int NUM=1;

void setup(){
  size(400,300);
  stroke(128);
}

void draw(){
} 

void PDP(int N){
int i=1000;
boolean aij;
for (int x=0;x<50;x++){
    int j=0;
    for (int y=0;y<50;y++){
  
        //aij = (i-j)%2<1? true  : false;
        //miniruit
        
        //aij = (i-j)%4<2? true  : false;
        //aij = (i-j)%6<3? true  : false;
        //aij = (i-j)%8<4? true  : false;
        //aij = (i-j)%2<1? i%12<6  : j%12<6;
        //schuine strepen
    
        //aij = (i-j)%2<1? i%4<2  : j%4<2;
        //aij = (i-j)%2<1? i%6<3  : j%6<3;
        //aij = (i-j)%2<1? i%8<4  : j%8<4;
        //aij = (i-j)%2<1? i%12<6  : j%12<6;
          aij = (i-j)%2<1? i%(2*N)<N : j%(2*N)<N;
        //koksruiten 
       
        //aij = (i-j)%4<2? i%8<4  : j%8<4;
        //aij = (i-j)%6<3? i%12<6 : j%12<6;
        //aij = (i-j)%8<4? i%16<8 : j%16<8;
        //aij = (i-j)%12<6? i%24<12 : j%24<12;
        aij = (i-j)%(2*N)<N? i%(4*N)<(2*N) : j%(4*N)<(2*N);
        //pied de poules

        //aij = (i-j)%4<2? i%2<1  : j%2<1;
        //aij = (i-j)%8<4? i%2<1  : j%2<1;
        //aij = (i-j)%12<6? i%2<1 : j%2<1;
        //aij = (i-j)%16<8? i%2<1  : j%2<1;
        //visgraten van oplopende lengte
        
        //aij = (i-j)%8<4? i%4<2  : j%4<2;
        //aij = (i-j)%16<8? i%4<2  : j%4<2;
        //idem maar dubbele dikte
        
        //aij = (i-j)%12<6? i%6<3 : j%6<3;
        //idem driedubbele dikte
                
        //aij = i%4<2?  (i+j)%4 < 2 : (i-j)%4 < 2; 
        //aij = i%8<4?  (i+j)%4 < 2 : (i-j)%4 < 2; 
        //aij = i%16<8?  (i+j)%4 < 2 : (i-j)%4 < 2; 
        //aij = i%32<16?  (i+j)%4 < 2 : (i-j)%4 < 2; 
        //aij = i%(2*N)<N?  (i+j)%4 < 2 : (i-j)%4 < 2;
        //rechtvandraad visgraten van oplopende graatlengte
        
        fill(255*int(aij));
        rect(10*x,10*y,10,10);
        j++;
    }
    i++;
}
}

void mousePressed(){ 
}

void mkPrint(){
     PDP(NUM);
     String str = "VGR" + Integer.toString(NUM) + ".bmp";
     println("writing to "+str);   
     //saveFrame(str);  
}

void keyPressed() {
  if (key == CODED) {
    if (keyCode == UP) {
      print("setting N is ");println(++NUM);
      mkPrint();
    } else if (keyCode == DOWN && NUM>1) {
      print("setting N is ");println(--NUM);
      mkPrint();
    } 
  } else {
    if (key == ' '){
       mkPrint();
    }
  }
}