/*
  In this example, the user can draw an ellipse by selecting the center
  and then dragging the mouse to designate a corner of the bounding box
*/

int cx,cy;

// This function is executed only once, at the very beginning
void setup() {
  size(500,400);
  background(255);
  fill(128, 128, 255);
}


// This function is repeatedly call in an implicit loop.
// A single call is responsible for drawing a single frame.
void draw() {
}

void mousePressed() {
  cx = mouseX;
  cy = mouseY;
}

void mouseDragged() {
  background(255);
  noFill();
  int w = 2*abs(mouseX-cx);
  int h = 2*abs(mouseY-cy);
  ellipse(cx,cy,w,h);
}

void mouseReleased() {
  background(255);
  fill(128,128,255);
  int w = 2*abs(mouseX-cx);
  int h = 2*abs(mouseY-cy);
  ellipse(cx,cy,w,h);  
}