/*
    Written by Alex Young

    Based on:
        http://astronomy.swin.edu.au/~pbourke/fractals/peterdejong/
*/

int width = 400, height = 400;
int iteration;
int colourRate = 1;

color defaultColour;
color colour;

float x = 0, y = 0, x2, y2;
int px, py;
float a = random_coord(), b = random_coord(), c = random_coord(), d = random_coord();

void setup()
{
    defaultColour = color(90, 60, 100);

    size(width, height);
    colorMode(RGB, 255);
    stroke(defaultColour);

    // Make a nice gradient    
    for (y = 0; y < height; y++)
    {
        stroke(red(defaultColour) - y, green(defaultColour) - y, blue(defaultColour) - y);
        line(0, y, width, y);
    }
}

void loop()
{
    //setup();
    
    for (iteration = 0; iteration < 2300; iteration++)
    {
    	if (mousePressed == true)
	    {
		    setup();
            a = random_coord();
            b = random_coord();
            c = random_coord();
            d = random_coord();
	    }
	                  
        x2 = cos(a * x) - sin(c * y);
        y2 = sin(b * x) - cos(d * y);

        // Convert to screen co-ords
        px = int((x2 + 1) * 80) + 80;
        py = int((y2 + 1) * 90) + 100;
 
        // Get the colour of the pixel
        colour = get(px, py);
        colour = color(red(colour) + colourRate, green(colour) + colourRate, blue(colour) + colourRate);
        set(px, py, colour);
        
        x = x2;
        y = y2;
     }
     
     a -= 0.001;
     b -= 0.001;
     c -= 0.001;
     d -= 0.001;
}

float random_coord()
{
    if (random(1) > 0.7)
    {
        return random(3)  * -1;
    }
    else
    {
        return random(3);
    }
}