Skip to content

Instantly share code, notes, and snippets.

@yiwenl

yiwenl/hsv2rgb

Last active October 24, 2024 01:30
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save yiwenl/745bfea7f04c456e0101 to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save yiwenl/745bfea7f04c456e0101 to your computer and use it in GitHub Desktop.
Download ZIP

Revisions

  1. yiwenl revised this gist Nov 24, 2015. 1 changed file with 6 additions and 0 deletions.
    6 changes: 6 additions & 0 deletions hsv2rgb
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,6 @@
    vec3 hsv2rgb(vec3 c)
    {
    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
    }
  2. yiwenl revised this gist Nov 24, 2015. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion rgbToHSL
    View file
    Original file line number Diff line number Diff line change
    @@ -1,4 +1,4 @@
    vec3 RGBToHSL(vec3 color) {
    vec3 rgb2hsl(vec3 color) {
    vec3 hsl; // init to 0 to avoid warnings ? (and reverse if + remove first part)

    float fmin = min(min(color.r, color.g), color.b); //Min. value of RGB
  3. yiwenl created this gist Nov 24, 2015.
    39 changes: 39 additions & 0 deletions rgbToHSL
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,39 @@
    vec3 RGBToHSL(vec3 color) {
    vec3 hsl; // init to 0 to avoid warnings ? (and reverse if + remove first part)

    float fmin = min(min(color.r, color.g), color.b); //Min. value of RGB
    float fmax = max(max(color.r, color.g), color.b); //Max. value of RGB
    float delta = fmax - fmin; //Delta RGB value

    hsl.z = (fmax + fmin) / 2.0; // Luminance

    if (delta == 0.0) //This is a gray, no chroma...
    {
    hsl.x = 0.0; // Hue
    hsl.y = 0.0; // Saturation
    } else //Chromatic data...
    {
    if (hsl.z < 0.5)
    hsl.y = delta / (fmax + fmin); // Saturation
    else
    hsl.y = delta / (2.0 - fmax - fmin); // Saturation

    float deltaR = (((fmax - color.r) / 6.0) + (delta / 2.0)) / delta;
    float deltaG = (((fmax - color.g) / 6.0) + (delta / 2.0)) / delta;
    float deltaB = (((fmax - color.b) / 6.0) + (delta / 2.0)) / delta;

    if (color.r == fmax)
    hsl.x = deltaB - deltaG; // Hue
    else if (color.g == fmax)
    hsl.x = (1.0 / 3.0) + deltaR - deltaB; // Hue
    else if (color.b == fmax)
    hsl.x = (2.0 / 3.0) + deltaG - deltaR; // Hue

    if (hsl.x < 0.0)
    hsl.x += 1.0; // Hue
    else if (hsl.x > 1.0)
    hsl.x -= 1.0; // Hue
    }

    return hsl;
    }
    22 changes: 22 additions & 0 deletions rgbToHSV
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,22 @@
    vec3 rgb2hsv(vec3 rgb) {
    float Cmax = max(rgb.r, max(rgb.g, rgb.b));
    float Cmin = min(rgb.r, min(rgb.g, rgb.b));
    float delta = Cmax - Cmin;

    vec3 hsv = vec3(0., 0., Cmax);

    if (Cmax > Cmin) {
    hsv.y = delta / Cmax;

    if (rgb.r == Cmax)
    hsv.x = (rgb.g - rgb.b) / delta;
    else {
    if (rgb.g == Cmax)
    hsv.x = 2. + (rgb.b - rgb.r) / delta;
    else
    hsv.x = 4. + (rgb.r - rgb.g) / delta;
    }
    hsv.x = fract(hsv.x / 6.);
    }
    return hsv;
    }