Project 3

Project 3 - Math 599: Java Programming

Assigned: July 10, 1997.
Due: July 17, 1997.

Ticker Tape: Write a Java Applet that displays a long text string as a "ticker tape". Try to make this as nice an object as you can. That is, make a TickerTape object which extends Component, or Canvas, or Label, as you wish, and which encapsulates all the necessary set-up and thread control.
Hint: To interact correctly with Layout Managers, make sure your object either inherits or overrides the methods minimumSize and preferredSize. The first should return a Dimension object with the smallest permissible screen size for the ticker tape; the second returns the Dimension of the natural size of the ticker tape.
Your Java file will be named TickerTapeTest.java, and should instantiate and display simultaneously several TickerTape objects.
Place your finished .java, .classes and .html files in your public_html so I may grade them.
Space Wars: Make an applet similar to the Asteroids game.
The applet will have the following components:
1. A canvas in which appears a flying spacecraft. The canvas is mapped "mod 1", so that if the spacescraft flies of an edge, it reenters at the opposite edge.
2. A panel which controls the booster rockets. Mouse down on the panel fires the boosters and accelerates the spacecraft in the direction it is pointing. Also, it makes a small red flame shoot out the back!
3. A scroll bar which points the nose of the spacecraft.
The spacecraft flies by inertia, with the rockets adding or subtracting inertia in the direction of the current heading when the boosters are fired. Using a thread, check if the boosters are on, if so, increment the velocity of the spacecraft by a small amount. The current heading should be expressed as (sin theta, cos theta), then the new velocity will be:
```
       new velocity in x = (old velocity in x) + K1 * (cos theta)
       new velocity in y = (old velocity in y) + K1 * (sin theta)
```
and update the spacecraft's position:
```
       new x position = (old x position) + K2 * (velocity in x)
       new y position = (old y position) + K2 * (velocity in y)
```
where K1 and K2 are fudge factors to make the game dynamics feel correct.
Remember to map back the spacecraft on the canvas. Do do this you might want to consider the canvas coordinates to be from 0.0 to 1.0. The mapping will be taking the fractional part.
You will also need some math to draw the spacecraft in its various orientations. Consider a model of the spacecraft centered on (0,0). Rotate it by rotating each of it's defining vertices around (0,0) by the angle theta. Do this by considering the point (x,y) as a vector and applying the matrix:
```
        | cos(theta)  -sin(theta) |
        | sin(theta)   cos(theta) |
```
Then translate the model to be centered on its current screen location (xl, yl). The equation is easy to derive:
```
        xl + ( x * cos(theta) - y * sin(theta) )
        yl + ( x * sin(theta) + y * cos(theta) )
```
Here is a hint for getting started. See the package contents as well.
Place your finished .java, .classes and .html files in your public_html so I may grade them.