# Return colors 'near' a given r/g/b value (expressed in hex)
# If we did this rigorously we'd need to implement cosines. So we won't.
#
# To build:
# $ ./translate colors.mu
#
# Example session:
# $ qemu-system-i386 code.img
# Enter 3 hex bytes for r, g, b (lowercase; no 0x prefix) separated by a single space> aa 0 aa
# 5
# This means only color 5 in the default palette is similar to #aa00aa.
fn main screen: (addr screen), keyboard: (addr keyboard), data-disk: (addr disk) {
var in-storage: (stream byte 0x10)
var in/esi: (addr stream byte) <- address in-storage
{
# print prompt
var x/eax: int <- draw-text-rightward screen, "Enter 3 hex bytes for r, g, b (lowercase; no 0x prefix) separated by a single space> ", 0x10/x, 0x80/xmax, 0x28/y, 3/fg/cyan, 0/bg
# read line from keyboard
clear-stream in
{
draw-cursor screen, 0x20/space
var key/eax: byte <- read-key keyboard
compare key, 0xa/newline
break-if-=
compare key, 0
loop-if-=
var key2/eax: int <- copy key
append-byte in, key2
var g/eax: grapheme <- copy key2
draw-grapheme-at-cursor screen, g, 0xf/fg, 0/bg
move-cursor-right 0
loop
}
clear-screen screen
# parse
var a/ecx: int <- copy 0
var b/edx: int <- copy 0
var c/ebx: int <- copy 0
# a, b, c = r, g, b
a, b, c <- parse in
#? set-cursor-position screen, 0x10/x, 0x1a/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, a, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, b, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, c, 7/fg, 0/bg
a, b, c <- hsl a, b, c
# return all colors in the same quadrant in h, s and l
print-nearby-colors screen, a, b, c
#
loop
}
}
# read exactly 3 words in a single line
# Each word consists of exactly 1 or 2 hex bytes. No hex prefix.
fn parse in: (addr stream byte) -> _/ecx: int, _/edx: int, _/ebx: int {
# read first byte of r
var tmp/eax: byte <- read-byte in
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
break-if-!=
abort "invalid byte 0 of r"
}
tmp <- fast-hex-digit-value tmp
var r/ecx: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x10/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, r, 7/fg, 0/bg
# read second byte of r
tmp <- read-byte in
{
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
}
break-if-=
r <- shift-left 4
tmp <- fast-hex-digit-value tmp
#? {
#? var foo/eax: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x11/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, foo, 7/fg, 0/bg
#? }
r <- add tmp
#? {
#? set-cursor-position 0/screen, 0x10/x, 0x12/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, r, 7/fg, 0/bg
#? }
tmp <- read-byte in # skip space
}
# read first byte of g
var tmp/eax: byte <- read-byte in
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
break-if-!=
abort "invalid byte 0 of g"
}
tmp <- fast-hex-digit-value tmp
var g/edx: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x13/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, g, 7/fg, 0/bg
# read second byte of g
tmp <- read-byte in
{
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
}
break-if-=
g <- shift-left 4
tmp <- fast-hex-digit-value tmp
#? {
#? var foo/eax: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x14/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, foo, 7/fg, 0/bg
#? }
g <- add tmp
#? {
#? set-cursor-position 0/screen, 0x10/x, 0x15/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, g, 7/fg, 0/bg
#? }
tmp <- read-byte in # skip space
}
# read first byte of b
var tmp/eax: byte <- read-byte in
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
break-if-!=
abort "invalid byte 0 of b"
}
tmp <- fast-hex-digit-value tmp
var b/ebx: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x16/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, b, 7/fg, 0/bg
# read second byte of b
{
{
var done?/eax: boolean <- stream-empty? in
compare done?, 0/false
}
break-if-!=
tmp <- read-byte in
{
var valid?/eax: boolean <- hex-digit? tmp
compare valid?, 0/false
}
break-if-=
b <- shift-left 4
tmp <- fast-hex-digit-value tmp
#? {
#? var foo/eax: int <- copy tmp
#? set-cursor-position 0/screen, 0x10/x, 0x17/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, foo, 7/fg, 0/bg
#? }
b <- add tmp
#? {
#? set-cursor-position 0/screen, 0x10/x, 0x18/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen 0/screen, b, 7/fg, 0/bg
#? }
}
return r, g, b
}
# no error checking
fn fast-hex-digit-value in: byte -> _/eax: byte {
var result/eax: byte <- copy in
compare result, 0x39
{
break-if->
result <- subtract 0x30/0
return result
}
result <- subtract 0x61/a
result <- add 0xa/10
return result
}
fn print-nearby-colors screen: (addr screen), h: int, s: int, l: int {
#? set-cursor-position screen, 0x10/x, 0x1c/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, h, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, s, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, l, 7/fg, 0/bg
# save just top 2 bits of each, so that we narrow down to 1/64th of the volume
shift-right h, 6
shift-right s, 6
shift-right l, 6
#? set-cursor-position screen, 0x10/x, 0x1/y
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, h, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, s, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, l, 7/fg, 0/bg
var a/ecx: int <- copy 0
var b/edx: int <- copy 0
var c/ebx: int <- copy 0
var color/eax: int <- copy 0
var y/esi: int <- copy 2
{
compare color, 0x100
break-if->=
a, b, c <- color-rgb color
a, b, c <- hsl a, b, c
a <- shift-right 6
b <- shift-right 6
c <- shift-right 6
{
compare a, h
break-if-!=
compare b, s
break-if-!=
compare c, l
break-if-!=
set-cursor-position screen, 0x10/x, y
draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen screen, color, 7/fg, 0/bg
set-cursor-position screen, 0x14/x, y
draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 0/fg, color
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, a, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, b, 7/fg, 0/bg
#? draw-text-wrapping-right-then-down-from-cursor-over-full-screen screen, " ", 7/fg, 0/bg
#? draw-int32-hex-wrapping-right-then-down-from-cursor-over-full-screen screen, c, 7/fg, 0/bg
y <- increment
}
color <- increment
loop
}
}