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import strutils
type
TColor = distinct int32
proc rgb(r, g, b: range[0..255]): TColor =
result = TColor(r or g shl 8 or b shl 16)
proc `$`(c: TColor): string =
result = "#" & toHex(int32(c), 6)
echo rgb(34, 55, 255)
when false:
type
TColor = distinct int32
TColorComponent = distinct int8
proc red(a: TColor): TColorComponent =
result = TColorComponent(int32(a) and 0xff'i32)
proc green(a: TColor): TColorComponent =
result = TColorComponent(int32(a) shr 8'i32 and 0xff'i32)
proc blue(a: TColor): TColorComponent =
result = TColorComponent(int32(a) shr 16'i32 and 0xff'i32)
proc rgb(r, g, b: range[0..255]): TColor =
result = TColor(r or g shl 8 or b shl 8)
proc `+!` (a, b: TColorComponent): TColorComponent =
## saturated arithmetic:
result = TColorComponent(min(ze(int8(a)) + ze(int8(b)), 255))
proc `+` (a, b: TColor): TColor =
## saturated arithmetic for colors makes sense, I think:
return rgb(red(a) +! red(b), green(a) +! green(b), blue(a) +! blue(b))
rgb(34, 55, 255)
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