Files
maszyna/shaders/conversion.glsl
2020-08-12 20:57:57 +02:00

109 lines
2.3 KiB
GLSL

vec3 rgb2yuv(vec3 input)
{
return
clamp(
vec3(
(0.257 * input.r) + (0.504 * input.g) + (0.098 * input.b) + 0.0625,
-(0.148 * input.r) - (0.291 * input.g) + (0.439 * input.b) + 0.5,
(0.439 * input.r) - (0.368 * input.g) - (0.071 * input.b) + 0.5 ),
0.0, 1.0);
}
vec3 yuv2rgb(vec3 input)
{
input -= vec3(0.0625, 0.5, 0.5);
return
clamp(
vec3(
(1.164 * input.r) + (1.596 * input.b),
(1.164 * input.r) - (0.391 * input.g) - (0.813 * input.b),
(1.164 * input.r) + (2.018 * input.g) ),
0.0, 1.0);
}
vec3 rgb2hsl( vec3 col )
{
float red = col.r;
float green = col.g;
float blue = col.b;
float minc = min( col.r, min( col.g, col.b ));
float maxc = max( col.r, max( col.g, col.b ));
float delta = maxc - minc;
float lum = (minc + maxc) * 0.5;
float sat = 0.0;
float hue = 0.0;
if (lum > 0.0 && lum < 1.0) {
float mul = (lum < 0.5) ? (lum) : (1.0-lum);
sat = delta / (mul * 2.0);
}
vec3 masks = vec3(
(maxc == red && maxc != green) ? 1.0 : 0.0,
(maxc == green && maxc != blue) ? 1.0 : 0.0,
(maxc == blue && maxc != red) ? 1.0 : 0.0
);
vec3 adds = vec3(
((green - blue ) / delta),
2.0 + ((blue - red ) / delta),
4.0 + ((red - green) / delta)
);
float deltaGtz = (delta > 0.0) ? 1.0 : 0.0;
hue += dot( adds, masks );
hue *= deltaGtz;
hue /= 6.0;
if (hue < 0.0)
hue += 1.0;
return vec3( hue, sat, lum );
}
vec3 hsl2rgb( vec3 col )
{
const float onethird = 1.0 / 3.0;
const float twothird = 2.0 / 3.0;
const float rcpsixth = 6.0;
float hue = col.x;
float sat = col.y;
float lum = col.z;
vec3 xt = vec3(
rcpsixth * (hue - twothird),
0.0,
rcpsixth * (1.0 - hue)
);
if (hue < twothird) {
xt.r = 0.0;
xt.g = rcpsixth * (twothird - hue);
xt.b = rcpsixth * (hue - onethird);
}
if (hue < onethird) {
xt.r = rcpsixth * (onethird - hue);
xt.g = rcpsixth * hue;
xt.b = 0.0;
}
xt = min( xt, 1.0 );
float sat2 = 2.0 * sat;
float satinv = 1.0 - sat;
float luminv = 1.0 - lum;
float lum2m1 = (2.0 * lum) - 1.0;
vec3 ct = (sat2 * xt) + satinv;
vec3 rgb;
if (lum >= 0.5) { rgb = (luminv * ct) + lum2m1; }
else { rgb = lum * ct; }
return rgb;
}