=
|
|
var imgx-f/xmm5: float <- copy x
|
|
imgx-f <- divide xratio
|
|
var imgx/ecx: int <- truncate imgx-f
|
|
var idx/eax: int <- copy imgy
|
|
idx <- multiply img-width
|
|
idx <- add imgx
|
|
# . multiply by 3 for the r/g/b channels
|
|
{
|
|
var tmp/ecx: int <- copy idx
|
|
tmp <- shift-left 1
|
|
idx <- add tmp
|
|
}
|
|
# error info in case we rounded wrong and 'index' will fail bounds-check
|
|
compare idx, len
|
|
{
|
|
break-if-<
|
|
set-cursor-position 0/screen, 0x20/x 0x20/y
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgx, 3/fg 0/bg
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgy, 4/fg 0/bg
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, idx, 5/fg 0/bg
|
|
}
|
|
# r channel
|
|
var r: int
|
|
{
|
|
var src-a/eax: (addr byte) <- index img-data, idx
|
|
var src/eax: byte <- copy-byte *src-a
|
|
copy-to r, src
|
|
}
|
|
idx <- increment
|
|
# g channel
|
|
var g: int
|
|
{
|
|
var src-a/eax: (addr byte) <- index img-data, idx
|
|
var src/eax: byte <- copy-byte *src-a
|
|
copy-to g, src
|
|
}
|
|
idx <- increment
|
|
# b channel
|
|
var b: int
|
|
{
|
|
var src-a/eax: (addr byte) <- index img-data, idx
|
|
var src/eax: byte <- copy-byte *src-a
|
|
copy-to b, src
|
|
}
|
|
idx <- increment
|
|
# plot nearest color
|
|
var color/eax: int <- nearest-color-euclidean r, g, b
|
|
var screenx/ecx: int <- convert x
|
|
screenx <- add xmin
|
|
var screeny/edx: int <- convert y
|
|
screeny <- add ymin
|
|
pixel screen, screenx, screeny, color
|
|
x <- add one-f
|
|
loop
|
|
}
|
|
y <- add one-f
|
|
loop
|
|
}
|
|
}
|
|
|
|
fn dither-ppm-unordered _src: (addr image), _dest: (addr image) {
|
|
var src/esi: (addr image) <- copy _src
|
|
var dest/edi: (addr image) <- copy _dest
|
|
# copy 'width'
|
|
var src-width-a/eax: (addr int) <- get src, width
|
|
var tmp/eax: int <- copy *src-width-a
|
|
var src-width: int
|
|
copy-to src-width, tmp
|
|
{
|
|
var dest-width-a/edx: (addr int) <- get dest, width
|
|
copy-to *dest-width-a, tmp
|
|
}
|
|
# copy 'height'
|
|
var src-height-a/eax: (addr int) <- get src, height
|
|
var tmp/eax: int <- copy *src-height-a
|
|
var src-height: int
|
|
copy-to src-height, tmp
|
|
{
|
|
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
|
|
# allocate 'data'
|
|
var capacity/ebx: int <- copy src-width
|
|
capacity <- multiply src-height
|
|
var dest/edi: (addr image) <- copy _dest
|
|
var dest-data-ah/eax: (addr handle array byte) <- get dest, data
|
|
populate dest-data-ah, capacity
|
|
var _dest-data/eax: (addr array byte) <- lookup *dest-data-ah
|
|
var dest-data/edi: (addr array byte) <- copy _dest-data
|
|
# error buffers per r/g/b channel
|
|
var red-errors-storage: (array int 0xc0000)
|
|
var tmp/eax: (addr array int) <- address red-errors-storage
|
|
var red-errors: (addr array int)
|
|
copy-to red-errors, tmp
|
|
var green-errors-storage: (array int 0xc0000)
|
|
var tmp/eax: (addr array int) <- address green-errors-storage
|
|
var green-errors: (addr array int)
|
|
copy-to green-errors, tmp
|
|
var blue-errors-storage: (array int 0xc0000)
|
|
var tmp/eax: (addr array int) <- address blue-errors-storage
|
|
var blue-errors: (addr array int)
|
|
copy-to blue-errors, tmp
|
|
# transform 'data'
|
|
var src-data-ah/eax: (addr handle array byte) <- get src, data
|
|
var _src-data/eax: (addr array byte) <- lookup *src-data-ah
|
|
var src-data/esi: (addr array byte) <- copy _src-data
|
|
var y/edx: int <- copy 0
|
|
{
|
|
compare y, src-height
|
|
break-if->=
|
|
var x/ecx: int <- copy 0
|
|
{
|
|
compare x, src-width
|
|
break-if->=
|
|
# - update errors and compute color levels for current pixel in each channel
|
|
# update red-error with current image pixel
|
|
var red-error: int
|
|
{
|
|
var tmp/esi: int <- _read-dithering-error red-errors, x, y, src-width
|
|
copy-to red-error, tmp
