CSCI 1321 (Principles of Algorithm Design II), Spring 2010:
Homework 8

Credit

Design 20 points; code 40 points.

Overview

The goal of this homework is to make your game as polished as possible in the time remaining -- both from the standpoint of a person playing it and from the standpoint of a person reading your code. If you think what you turned in for Homework 6 is as perfect as you can make it, just resubmit it for this assignment; if I agree, you'll get full credit.

Design and Code

There are several categories of improvements you should consider making:

• Fix any known bugs in your code, including adding classes you didn't write in previous assignments (for example, you want to have two kinds of enemies but only implemented one in earlier assignments).

• Improve the look of the game in whatever way seems appropriate -- for example, by using the screen editor to draw a more complex map, or by figuring out how to produce nicer images for blocks and entities (using Java's graphics library classes or by importing images from files). This could also be a time to change from moving in whole-block units to moving in partial-block units. I discouraged this early on because the logic is a bit more complex, but it turns out to be less complex than in previous years because of additional functionality in the game framework.

• Tidy up your code. This includes correcting any problems I pointed out in grading your other assignments (yes, I know that I haven't returned comments on all your work yet), as well as the following.
  • Try to avoid duplicating information in a way that makes it difficult to change (i.e., you must change something in multiple places). Examples:
    • If you create an array (in your screen class, for example), by writing

      Block[][] blocks = new Block[20][30];

      then elsewhere in the class you should use blocks.length (not 20) for the number of rows and blocks[0].length (not 30) for the number of columns. Outside the class you should also avoid hardcoding the 20 and 30 (or obvious variants such as 19 and 29) as well. (For the dimensions of a screen s, you can use s.getSize().height and s.getSize().width.)

    • Once you've used Location.setPartialsInWhole() to set the ``partials in whole'' number, you should use Location.getPartialsInWhole() to get the value rather than hardcoding the desired number.

  • Try to avoid duplicating code. If you have the same code repeated multiple places, especially if there's a lot of it, consider making the duplicated code a private method.

  • Be sure all instance variables for a class are declared in one central place (top or bottom) rather than being scattered throughout the class.

  • Be sure visibility of methods and instance variables (public, private, etc.) is sensible. Variables should normally be private; methods should be public if needed outside the class, private if not.

  • Be sure names of classes, variables, and methods are consistent with Java naming conventions: Classes are mixed-case starting with upper case, constants (static final variables) are upper-case, and other variables are mixed-case starting with lower case.

  • Remove or comment out any code that prints debugging information.

• Make the documentation consistent with the current state of the code and reasonably complete. I will grade the HTML version of your documentation, so be sure it includes everything you want me to read. If you haven't already done so, at this point you should do the following.
  • Be sure every class, and every public method or variable, has at least a brief comment describing what it is and how it fits into your game. (Exception: You do not need to describe how your list and priority queue classes fit into the game, just what they are in general -- e.g., ``linked list of game entities''.) For methods, also describe parameters and return values, unless their purpose is clear from their names and the overall comment about the method.

  • Be sure comments are consistent with the final state of the game. Ideally they will all be your comments rather than Dr. Lewis's instructions for how to use his code (this is particularly applicable to your game setup class).

• Undo any changes you made for Homework 7 that would make the game less playable -- i.e., either remove the code to process command-line arguments and print timing information, or revise things so that if no command-line arguments are supplied the program uses sensible defaults and doesn't print timing information. (You won't need to do this if, as recommended, you made no changes in Homework 7 other than those required to implement and test the additional priority-queue implementation; you can just start from Homework 6.)

Step-by-step instructions

• As with previous assignments, create a new Eclipse project for this assignment and copy into it the package from the previous assignment (here, either Homework 6 or Homework 7, depending on what changes you made in Homework 7).

• Revise your documentation and code until you're happy with it.

• Generate HTML documentation for your project as described in the Project Description and check that it's okay using a browser.

• Turn in your code by sending me mail with all of the files I need to compile and run your game as attachments. This includes all (.java files), any file(s) created using the screen editor, and any file(s) containing images. All of these files will probably be in the same directory containing your Eclipse project (same name as the project, in your Eclipse workspace directory), unless you put them somewhere else. You don't need to send me .class files or the JAR file, but if it's simplest for you just to send me all the files in the directory for your Eclipse project, do that. It's better to send a bit too much than not enough!

  The ``General requirements'' section of the Project description has more suggestions about how to send me the needed files.

  Please use a subject line such as ``csci 1321 code 8''.

Files and links

• The JAR file for this assignment, PAD2S10Assn8.jar. (This JAR file is essentially the same as the one for Homework 5, included again here for completeness.)

• Project Description.

• Project API (Lewis game framework).

• Java library API.

• Help for Dr. Lewis's screen editor program. Instructions for starting the program can be found under ``Project tools'' near the end of the Project Description.

• Help for Dr. Lewis's image editor program. Instructions for starting the program can be found under ``Project tools'' near the end of the Project Description. This is a nice program for creating images for your blocks and entities, but if you have another favorite tool, you can probably use that. Ask me for details about loading images from files.