nulltrack's build of suckless terminal
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 

115 lines
2.8 KiB

// sixel.c (part of mintty)
// this function is derived from a part of graphics.c
// in Xterm pl#310 originally written by Ross Combs.
//
// Copyright 2013,2014 by Ross Combs
//
// All Rights Reserved
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
// Except as contained in this notice, the name(s) of the above copyright
// holders shall not be used in advertising or otherwise to promote the
// sale, use or other dealings in this Software without prior written
// authorization.
#define SIXEL_RGB(r, g, b) (((r) << 16) + ((g) << 8) + (b))
int
hls_to_rgb(int hue, int lum, int sat)
{
double hs = (hue + 240) % 360;
double hv = hs / 360.0;
double lv = lum / 100.0;
double sv = sat / 100.0;
double c, x, m, c2;
double r1, g1, b1;
int r, g, b;
int hpi;
if (sat == 0) {
r = g = b = lum * 255 / 100;
return SIXEL_RGB(r, g, b);
}
if ((c2 = ((2.0 * lv) - 1.0)) < 0.0) {
c2 = -c2;
}
c = (1.0 - c2) * sv;
hpi = (int) (hv * 6.0);
x = (hpi & 1) ? c : 0.0;
m = lv - 0.5 * c;
switch (hpi) {
case 0:
r1 = c;
g1 = x;
b1 = 0.0;
break;
case 1:
r1 = x;
g1 = c;
b1 = 0.0;
break;
case 2:
r1 = 0.0;
g1 = c;
b1 = x;
break;
case 3:
r1 = 0.0;
g1 = x;
b1 = c;
break;
case 4:
r1 = x;
g1 = 0.0;
b1 = c;
break;
case 5:
r1 = c;
g1 = 0.0;
b1 = x;
break;
default:
return SIXEL_RGB(255, 255, 255);
}
r = (int) ((r1 + m) * 100.0 + 0.5);
g = (int) ((g1 + m) * 100.0 + 0.5);
b = (int) ((b1 + m) * 100.0 + 0.5);
if (r < 0) {
r = 0;
} else if (r > 100) {
r = 100;
}
if (g < 0) {
g = 0;
} else if (g > 100) {
g = 100;
}
if (b < 0) {
b = 0;
} else if (b > 100) {
b = 100;
}
return SIXEL_RGB(r * 255 / 100, g * 255 / 100, b * 255 / 100);
}