// mas964 ps2
// draw circles on mouse click that demonstrate repetition

import java.applet.*;
import java.awt.*;
import java.lang.Math;
import DoubleBufferApplet;

public class CircleRepetition extends DoubleBufferApplet {
  public boolean mouseDrag(Event e, int x, int y) {
    return mouseDown(e, x, y);
  }
  
  public boolean mouseDown(Event e, int x, int y) {
    Graphics g = imageBuffer.getGraphics();

    this.clearImageBuffer();
    g.setColor(this.getForeground());

    int maxNumCircles = 30;
    int circleSizeGradations = 10;
    int numCircles;
    int circleSize;
    float cellSize;

    // y coordinate controls the number of circles drawn
    numCircles = maxNumCircles * y / imageBufferSize.height + 2;
    if (imageBufferSize.width > imageBufferSize.height)
      cellSize = imageBufferSize.width / numCircles;
    else
      cellSize = imageBufferSize.height / numCircles;

    // x coordinate controls how big the circles are
    circleSize = (int)(cellSize * x / imageBufferSize.width) + 1;
    if (circleSize < 2)
      circleSize = 2;

    // System.out.println("numCircles " + numCircles + " circleSize " + circleSize);

    // now draw circles in a hexagonal pattern (some slop on both sides
    // to handle roundoff error)
    int i, j;
    for (i = -1; i < numCircles+4; i++) {
      for (j = -1; j < numCircles+4; j++) {
	if (i % 2 == 0)
	  g.fillOval(Math.round(i * cellSize), Math.round(j * cellSize),
		     circleSize, circleSize);
	else
	  g.fillOval(Math.round(i * cellSize),
		     Math.round(j * cellSize + cellSize/2),
		     circleSize, circleSize);
      }
    }
    
    repaint();
    return true;
  }
  
  public void init() {
    this.setBackground(Color.white);
    this.setForeground(Color.black);
    super.init();
  }
}