primitive: convert r/g/b to h/s/l
This commit is contained in:
Kartik K. Agaram
parent
2c0539e6fa
commit
673025b346
|
|
@ -0,0 +1,234 @@
|
|||
# Hue/saturation/luminance for an rgb triple.
|
||||
# rgb are in [0, 256)
|
||||
# hsl are also returned in [0, 256)
|
||||
# from https://www.niwa.nu/2013/05/math-behind-colorspace-conversions-rgb-hsl
|
||||
fn hsl r: int, g: int, b: int -> _/ecx: int, _/edx: int, _/ebx: int {
|
||||
var _max/eax: int <- maximum r, g
|
||||
_max <- maximum _max, b
|
||||
var max/ecx: int <- copy _max
|
||||
var _min/eax: int <- minimum r, g
|
||||
_min <- minimum _min, b
|
||||
var min/edx: int <- copy _min
|
||||
var luminance/ebx: int <- copy min
|
||||
luminance <- add max
|
||||
luminance <- shift-right 1 # TODO: round up instead of down
|
||||
# if rgb are all equal, it's a shade of grey
|
||||
compare min, max
|
||||
{
|
||||
break-if-!=
|
||||
return 0, 0, luminance
|
||||
}
|
||||
# saturation =
|
||||
# luminance < 128 | 255*(max-min)/ (max+min)
|
||||
# otherwise | 255*(max-min)/(2*255 - (max+min))
|
||||
var nr/esi: int <- copy max
|
||||
nr <- subtract min
|
||||
var dr/eax: int <- copy 0
|
||||
compare luminance, 0x80
|
||||
{
|
||||
break-if->=
|
||||
dr <- copy max
|
||||
dr <- add min
|
||||
}
|
||||
{
|
||||
break-if-<
|
||||
dr <- copy 0xff
|
||||
dr <- shift-left 1
|
||||
dr <- subtract max
|
||||
dr <- subtract min
|
||||
}
|
||||
var q/xmm0: float <- convert nr
|
||||
var tmp/xmm1: float <- convert dr
|
||||
q <- divide tmp
|
||||
var int-255/eax: int <- copy 0xff
|
||||
tmp <- convert int-255
|
||||
q <- multiply tmp
|
||||
var saturation/esi: int <- convert q
|
||||
# hue =
|
||||
# red is max | 256.0/6* (g-b)/(max-min)
|
||||
# green is max | 256.0/6*(2.0 + (b-r)/(max-min))
|
||||
# blue is max | 256.0/6*(4.0 + (r-g)/(max-min))
|
||||
var zero/eax: int <- copy 0
|
||||
var hue-f/xmm0: float <- convert zero
|
||||
var dr/eax: int <- copy max
|
||||
dr <- subtract min
|
||||
var dr-f/xmm1: float <- convert dr
|
||||
$hsl:compute-hue-normalized: {
|
||||
compare r, max
|
||||
{
|
||||
break-if-!=
|
||||
var nr/eax: int <- copy g
|
||||
nr <- subtract b
|
||||
hue-f <- convert nr
|
||||
hue-f <- divide dr-f
|
||||
break $hsl:compute-hue-normalized
|
||||
}
|
||||
compare g, max
|
||||
{
|
||||
break-if-!=
|
||||
var nr/eax: int <- copy b
|
||||
nr <- subtract r
|
||||
var f/xmm2: float <- convert nr
|
||||
f <- divide dr-f
|
||||
var two/ecx: int <- copy 2
|
||||
hue-f <- convert two
|
||||
hue-f <- add f
|
||||
break $hsl:compute-hue-normalized
|
||||
}
|
||||
compare b, max
|
||||
{
|
||||
break-if-!=
|
||||
var nr/eax: int <- copy r
|
||||
nr <- subtract g
|
||||
var f/xmm2: float <- convert nr
|
||||
f <- divide dr-f
|
||||
var two/ecx: int <- copy 4
|
||||
hue-f <- convert two
|
||||
hue-f <- add f
|
||||
break $hsl:compute-hue-normalized
|
||||
}
|
||||
}
|
||||
var int-256/eax: int <- copy 0x100
|
||||
var scaling-factor/xmm1: float <- convert int-256
|
||||
var int-6/eax: int <- copy 6
|
||||
var six-f/xmm2: float <- convert int-6
|
||||
scaling-factor <- divide six-f
|
||||
hue-f <- multiply scaling-factor
|
||||
var hue/eax: int <- convert hue-f
|
||||
# if hue < 0, hue = 256 - hue
|
||||
compare hue, 0
|
||||
{
|
||||
break-if->=
|
||||
var tmp/ecx: int <- copy 0x100
|
||||
tmp <- subtract hue
|
||||
hue <- copy tmp
|
||||
}
|
||||
return hue, saturation, luminance
|
||||
}
|
||||
|
||||
fn test-hsl-black {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0, 0, 0
|
||||
check-ints-equal h, 0, "F - test-hsl-black/hue"
|
||||
check-ints-equal s, 0, "F - test-hsl-black/saturation"
|
||||
check-ints-equal l, 0, "F - test-hsl-black/luminance"
