File: resources/color_functions.js

function baseConverter (number,ob,nb) {
	number = number + "";
	number = number.toUpperCase();
	var list = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	var dec = 0;
	for (var i = 0; i <=  number.length; i++) {
		dec += (list.indexOf(number.charAt(i))) * (Math.pow(ob , (number.length - i - 1)));
	}
	number = "";
	var magnitude = Math.floor((Math.log(dec))/(Math.log(nb)));
	for (var i = magnitude; i >= 0; i--) {
		var amount = Math.floor(dec/Math.pow(nb,i));
		number = number + list.charAt(amount); 
		dec -= amount*(Math.pow(nb,i));
	}
	if(number.length==0)number=0;
	return number;
}

// Converts a RGB color to HSV
function toHSV(rgbColor){
	rgbColor = rgbColor.replace('#','');		
	
	red = baseConverter(rgbColor.substr(0,2),16,10);
	green = baseConverter(rgbColor.substr(2,2),16,10);
	blue = baseConverter(rgbColor.substr(4,2),16,10);
	if(red.length==0)red=0;
	if(green.length==0)green=0;
	if(blue.length==0)blue=0;
	red = red/255;
	green = green/255;
	blue = blue/255;
	
	maxValue = Math.max(red,green,blue);
	minValue = Math.min(red,green,blue);
	
	var hue = 0;
	
	if(maxValue==minValue){
		hue = 0;
		saturation=0;
	}else{
		if(red == maxValue){
			hue = (green - blue) / (maxValue-minValue)/1;	
		}else if(green == maxValue){
			hue = 2 + (blue - red)/1 / (maxValue-minValue)/1;	
		}else if(blue == maxValue){
			hue = 4 + (red - green) / (maxValue-minValue)/1;	
		}
		saturation = (maxValue-minValue) / maxValue;
	}
	hue = hue * 60; 
	valueBrightness = maxValue;
	
	if(valueBrightness/1<0.5){
		//saturation = (maxValue - minValue) / (maxValue + minValue);
	}
	if(valueBrightness/1>= 0.5){
		//saturation = (maxValue - minValue) / (2 - maxValue - minValue);
	}	
		
	
	returnArray = [hue,saturation,valueBrightness];
	return returnArray;
}

function toRgb(hue,saturation,valueBrightness){
	Hi = Math.floor(hue / 60);
	if(hue==360)Hi=0;
	f = hue/60 - Hi;
	p = (valueBrightness * (1- saturation)).toPrecision(2);
	q = (valueBrightness * (1 - (f * saturation))).toPrecision(2);
	t = (valueBrightness * (1 - ((1-f)*saturation))).toPrecision(2);

	switch(Hi){
		case 0:
			red = valueBrightness;
			green = t;
			blue = p;				
			break;
		case 1: 
			red = q;
			green = valueBrightness;
			blue = p;
			break;
		case 2: 
			red = q;
			green = valueBrightness;
			blue = t;
			break;
		case 3: 
			red = p;
			green = q;;
			blue = valueBrightness;
			break;
		case 4:
			red = t;
			green = p;
			blue = valueBrightness;
			break;
		case 5:
			red = valueBrightness;
			green = p;
			blue = q;
			break;
	}
	
	if(saturation==0){
		red = valueBrightness;
		green = valueBrightness;
		blue = valueBrightness;		
	}
	
	red*=255;
	green*=255;
	blue*=255;

	red = Math.round(red);
	green = Math.round(green);
	blue = Math.round(blue);	
	
	red = baseConverter(red,10,16);
	green = baseConverter(green,10,16);
	blue = baseConverter(blue,10,16);
	
	red = red + "";
	green = green + "";
	blue = blue + "";

	while(red.length<2){
		red = "0" + red;
	}	
	while(green.length<2){
		green = "0" + green;
	}	
	while(blue.length<2){
		blue = "0" + "" + blue;
	}
	rgbColor = "#" + red + "" + green + "" + blue;
	return rgbColor.toUpperCase();
}

function findColorByDegrees(rgbColor,degrees){
	rgbColor = rgbColor.replace('#','');
	myArray = toHSV(rgbColor);
	myArray[0]+=degrees;
	if(myArray[0]>=360)myArray[0]-=360;
	if(myArray[0]<0)myArray[0]+=360;	
	return toRgb(myArray[0],myArray[1],myArray[2]);
}

function findColorByBrightness(rgbColor,brightness){
	
	rgbColor = rgbColor.replace('#','');
	myArray = toHSV(rgbColor);
	
	myArray[2]+=brightness/100;
	if(myArray[2]>1)myArray[2]=1;
	if(myArray[2]<0)myArray[2]=0;	
	
	myArray[1]+=brightness/100;
	if(myArray[1]>1)myArray[1]=1;
	if(myArray[1]<0)myArray[1]=0;		
	
	return toRgb(myArray[0],myArray[1],myArray[2]);	
	
}