|
|
}
|
|
{
|
|
var tmp/eax: int <- _ppm-error src-data, x, y, src-width, 0/red, scale-f
|
|
add-to red-error, tmp
|
|
}
|
|
# recompute red channel for current pixel
|
|
var red-level: int
|
|
{
|
|
var tmp/eax: int <- _error-to-ppm-channel red-error
|
|
copy-to red-level, tmp
|
|
}
|
|
# update green-error with current image pixel
|
|
var green-error: int
|
|
{
|
|
var tmp/esi: int <- _read-dithering-error green-errors, x, y, src-width
|
|
copy-to green-error, tmp
|
|
}
|
|
{
|
|
var tmp/eax: int <- _ppm-error src-data, x, y, src-width, 1/green, scale-f
|
|
add-to green-error, tmp
|
|
}
|
|
# recompute green channel for current pixel
|
|
var green-level: int
|
|
{
|
|
var tmp/eax: int <- _error-to-ppm-channel green-error
|
|
copy-to green-level, tmp
|
|
}
|
|
# update blue-error with current image pixel
|
|
var blue-error: int
|
|
{
|
|
var tmp/esi: int <- _read-dithering-error blue-errors, x, y, src-width
|
|
copy-to blue-error, tmp
|
|
}
|
|
{
|
|
var tmp/eax: int <- _ppm-error src-data, x, y, src-width, 2/blue, scale-f
|
|
add-to blue-error, tmp
|
|
}
|
|
# recompute blue channel for current pixel
|
|
var blue-level: int
|
|
{
|
|
var tmp/eax: int <- _error-to-ppm-channel blue-error
|
|
copy-to blue-level, tmp
|
|
}
|
|
# - figure out the nearest color
|
|
var nearest-color-index/eax: int <- nearest-color-euclidean red-level, green-level, blue-level
|
|
{
|
|
var nearest-color-index-byte/eax: byte <- copy-byte nearest-color-index
|
|
_write-raw-buffer dest-data, x, y, src-width, nearest-color-index-byte
|
|
}
|
|
# - diffuse errors
|
|
var red-level: int
|
|
var green-level: int
|
|
var blue-level: int
|
|
{
|
|
var tmp-red-level/ecx: int <- copy 0
|
|
var tmp-green-level/edx: int <- copy 0
|
|
var tmp-blue-level/ebx: int <- copy 0
|
|
tmp-red-level, tmp-green-level, tmp-blue-level <- color-rgb nearest-color-index
|
|
copy-to red-level, tmp-red-level
|
|
copy-to green-level, tmp-green-level
|
|
copy-to blue-level, tmp-blue-level
|
|
}
|
|
# update red-error
|
|
var red-level-error/eax: int <- copy red-level
|
|
red-level-error <- shift-left 0x10
|
|
subtract-from red-error, red-level-error
|
|
_diffuse-dithering-error-floyd-steinberg red-errors, x, y, src-width, src-height, red-error
|
|
# update green-error
|
|
var green-level-error/eax: int <- copy green-level
|
|
green-level-error <- shift-left 0x10
|
|
subtract-from green-error, green-level-error
|
|
_diffuse-dithering-error-floyd-steinberg green-errors, x, y, src-width, src-height, green-error
|
|
# update blue-error
|
|
var blue-level-error/eax: int <- copy blue-level
|
|
blue-level-error <- shift-left 0x10
|
|
subtract-from blue-error, blue-level-error
|
|
_diffuse-dithering-error-floyd-steinberg blue-errors, x, y, src-width, src-height, blue-error
|
|
#
|
|
x <- increment
|
|
loop
|
|
}
|
|
y <- increment
|
|
loop
|
|
}
|
|
}
|
|
|
|
# convert a single channel for a single image pixel to error space
|
|
fn _ppm-error buf: (addr array byte), x: int, y: int, width: int, channel: int, _scale-f: float -> _/eax: int {
|
|
# current image pixel
|
|
var initial-level/eax: byte <- _read-ppm-buffer buf, x, y, width, channel
|
|
# scale to 255 levels
|
|
var initial-level-int/eax: int <- copy initial-level
|
|
var initial-level-f/xmm0: float <- convert initial-level-int
|
|
var scale-f/xmm1: float <- copy _scale-f
|
|
initial-level-f <- multiply scale-f
|
|
initial-level-int <- convert initial-level-f
|
|
# switch to fixed-point with 16 bits of precision
|
|
initial-level-int <- shift-left 0x10
|
|
return initial-level-int
|
|
}
|
|
|
|
fn _error-to-ppm-channel error: int -> _/eax: int {
|
|
# clamp(error >> 16)
|
|
var result/esi: int <- copy error
|
|
result <- shift-right-signed 0x10
|
|
{
|
|
compare result, 0
|
|
break-if->=
|
|
result <- copy 0
|
|
}
|
|
{
|
|
