Homework 7 - Virtual Pest (part 3) by JLPopyack & Paul Zoski Due Date: Monday, December 2 at Midnight Late Due Date: Wednesday, December 4 at Noon

PURPOSE:

This is the final part of a three-part assignment. The requirements for the first part were for you to design a virtual pest and its behavior. The requirements for the second part were for you to implement the user interface and design the structure for the software that implements the behavior. The final part is to add the described behavior using JavaScript functions and statements.

THE ASSIGNMENT:

This assignment consists of three sections:

1. Suggested problems (not to be turned in) from the text.
2. Written problems to be turned in.
3. A design project (Virtual Pests).

1. Suggested Problems (from the Decker & Hirshfield text):
   

   From the Analytical Engine text: Module 5.9, pp. 198-199, problems 9, 12, 19
   Module 9.6, p324, problem 3, 4, 6 (very important), 8
   
   

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2. Problems to be turned in:
   From the Analytical Engine text: Module 5.9, pp. 198-199, problems 10
   
   

   1. (10 points) For each of the following loops, supply the missing piece of code so that 12 *'s will be printed on the web page. (Submit the entire code, not just the missing piece of code).
      
      

      1. for( var index = 1; index <= _________________ ; index ++ )
         
           document.write("*")

      2. for( var index = _________________ ; index <= 30 ; index ++ )
         
           document.write("*")

      3. for( var index = 30; index >= _________________ ; index -= 2 )
         
           document.write("*")

   2. (10 points) Write a JavaScript function StarBar(number) that will print number *'s on a web page. For example StarBar(6) will print
      

      ******

      and StarBar(9) will print
      

      *********

      (including an line break). (You may wish to write a test page for you function before submitting it).

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3. Virtual Pests, part 3:
   

   Using the table of behaviors you specified in Parts I-II as a guide, complete your virtual pest by translating these to the appropriate JavaScript commands and testing them for correctness.

   Also upload your completed pest to your course website and supply the URL (on your gradesheet).

   DETAILS:

   As discussed in class, you need to link your form elements to functions so that the values of the form elements may be transferred to the function for processing, then back to the form for display purposes. See the class lecture notes on Forms and Functions for more details on accomplishing that.

   A sample virtual pest based on the example in Parts I-II has been provided for your assistance in this regard. Several points are worthy of note:

   • The sample pest contains minimal functionality - just enough to illustrate all key points, and not enough to fulfill the requirements for the assignment.
   • The sample pest contains functions Init(), ShowState(), Pat(), and Simulate(), which respectively
     1. initialize the pest
     2. update the display to reflect the pest's state
     3. handle the "Pat dog" button click event, and
     4. continues cycling through states according to the pest design.
   • The script is heavily commented to explain the way the functions work and interact.
   • The pest's HTML form contains a text box named "state" that shows the pest's state at all times. Normally, after testing, this would be hidden. Follow the directions in the comments to hide this text box (DO NOT REMOVE IT, JUST HIDE IT!!!) when testing is complete.
   • The pest's HTML form also contains a text box named "counter" that counts the number of times the Simulate() function has been invoked. This is not needed, but is useful in testing so that it is obvious that updates are still occurring even when no state changes occur (as in when the sample pest is "lonely" and waits for the owner to click the "Pat dog" button.
   • Follow the directions in the comments to hide this text box (DO NOT REMOVE IT, JUST HIDE IT!!!) when testing is complete.
   • The sample pest also shows the original finite state machine and behavior table. This is for illustrative purposes only - your pest should not include these here.
   • Note that this pest does not change pictures as it changes states. You will have to modify the code so picture changing occurs. Hopefully, you are an expert at that by now!

   You should upload your virtual pest to your website and provide its URL on your gradesheet.

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4. Extra Credit

   Students are encouraged to have fun with their pests. You may add any features you desire, such as sound or animation. Be creative. You might get points for it.
   

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WHAT TO TURN IN:

All work is to be submitted electronically via WebCT. It is suggested you complete your work early so that a TA can help you if you have difficulty with this process.

• Submit an electronic copy of your answers to "Written problems to be turned in."
• Print out a grade sheet using our grade sheet generator and submit it to your TA in lab (even if you have not submitted your assignment yet). Your TAs will record your grades and comments for you, and return the sheets to you the following week.
• Submit your working virtual pest web page, along with any additional files (e.g. pictures) that it needs.
• Include a written summary of the behaviors you originally specified, and a description of any differences in your final product from your original design.
• Include a written description of any elements you have included which go beyond the requirements of the assignment, to be considered for bonus points.

ACADEMIC HONESTY:

You must compose all written material yourself, including answers to book questions. All material taken from outside sources must be appropriately cited. If you need assistance with this aspect of the assignment, see a consultant during consulting hours.