rgb2hsl

Syntax

int rgb2hsl(int r, int g, int b, int z)

Arguments

r
Red value
g
Green value
b
Blue value
z
Determines which value is returned. z=0 for H (Hue), z=1 for S (Saturation), z=2 for L (Lightness)

Return

Returns the H, S or L value from 0 to 255 depending on the value of z

Description

Lets you convert RGB values to HSL values.

Example

%ffp

ctl(0): "Adjust H", Range=(-255,255), val=0
ctl(1): "Adjust S", Range=(-255,255), val=0
ctl(2): "Adjust L", Range=(-255,255), val=0

ForEveryTile:{

  int r,g,b,h,s,l;

  for (y= y_start; y < y_end; y++) {

    if (updateProgress(y, y_end)) abort();

    for (x = x_start; x < x_end; x++) {
				
      r = src(x,y,0);
      g = src(x,y,1);
      b = src(x,y,2);

      h = rgb2hsl (r,g,b,0);
      s = rgb2hsl (r,g,b,1); 
      l = rgb2hsl (r,g,b,2); 
			
      // Do the HSL adjustment
      h = h + ctl(0);
      s = s + ctl(1);
      l = l + ctl(2);

      pset( x, y, 0, hsl2rgb (h,s,l,0) );
      pset( x, y, 1, hsl2rgb (h,s,l,1) );
      pset( x, y, 2, hsl2rgb (h,s,l,2) );
    }
  }

  return true;
}

See Also

hsl2rgb