Computer Science 252
Problem Solving with Java
Spring 2014, The College of Saint Rose
SwingFallingSnow Demo
A working demo of SwingFallingSnow will appear below. Click inside the applet to interact with it.
SwingFallingSnow BlueJ Project
Click here to download a BlueJ project for SwingFallingSnow.
SwingFallingSnow Source Code
The Java source code for SwingFallingSnow is below. Click on a file name to download it.
import objectdraw.*;
import java.awt.*;
import javax.swing.JSlider;
/*
*
* Example FallingSnow: the snowflakes that fall, this time with
* x speeds controlled by a slider that was passed in and saved.
*
* Jim Teresco, Siena College, CSIS 120, Spring 2011
* The College of Saint Rose, Fall 2013, Fall 2014
* Based on example from CSCI 134, Williams College
*
* $Id: FallingSnow.java 2452 2014-10-13 15:59:20Z terescoj $
*/
public class FallingSnow extends ActiveObject {
// delay between snow motions
private static final int DELAY_TIME = 33;
private DrawingCanvas canvas;
// speed of fall
private double ySpeed;
// the snowflake
private VisibleImage snow;
// the wind
private JSlider wind;
// initialize the instance variables and start the active object
public FallingSnow(DrawingCanvas aCanvas, Image aSnowPic, JSlider w,
double x, double aSpeed) {
canvas = aCanvas;
ySpeed = aSpeed;
wind = w;
snow = new VisibleImage(aSnowPic, 0, 0, canvas);
snow.move(x, - snow.getHeight());
start();
}
public void run() {
// as long as the snow is still on the screen
// move it and pause
while (snow.getY() < canvas.getHeight()) {
pause(DELAY_TIME);
// get the x speed from the JSlider
snow.move(wind.getValue(),ySpeed);
}
snow.removeFromCanvas();
}
}
import objectdraw.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JSlider;
/*
*
* Example SwingFallingSnow: the main class that creates clouds, which in turn
* create falling snowflakes.
*
* This one uses Java Swing components to control cloud creation and
* the wind speed and direction
*
* Jim Teresco, The College of Saint Rose, Fall 2014
*
* $Id: Snow.java 2452 2014-10-13 15:59:20Z terescoj $
*/
// Program which creates clouds which create snow when the user pressed the
// button
public class Snow extends WindowController implements ActionListener {
// constants for the moon size and location
private static final double MOON_INSET = 50;
private static final int MOON_SIZE = 70;
// sizes and locations for the bricks
private static final double BRICK_LINE = 40; // from bottom
private static final double BRICK_HEIGHT = 12;
private static final double BRICK_WIDTH = 30;
private static final double BRICK_SPACING = 3;
// colors of the sky, mortar, and brick
private final Color NIGHTSKY = new Color(50, 50, 100);
private final Color MORTAR = new Color(200, 200, 200);
private final Color BRICKRED = new Color(150, 40, 40);
// allowed wind speeds
private static final int MAX_WIND = 5;
// image of the snow
private Image snowPic;
// our wind controller
private JSlider windSlider;
public void begin() {
// we'll get the Swing components there first
Container contentPane = getContentPane();
// a panel to go on the bottom of the window
JPanel southPanel = new JPanel();
// a button to create a new cloud, add to panel, set up listener
JButton cloudButton = new JButton("Create Cloud");
southPanel.add(cloudButton);
cloudButton.addActionListener(this);
// a slider that will control the wind
windSlider = new JSlider(JSlider.HORIZONTAL, -MAX_WIND, MAX_WIND, 0);
southPanel.add(windSlider);
// add the panel to the south
contentPane.add(southPanel, BorderLayout.SOUTH);
contentPane.validate();
// now start drawing things on our canvas
// where to draw next brick
double brickPosition;
// get leaf picture
snowPic = getImage("snow.gif");
// draw solid sky, mortar, and moon
new FilledRect(0, 0, canvas.getWidth(), canvas.getHeight() - BRICK_LINE, canvas).setColor(NIGHTSKY);
new FilledRect(0, canvas.getHeight() - BRICK_LINE, canvas.getWidth(),
canvas.getHeight(),
canvas).setColor(MORTAR);
new FilledOval(MOON_INSET,MOON_INSET,MOON_SIZE,MOON_SIZE,
canvas).setColor(Color.white);
// add the bricks
brickPosition = 0;
while ( brickPosition < canvas.getWidth() ) {
new FilledRect(brickPosition, canvas.getHeight() - BRICK_LINE,
BRICK_WIDTH, BRICK_HEIGHT,
canvas).setColor(BRICKRED);
brickPosition = brickPosition + BRICK_WIDTH + BRICK_SPACING;
}
}
public void actionPerformed(ActionEvent e) {
// make a new snow-dropping cloud when the user presses
// the (only) button
new Cloud(snowPic, windSlider, canvas);
}
}
import objectdraw.*;
import java.awt.*;
import java.util.Random;
import javax.swing.JSlider;
/*
*
* Example FallingSnow: the cloud class which is responsible for
* creating a bunch of snowflakes, this one passing through a
* JSlider to control "wind" to the snowflakes when created.
*
* Jim Teresco, Siena College, CSIS 120, Spring 2011
* The College of Saint Rose, Fall 2013, Fall 2014
* Based on example from CSCI 134, Williams College
*
* $Id: Cloud.java 2452 2014-10-13 15:59:20Z terescoj $
*/
public class Cloud extends ActiveObject {
// total number of snowflakes
private static final int MAX_SNOW = 150;
// time between flakes
private static final int FLAKE_INTERVAL = 900;
// the canvas
private DrawingCanvas canvas;
// picture of a snowflake
private Image snowPic;
// used to generate random speeds and positions for snowflakes
private Random snowGen;
// our Wind generator
private JSlider wind;
public Cloud(Image aSnowPic, JSlider wind, DrawingCanvas aCanvas) {
// save the parameters for the "run" method
canvas = aCanvas;
snowPic = aSnowPic;
this.wind = wind;
snowGen = new Random();
start();
}
public void run()
{
int snowCount= 0;
// continue creating snow until the maximum amount
// has been created
while (snowCount < MAX_SNOW ) {
snowCount = snowCount + 1;
new FallingSnow(canvas, snowPic, wind,
snowGen.nextInt((int)canvas.getWidth()), // x coordinate
snowGen.nextDouble()*2+2); // y speed
pause(FLAKE_INTERVAL);
}
}
}