palette.go RawHistoryFolder

1package layout
2
3var cube = [6]uint8{0, 95, 135, 175, 215, 255}
4
5// palette maps an xterm 256-color index to RGB. The first 16 come from the
6// theme; the color cube and the gray ramp are fixed, as in any terminal.
7func palette(i int, base *[16][3]uint8) [3]uint8 {
8	switch {
9	case i < 0:
10		return [3]uint8{}
11	case i < 16:
12		return base[i]
13	case i < 232:
14		i -= 16
15		return [3]uint8{cube[i/36], cube[i/6%6], cube[i%6]}
16	case i < 256:
17		v := uint8(8 + (i-232)*10)
18		return [3]uint8{v, v, v}
19	}
20	return [3]uint8{0xff, 0xff, 0xff}
21}