Asdraw Library

The architecture of the asdraw package

The asdraw package extends the functionality of the adraw package by providing an interface to the tunes package and allowing the programmer to turn the programs designed for the isdraw library into applets. There is no need to change anything in the original program other than to import asdraw package instead of isdraw package and replace the call to bigBang method by creating a class that extends the WorldApplet class.

WorldApplet class

This class informs the applet about the specifics of your world and its parameters. The programmer must implement the method setSize that specifies the dimensions of the Canvasand implement the method getWorld that produces the initial instance of the programmer's world.

Additionally, the programmer can override the method setTickInterval to change the range of speeds available from the game's speed-control slider by setting the minimum and maximum tick rate range. Note, that the higher rate represents slower speeds. Of course, these are the speed values specified in the bigBang method in the isdraw library.

Here is a sample of our TunesDemoApplet class:

public class TunesDemoApplet extends WorldApplet{
  
  /** 
   * Produce a new TunesWorld
   */
  public World getNewWorld(){    
    return new TunesWorld();
  }
  
  /**
   * Set the size of this world
   */
  public void setWorldSize(){
    this.WIDTH = 600;
    this.HEIGHT = 400;
  }

  /**
   * Set the shortest and the longest interval between ticks 
   * for this game in miliseconds
   */
  public void setTickInterval(){
    this.MIN_TICK = 0.1;
    this.MAX_TICK = 0.4;
  }
}

This is sufficient to launch the applet from the command line or as a Java Applet application.

The following html code can be used to upload the applet on a web page. Detailed instructions for creating applets is given in the web pages for the adraw library.

Sample complete html file:

<html>
  <head>
    <title>
      Web page title: My applet
    </title>
  </head>
  
    <body>
      <h2> My Applet Header</h2>

<p>This is how you play my game. 
      Please, use the slider to set the clock speed 
      before starting the game.</p>

<applet
code="MyWorldApplet.class"
archive="myworld.jar, 
         ./asdraw/asdraw.jar, 
         ./tunes/tunes.jar, 
         ./geometry/geometry.jar, 
         ./colors/colors.jar"
width="400"
height="400">
</applet>

     <hr></hr>

... additional webpage contents ...

   </body>
  </html>

Directory structure

The directory structure for this applet looks as follows:

MyAppletFolder       ... the main applet folder
   MyApplet.html     ... the html file defined above
   myApplet.jar      ... a jar file that contains 
                             MyWorldApplet.java, 
                             MyWorld.java,
                             and all other files my world uses
   asdraw             ... a subdirectory
        asdraw.jar    ... the Applet world library
   tunes             ... a subdirectory
        tunes.jar    ... the Applet world library
   geometry          ... a subdirectory
        geometry.jar ... the geometry library
   colors            ... a subdirectory
        colors.jar  ... the colors library