Computer Science 202
Introduction to Programming

Fall 2013, The College of Saint Rose

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Spirograph Demo

A working demo of Spirograph will appear below. Click inside the applet to interact with it.

Spirograph BlueJ Project

Click here to download a BlueJ project for Spirograph.

Spirograph Source Code

The Java source code for Spirograph is below. Click on a file name to download it.

Spirograph.java

import objectdraw.*;

/*
 * This program is a "Spirograph".  When the mouse is pressed then dragged,
 * a series of lines are drawn from the press point to the current location.
 *
 * Jim Teresco, Siena College, CSCI 120, Spring 2011
 * The College of Saint Rose, Fall 2013
 * Based on similar example from Williams College CS 134.
 *
 * $Id: Spirograph.java 1495 2011-01-20 03:51:59Z terescoj $
 */
public class Spirograph extends WindowController {

    // First coordinate of a line segment
    private Location linesStart;

    /*
     * When the mouse is pressed, save the press point to be used as
     * the first endpoint of the lines drawn during dragging
     */
    public void onMousePress(Location point) {
        linesStart = point;
    } 

    /*
     * As the user is dragging, draw a line from
     * initial point where mouse pressed to current point.
     */
    public void onMouseDrag(Location point) {
        new Line(linesStart, point, canvas);
    }
}