Introduction to BuggleWorld

Total checkmarks:

Download the folder lab2_programs from the cs111d download directory on cs.wellesley.edu. Directions for using Fetch in CS111 are available here.

If you are using a PC at home, an analog of Fetch on a PC is called WinSock FTP. Here is a WinSock FTP tutorial.

Saying "Hi" to BuggleWorld

Run the project in this folder. Follow the directions in overview of Code Warrior with applets. What you will see is BuggleWorld, a special microworld we have created for CS111 students to have fun exploring programming ideas! Try clicking on a couple of buttons to see how BuggleWorld works.

Here's a quick summary of the most important buttons:

Run -- runs a program in BuggleWorld

Reset -- puts BuggleWorld back to its initial state
Reset must be hit before you can Run a program again.

Step -- Each press of Step executes (roughly) one line of the program. Step can not be used if the program has been Run unless BuggleWorld is Reset.

Also note that you can just play with the BuggleWorld options without running the program involved. You just need to create a new Buggle() before any BuggleWorld methods can be invoked.

Task 1: Write down the sequence of buttons which must be pressed to get "Hi" as shown below (the result of hitting the "Run" button).
Task 2: Study the file Hi.java in the project which is the code we've been observing. Check if it performs the same sequence of steps that you have come up with. Run the project. You should see a picture that looks like this:

Exercise 1. Jumping into CS

Now you're all ready to write your first BuggleWorld program! The goal is to write "CS" as shown below.

For the first assignment we will just change the code that we have been given.

Task 3: Comment out the code that prints Hi, i.e. put comment symbols /* and */ around it. Do not comment out the header of the method run(). The file Hi.java should look like this:
```
import java.awt.*;


/* 
   CS111 Lab 1 -- Task 1 -- Spring 2000
   ben, and barb collaborate to say "Hi".
   ben draws a "H", barb draws a "i",
*/


public class Hi extends BuggleWorld {
		
  public void run () {

/* 
 	// ben draws a "H"
	Buggle ben = new Buggle(); 
	... the rest of the code ... 
	barb.dropBagel(); // barb dots her "I"
	barb.backward(4);
*/

    
  }
  
}
```
Note that the closing squiggly brackets are outside of the comment, they must be black, not red.
Change setDimensions(9,9) to setDimensions(13,13) in the init() method in the beginning of the file, since letters "CS" take more room than "Hi" (see the picture).
Compile and run the program. The grid should be 13 by 13. Pressing Run on the BuggleWorld applet should cause no action (i.e. nothing is written and no buggles are created).
Task 4: Using the code that you have commented out as a sample, write code that writes CS.
The best way to write a program is to write a few lines of code, then test it by running the program, then add another few lines, test, and so on.
Try to make the picture exactly the same as shown above.

Exercise 2. More writing...

If you have time left, change your program to draw other letters or figures.

In the end of the class

Save your work either on a ZIP disk (better), or by uploading to your drop folder using Fetch. You can later use it as a reference. Make sure that you don't store your files on cs111 server for too long -- when you get a chance, download them to your home computer or save them to a ZIP disk and remove from the server.

After you have saved your work, please make sure to delete your folder on the computer that you were using and empty the trash!

Run	--	runs a program in BuggleWorld
Reset	--	puts BuggleWorld back to its initial state Reset must be hit before you can Run a program again.
Step	--	Each press of Step executes (roughly) one line of the program. Step can not be used if the program has been Run unless BuggleWorld is Reset.