Make your own free website on Tripod.com

JLogo: Implementing Logo using Java.


 !   

The Development of JLogo.


For many people Logo is the first programming language learnt. Here we will see how to implement a subset of Logo using Java. For those of you who have never come across Logo, it is a language which allows you to draw line drawings by giving commands. Here is what your finished product will look like.

Attacking the problem.
In logo we will need to take input from the user. This input will be in form of Logo commands, like fd 10 or forward 10. Then we need to convert these commands into a format which our program can understand. Also we will need to have a GUI element implementing our custom drawing for Logo. We also need to have a file tying all the logic together and showing the GUI.
Lets see the classes we are going to use.
SwingWorker.java and UtilityWorker.java: These classes convert the users input to a format which our Program can understand and draw.
DrawArea.java: This class implements our custom drawing, and draws itself according to the instructions given.
Logo.java: This ties together all the logic.
We also have three more classes, CoOrd.java and OrderedCoOrds.java. These are simple classes which we will use to implement the idea of points and lines. We have a class Turtle to model the turtle which moves on and draws. It has two ints telling the point the turtle is at, an int telling the current orientation and a short which holds the status of the pen.

to next chapter >>>