gistfile1.pde

int square = 20;
int dw, dh, hw, hh, hs;

void setup() {
  size(500, 500);
  
  dw = width / square / 2;
  dh = height / square / 2;
  hw = width / 2;
  hh = height / 2;
  hs = square / 2; 
  
  strokeWeight(2);
  noFill();
}

void draw() {
    background(255);
  
    int i, j;
    int x, y;
    float a, b;
    float r = frameCount / -20.0;
    float mx = hw - cos(r) * 100;
    float my = hh - sin(r) * 100;
    
    rect(mx, my, 1, 1);
    
    for(i = 1; i < dw - 1; i++) {
      
      beginShape();
      
      for(j = 4; j < dh - 4; j++) {
        x = square + i * 2 * square;
        y = square + j * 2 * square;
        r = atan2(my - y, mx - x);
        a = cos(r) * square; // * (i - dw / 2);
        b = sin(r) * square; // * (j - dw / 2);
        
        //rect(x, y, square, square);
        //rect(x + a, y + b, square, square);
        
        //line(x, y, x + a, y + b);
        //line(x, y + square, x + a, y + b + square);
        //line(x + square, y, x + square + a, y + b);
        //line(x + square, y + square, x + square + a, y + square + b);
        
        vertex(x + a, y + b);
        
        /*
        beginShape();
        vertex(x, y);
        vertex(x + a, y + b);
        vertex(x + a + square, y + b);
        vertex(x + square, y);
        vertex(x + square, y + square);
        vertex(x + a + square, y + b + square);
        vertex(x + a, y + b + square);
        vertex(x, y + square);
        endShape(CLOSE);
        */
        
      }
      
      endShape();
    }
    
    //saveFrame("frame-######.png");
}