// strange attractor recipe from Mr Clifford A Pickover
// Page 163 of Computers, Pattern, Chaos and Beauty

float rWidth=4.0, rHeight=4.0, pixelSize;
int centreX, centreY;
int sWidth=650, sHeight=650;
float rxMax = rWidth/2, rxMin = -rxMax, ryMax = rHeight/2, ryMin=-ryMax;


int[][] xy;

float xxmin, xxmax, yymin, yymax, pres;
float a,b,c,d,e;

float xinc, yinc;
float sc;
 float x,y,z;
 int j;
 boolean flag=false;
 boolean inverse=false;
 int blank;


void setup()
{
  size(sWidth, sHeight);

 if(inverse){ blank = 0; }else{ blank=255; } 
  int maxX = sWidth-1;
  int maxY = sHeight-1;
  
  xy = new int[sWidth][sHeight];
  
  pixelSize = max(rWidth/maxX, rHeight/maxY);
  centreX = maxX/2; 
  centreY = maxY/2;
   sc=2; 


 xxmin = -2;
 xxmax =2;
 yymin = -2;
 yymax = 2;


  a=2.24; b =0.43; c = -0.63; d=-2.43; e = 1.0;
  j=1; 

 x=0; y=0; z=0;
 background(blank);
 emptyArray();

}

void draw(){
if(!flag){
  iterate(true);
  j++;
  }else{flag=false;}
  //drawArray();
}

void iterate(boolean drawing){
  for(int i=0; i < 100000; i++){
   float xx = sin(a*y) - z * cos(b*x);
     float yy = z * sin(c*x) - cos(d*y);
     float zz = e * sin(x);
     
     x =xx; y = yy; z = zz;
     if(xx < xxmax & xx > xxmin & yy < yymax && yy > yymin){ 
       // saturate the canvas on each visit, 
       // rather than just plonking a point on
       int xv = iX(xx);
       int yv = iY(yy);
         if(inverse){
            if(xy[ xv ][ yv ]<255){ xy[xv][yv]++; }
         }else{
            if(xy[ xv ][ yv ]>0){ xy[xv][yv]--; }
         }
       
        if(drawing){
          stroke(xy[xv][yv]);
          point(xv,yv);
        }
           
    }
   }
}

void mouseReleased(){
  
  j=1; 
  int yVal = mouseY;
  print((float)yVal/650.0);
  e=(float)yVal/200.0;
  c=-(float)mouseX/650.0;
   x=0; y=0; z=0;
    emptyArray();
   background(blank);
   flag=true;

}

void emptyArray(){

 for(int s =0; s<sWidth; s++){
   for(int t=0; t < sHeight; t++){
      xy[s][t]=blank;
   }
 }
}


void drawArray(){
 for(int s=0; s<sWidth; s++){
   for(int t=0; t < sHeight; t++){
     stroke(xy[s][t]);
     point(s,t);
   }
 }
}



int iX(float x){  return int(centreX + x/pixelSize); }
int iY(float y){ return int(centreY - y/pixelSize); }
float fx(int X){ return ( X- centreX) * pixelSize; }
float fy(int Y){ return (centreY - Y) * pixelSize; }