|
||||
}
|
||||
|
||||
fn test-hsl-white {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0xff, 0xff, 0xff
|
||||
check-ints-equal h, 0, "F - test-hsl-white/hue"
|
||||
check-ints-equal s, 0, "F - test-hsl-white/saturation"
|
||||
check-ints-equal l, 0xff, "F - test-hsl-white/luminance"
|
||||
}
|
||||
|
||||
fn test-hsl-grey {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0x30, 0x30, 0x30
|
||||
check-ints-equal h, 0, "F - test-hsl-grey/hue"
|
||||
check-ints-equal s, 0, "F - test-hsl-grey/saturation"
|
||||
check-ints-equal l, 0x30, "F - test-hsl-grey/luminance"
|
||||
}
|
||||
|
||||
# red hues: 0-0x54
|
||||
fn test-hsl-slightly-red {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0xff, 0xfe, 0xfe
|
||||
check-ints-equal h, 0, "F - test-hsl-slightly-red/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-slightly-red/saturation"
|
||||
check-ints-equal l, 0xfe, "F - test-hsl-slightly-red/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
fn test-hsl-extremely-red {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0xff, 0, 0
|
||||
check-ints-equal h, 0, "F - test-hsl-extremely-red/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-extremely-red/saturation"
|
||||
check-ints-equal l, 0x7f, "F - test-hsl-extremely-red/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
# green hues: 0x55-0xaa
|
||||
fn test-hsl-slightly-green {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0xfe, 0xff, 0xfe
|
||||
check-ints-equal h, 0x55, "F - test-hsl-slightly-green/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-slightly-green/saturation"
|
||||
check-ints-equal l, 0xfe, "F - test-hsl-slightly-green/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
fn test-hsl-extremely-green {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0, 0xff, 0
|
||||
check-ints-equal h, 0x55, "F - test-hsl-extremely-green/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-extremely-green/saturation"
|
||||
check-ints-equal l, 0x7f, "F - test-hsl-extremely-green/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
# blue hues: 0xab-0xff
|
||||
fn test-hsl-slightly-blue {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0xfe, 0xfe, 0xff
|
||||
check-ints-equal h, 0xab, "F - test-hsl-slightly-blue/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-slightly-blue/saturation"
|
||||
check-ints-equal l, 0xfe, "F - test-hsl-slightly-blue/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
fn test-hsl-extremely-blue {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0, 0, 0xff
|
||||
check-ints-equal h, 0xab, "F - test-hsl-extremely-blue/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-extremely-blue/saturation"
|
||||
check-ints-equal l, 0x7f, "F - test-hsl-extremely-blue/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
# cyan: 0x7f
|
||||
|
||||
fn test-hsl-cyan {
|
||||
var h/ecx: int <- copy 0
|
||||
var s/edx: int <- copy 0
|
||||
var l/ebx: int <- copy 0
|
||||
h, s, l <- hsl 0, 0xff, 0xff
|
||||
check-ints-equal h, 0x80, "F - test-hsl-cyan/hue"
|
||||
check-ints-equal s, 0xff, "F - test-hsl-cyan/saturation"
|
||||
check-ints-equal l, 0x7f, "F - test-hsl-cyan/luminance" # TODO: should round up
|
||||
}
|
||||
|
||||
###
|
||||
|
||||
fn maximum a: int, b: int -> _/eax: int {
|
||||
var a2/eax: int <- copy a
|
||||
compare a2, b
|
||||
{
|
||||
break-if-<
|
||||
return a
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
fn minimum a: int, b: int -> _/eax: int {
|
||||
var a2/eax: int <- copy a
|
||||
compare a2, b
|
||||
{
|
||||
break-if->
|
||||
return a
|
||||
}
|
||||
return b
|
||||
}
|
||||
Loading…
Reference in New Issue