/* built with Studio Sketchpad: 
 *   https://sketchpad.cc
 * 
 * observe the evolution of this sketch: 
 *   https://studio.sketchpad.cc/sp/pad/view/ro.kzfA5zpz2dL/rev.1114
 * 
 * authors: 
 *   erdely daniel
 *   
 *   daniel
 *   Janos Erdos Jr.
 *   
 *   dani

 * license (unless otherwise specified): 
 *   creative commons attribution-share alike 3.0 license.
 *   https://creativecommons.org/licenses/by-sa/3.0/ 
 */ 



void setup(){
    
    
    size(400,400);
}

void draw(){
    background(241,253,246);
     fill(70,84,170);
 
    //fill(202,26,88);

    noStroke();

    int s = 100;
 
    for(int i = -s; i < width+s; i+=s)
        for(int j = -s; j < height+s; j+=s){
    
        if( (i/s+j/s)%2==0 ) continue;

        PVector a = map(i, j);
        PVector b = map(i+s, j);
        PVector c = map(i, j+s);
        PVector d = map(i+s, j+s);
        
        beginShape();
        duplaspiral(a.x, a.y, b.x, b.y);
        duplaspiral(b.x, b.y, d.x, d.y);
        duplaspiral(d.x, d.y, c.x, c.y);
        duplaspiral(c.x, c.y, a.x, a.y);
        endShape();

        }
    }

PVector map(int x, int y){
    float d = dist(x,y, mouseX, mouseY), dd = sqrt(d)/2;
    
    if(d==0) return new PVector(x,y);
    
    return new PVector(x+(mouseX-x)/dd,y+(mouseY-y)/dd);
}


void duplaspiral(float x1, float y1, float x2, float y2){
    final float d = dist(x1,y1,x2,y2), a = atan2(x1-x2,y1-y2);
    final float phi = 2; //1.6180339887;
    final float A = 2.15, B=1;
 
   // beginShape();
    for(int radius = 0, d1 = d/phi, d1log=A*log(d1*B); radius < d1; radius+=1){
            float aa = a+A*log(radius*B)-d1log-PI;
            vertex(x1+sin(aa)*radius, y1+cos(aa)*radius);
    }
 
    for(int d1 = d-d/phi, d1log=A*log(d1*B), radius = d1; radius > 0; radius-=1){
            float aa = a+A*log(radius*B)-d1log;
            vertex(x2+sin(aa)*radius, y2+cos(aa)*radius);
    }
   // endShape(OPEN);
}