compare result, 0xff
|
|
break-if-<=
|
|
result <- copy 0xff
|
|
}
|
|
return result
|
|
}
|
|
|
|
# read from a buffer containing alternating bytes from r/g/b channels
|
|
fn _read-ppm-buffer _buf: (addr array byte), x: int, y: int, width: int, channel: int -> _/eax: byte {
|
|
var buf/esi: (addr array byte) <- copy _buf
|
|
var idx/ecx: int <- copy y
|
|
idx <- multiply width
|
|
idx <- add x
|
|
var byte-idx/edx: int <- copy 3
|
|
byte-idx <- multiply idx
|
|
byte-idx <- add channel
|
|
var result-a/eax: (addr byte) <- index buf, byte-idx
|
|
var result/eax: byte <- copy-byte *result-a
|
|
return result
|
|
}
|
|
|
|
# each byte in the image data is a color of the current palette
|
|
fn render-raw-image screen: (addr screen), _img: (addr image), xmin: int, ymin: int, width: int, height: int {
|
|
var img/esi: (addr image) <- copy _img
|
|
# yratio = height/img->height
|
|
var img-height-a/eax: (addr int) <- get img, height
|
|
var img-height/xmm0: float <- convert *img-height-a
|
|
var yratio/xmm1: float <- convert height
|
|
yratio <- divide img-height
|
|
# xratio = width/img->width
|
|
var img-width-a/eax: (addr int) <- get img, width
|
|
var img-width/ebx: int <- copy *img-width-a
|
|
var img-width-f/xmm0: float <- convert img-width
|
|
var xratio/xmm2: float <- convert width
|
|
xratio <- divide img-width-f
|
|
# esi = img->data
|
|
var img-data-ah/eax: (addr handle array byte) <- get img, data
|
|
var _img-data/eax: (addr array byte) <- lookup *img-data-ah
|
|
var img-data/esi: (addr array byte) <- copy _img-data
|
|
var len/edi: int <- length img-data
|
|
#
|
|
var one/eax: int <- copy 1
|
|
var one-f/xmm3: float <- convert one
|
|
var width-f/xmm4: float <- convert width
|
|
var height-f/xmm5: float <- convert height
|
|
var zero/eax: int <- copy 0
|
|
var zero-f/xmm0: float <- convert zero
|
|
var y/xmm6: float <- copy zero-f
|
|
{
|
|
compare y, height-f
|
|
break-if-float>=
|
|
var imgy-f/xmm5: float <- copy y
|
|
imgy-f <- divide yratio
|
|
var imgy/edx: int <- truncate imgy-f
|
|
var x/xmm7: float <- copy zero-f
|
|
{
|
|
compare x, width-f
|
|
break-if-float>=
|
|
var imgx-f/xmm5: float <- copy x
|
|
imgx-f <- divide xratio
|
|
var imgx/ecx: int <- truncate imgx-f
|
|
var idx/eax: int <- copy imgy
|
|
idx <- multiply img-width
|
|
idx <- add imgx
|
|
# error info in case we rounded wrong and 'index' will fail bounds-check
|
|
compare idx, len
|
|
{
|
|
break-if-<
|
|
set-cursor-position 0/screen, 0x20/x 0x20/y
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgx, 3/fg 0/bg
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, imgy, 4/fg 0/bg
|
|
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, idx, 5/fg 0/bg
|
|
}
|
|
var color-a/eax: (addr byte) <- index img-data, idx
|
|
var color/eax: byte <- copy-byte *color-a
|
|
var color-int/eax: int <- copy color
|
|
var screenx/ecx: int <- convert x
|
|
screenx <- add xmin
|
|
var screeny/edx: int <- convert y
|
|
screeny <- add ymin
|
|
pixel screen, screenx, screeny, color-int
|
|
x <- add one-f
|
|
loop
|
|
}
|
|
y <- add one-f
|
|
loop
|
|
}
|
|
}
|
|
|
|
fn scale-image-height _img: (addr image), width: int -> _/ebx: int {
|
|
var img/esi: (addr image) <- copy _img
|
|
var img-height/eax: (addr int) <- get img, height
|
|
var result-f/xmm0: float <- convert *img-height
|
|
var img-width/eax: (addr int) <- get img, width
|
|
var img-width-f/xmm1: float <- convert *img-width
|
|
result-f <- divide img-width-f
|
|
var width-f/xmm1: float <- convert width
|
|
result-f <- multiply width-f
|
|
var result/ebx: int <- convert result-f
|
|
return result
|
|
}
|
|
|
|
fn next-word-skipping-comments line: (addr stream byte), out: (addr slice) {
|
|
next-word line, out
|
|
var retry?/eax: boolean <- slice-starts-with? out, "#"
|
|
compare retry?, 0/false
|
|
loop-if-!=
|
|
}
|