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;
}

Also see

hsl2rgb

Comments

Everyone can add his comments about his experiences with this function here. Tips for using it are welcome, too.