//*** This code is copyright 2003 by Gavin Kistner, gavin@refinery.com
//*** It is covered under the license viewable at http://phrogz.net/JS/_ReuseLicense.txt
//*** Reuse or modification is free provided you abide by the terms of that license.
//*** (Including the first two lines above in your source code satisfies the conditions.)


function RGB2HSV(r,g,b){
	//***Returns an hsv object from RGB values
	//***The r (red), g (green), and b (blue) should be values in the range 0 to 1
	//***The returned object has .h, .s, and .v properties.
	//***h is a value from 0 to 360
	//***s and v are values between 0 and 1
		var h,s,v,max,min,d;

		r=r>1?1:r<0?0:r;
		g=g>1?1:g<0?0:g;
		b=b>1?1:b<0?0:b;

		max=min=r;
		if (g>max) max=g; if (g<min) min=g;
		if (b>max) max=b; if (b<min) min=b;
		d=max-min;
		v=max;
		s=(max>0)?d/max:0;

		if (s==0) h=0;
		else {
			h=60*((r==max)?(g-b)/d:((g==max)?2+(b-r)/d:4+(r-g)/d));
			if (h<0) h+=360;
		}
		return {h:h,s:s,v:v}
}

function HSV2RGB(h,s,v){
	//***Returns an rgb object from HSV values
	//***h (hue) should be a value from 0 to 360
	//***s (saturation) and v (value) should be a value between 0 and 1
	//***The .r, .g, and .b properties of the returned object are all in the range 0 to 1
	var r,g,b,i,f,p,q,t;
	while (h<0) h+=360;
	h%=360;
	s=s>1?1:s<0?0:s;
	v=v>1?1:v<0?0:v;

	if (s==0) r=g=b=v;
	else {
		h/=60;
		f=h-(i=Math.floor(h));
		p=v*(1-s);
		q=v*(1-s*f);
		t=v*(1-s*(1-f));
		switch (i) {
			case 0:r=v; g=t; b=p; break;
			case 1:r=q; g=v; b=p; break;
			case 2:r=p; g=v; b=t; break;
			case 3:r=p; g=q; b=v; break;
			case 4:r=t; g=p; b=v; break;
			case 5:r=v; g=p; b=q; break;
		}
	}
	return {r:r,g:g,b:b};
}

function Hex2Dec(hex){
	//*** Turns a hexadecimal number into an integer
	return parseInt(hex,16);
}


function Dec2Hex(dec,padTo){
	//*** Turns a decimal number into hexadecimal
	//*** If padTo is specified (optional) the result is padded with leading zeros to the specified number of characters
	var h=Math.round(dec).toString(16).toLowerCase();
	if (padTo && h.length<padTo) h=(Math.pow(10,padTo-h.length)+h).substr(1);
	return h;
}


function HTMLfromRGB(rgb){
	//*** Returns an HTML string like '#f3ca12' from an 'rgb' object
	return "#"+Dec2Hex(rgb.r*255,2)+Dec2Hex(rgb.g*255,2)+Dec2Hex(rgb.b*255,2);
}


function RGBfromHTML(htmlrgb){
	//*** Returns an rgb object from an HTML string like '#f3ca12' or '#ccc' (leading # is optional)
	if (htmlrgb.length==7 || htmlrgb.length==4) htmlrgb=htmlrgb.substr(1);
	if (htmlrgb.length==3) htmlrgb=htmlrgb.charAt(0)+htmlrgb.charAt(0)+htmlrgb.charAt(1)+htmlrgb.charAt(1)+htmlrgb.charAt(2)+htmlrgb.charAt(2);
	if (htmlrgb.length!=6) return null;
	return {r:Hex2Dec(htmlrgb.substr(0,2))/255,g:Hex2Dec(htmlrgb.substr(2,2))/255,b:Hex2Dec(htmlrgb.substr(4,2))/255}
}