Due: Wednesday March 12th for Berque's section, Thursday March 13th for
Howard's section, and Friday March 14th for Townsend's section. Your
instructor will specify the time at which the project is due. Copy the
folder named graphicstemplate from the public folder to
your own account. Rename this folder as ``Project1''. Do your
work for this project in that folder.
You are required to come to lab on March 4th with two items that will
collectively count as your prelab grade: (a) a paper and pencil
first-attempt at stage one of this project (see below), and (b) a paper
and pencil first-attempt at a solution to a practice problem for exam
one that may be found in I:\public\ExamOne in
exam1LabPrep.doc. During lab you will work to implement this
practice problem on the computer. When you are finished, a tutor or
instructor will check off your work for laboratory credit. Then, you may
use the remaining lab time to work on this project.
Please be sure that your comments contain your name, instructor, and directory number (CSC121XX). You should also include a comment explaining what the program does, as well as any other appropriate comments in the program.
Overview: In planning for next year's holiday buying rush, the software company that has just hired you, Wally's Quick and Cheap Computer Kits, or Wally's QACCK, is developing a new video game. Your job, should you choose to accept it, is to develop an initial version of the game by writing a program that allows the player to try to launch new fuel supplies up to a satellite, which is flying above the earth.
At the start of the game, the player will be asked to select a level of difficulty that will control the speed at which the satellite moves. There are several ways you can let the user select the level of difficulty. Any reasonable method is fine.
Once the difficulty level has been selected, an object (the satellite)
will appear near the upper left corner of the screen. The object should
be any shape, which has not already been defined in
mygraph.h--for example, a rectangle, stick-figure or rocket. The
object will move horizontally across the screen. When the object reaches
the right edge of the screen, its direction should be reversed, and it
should travel back toward the left edge of the screen. When it reaches
the left edge, its direction should be reversed again (this process
should continue until the game is over.) If you prefer to deal with the
edges of the screen in some other manner, that is also fine. For
example, you might decide that when the object hits the right edge of
the screen it should reappear at the left edge again.
Near the bottom center of the screen, display a small ball (there is a
ball class which is already defined in mygraph.h), which is
assumed to contain a fresh fuel supply for the satellite.
If the user presses `S' or `s', the ball (which contains a fresh fuel supply for the satellite) should be launched upward and at an angle that takes it roughly toward the top left corner of the screen; if the user presses `D' or `d', the ball should be launched straight up; and, if the user presses `F' or `f', the ball should be launched at an angle that takes it toward the top right corner of the screen. Once launched, the fuel ball should travel toward the top of the screen in an attempt to intercept the satellite.
If the fuel ball travels off the top of the screen without intercepting the satellite, it should be repositioned back at the bottom of the screen so that the user can press a key to launch it again. The player should be given five chances to intercept the satellite. If the satellite is intercepted, then the game ends and a congratulatory message is printed that thanks the user for saving the satellite. If the fixed number of tries is exceeded and the satellite has still not been intercepted by the fuel ball, then the satellite should fall to the bottom of the screen.
The screen might look something like this (Note that the arrows will not be displayed on the screen; the arrows are just there to indicate the motion of the objects):
Since other programmers working for our small, but growing, software company will expand your program at a later date, it is essential that you design the program well. This includes using functions and parameters to break the program into manageable pieces, selecting good identifier names, indenting the program neatly, and using pre- and post- conditions and other comments to explain the program.
Several aspects of this project have been intentionally left undefined. Feel free to resolve any unspecified design decisions however you see fit. As long as you meet the requirements described above, feel free to be creative and have fun.
This is not a short assignment, and there are some general problem solving strategies that can help you organize your work. You should begin by outlining the main tasks you want the program to perform. Sketch the general outline of the main program and some of the major functions you will use.
It is then essential that you develop your program in stages rather than trying to code a program that does everything at once. This allows you to concentrate on one issue at a time and permits you to thoroughly test each part of your program before you move on. This method of developing software is called incremental coding.
One possible set of stages follows:
mygraph.h, although you are free to define other
shapes if you prefer. When the user presses an appropriate key, the fuel
ball should travel up toward the top of the screen either straight up,
or toward the right or left corner depending on the key that was
pressed. If the user presses a key other than the ones which were
mentioned on the previous page, the program should beep. You will need
to modify the loop, so that the program stops, when the fuel-ball moves
off the top of the screen. Allow the user to launch only ONE fuel ball
at this stage.
Stages 1, 2 and 3 (as described above) compose the basic assignment. Print your program, when you are satisfied that these three stages work correctly and your coding style matches that required by your instructor. Turn in this copy to your instructor. We hope that you will consider the four additional stages below and other modifications of your own choosing. These are not required for full credit. We list them, because we know that students enjoy the unit one graphics environment and are motivated to expand their programs. Graphics programs such as this one extend themselves well to the educational and entertainment fields, as examples. Your instructor will give you more information about how s/he will use your extra work, should you choose to extend your program.
mygraph.h file which is in
your MyLibr directory by defining another type of object, such as
a rectangle. Modify your program to use this new object instead of the
square as the satellite. You can make your new object as simple or as
complex as you like, but if you make it complicated, you may have to
define what it means to intercept the satellite somewhat roughly.