func DrawBox(left, top, d, l int) {
var approxer string
switch currentComparer {
case 0:
approxer = "CIE76"
case 1:
approxer = "CIE94"
case 2:
approxer = "CIE2000"
}
r := d / 2
for y := 0; y < d; y++ {
for x := 0; x < d; x++ {
a := 100.0 * float64(x-r) / float64(r)
b := -100.0 * float64(y-r) / float64(r)
_, c := color.Approximate(color.LabColor{float64(l), a, b}, comparers[currentComparer])
//termbox.SetCell(x*2+left, y+top, ' ', background, termbox.Attribute(color))
//termbox.SetCell(x*2+left+1, y+top, ' ', background, termbox.Attribute(color))
fg := int(background)
if y == 1 || y == 2 || y == d-2 {
fgLab := color.XtermRGBPalette[c-17].Lab()
if l > 50 {
fgLab.L -= 50
//fgLab.L = 20
} else {
fgLab.L += 50
//fgLab.L = 70
}
_, fg = color.Approximate(fgLab, color.DeltaCIE2000{})
}
termbox.SetCell(x*2+left, y+top, ' ', termbox.Attribute(fg), termbox.Attribute(c))
termbox.SetCell(x*2+left+1, y+top, ' ', termbox.Attribute(fg), termbox.Attribute(c))
}
}
labLabel := "CIE L*a*b color space"
if len(labLabel)+4 < d*2 {
printString(left+2, top+1, labLabel)
printString(left+2, top+2, fmt.Sprintf("Lightness = %d%%", l))
}
//printString(left+2, top+4, fmt.Sprintln("Press Up/Down key for change"))
approxerLabel := fmt.Sprintf("Approximate by %s algorithm", approxer)
if len(approxerLabel)+4 <= d*2 {
printString(left+2, top+d-2, approxerLabel)
}
//printString(left+2, top+7, fmt.Sprintln("Press Left/Right key for change"))
}
func DrawCircle(left, top, r int, l float64) {
var ch [2]rune
point := func(xb, yb int) {
xl := xb / r
yl := yb / r
distance, color := color.Approximate(color.LChColor{l, math.Sqrt(float64(xl*xl) + float64(yl*yl)), 180.0 * math.Atan2(float64(xl), float64(yl))}, comparers[currentComparer])
//distance, color := color.Palette(color.LabColor{l, float64(xb * 120.0 / r), float64(-yb * 120.0 / r)}, color.DeltaCIE94{})
if distance < 50 {
ch[0] = ' '
ch[1] = ' '
} else {
//ch[0] = '¤'
//ch[1] = '¤'
ch[0] = '('
ch[1] = ')'
}
termbox.SetCell((xb+r)*2+left, yb+r+top, ch[0], termbox.Attribute(0), termbox.Attribute(color))
termbox.SetCell((xb+r)*2+left+1, yb+r+top, ch[1], termbox.Attribute(0), termbox.Attribute(color))
}
// алгоритм Брезенхэма
line := func(x, y1, y2 int) {
for yf := y1; yf <= y2; yf++ {
point(x, yf)
}
}
x := 0
y := r
d := 3 - 2*r
for x <= y {
line(x, -y, y)
line(-x, -y, y)
line(y, -x, x)
line(-y, -x, x)
if d < 0 {
d += 4*x + 6
} else {
d += 4*(x-y) + 10
y--
}
x++
}
}
