Familiarizing yourself with the CMU Graphics Library.^*

• Copy the Graphics Demo folder from "\\Dragon\cls_abrady\CS 420\" to the Temp folder of your PC. Open the project (the graphics-prj file within that folder) and run the demonstration program in the project to get a sense of some of the capabilities of the graphics package.

• Replace the ABdemo.cpp file in the project with the ABhouse.cpp file (which is a subset of the demo program consisting of just the first screen). To do this, highlight ABdemo.cpp in the project window and then choose Remove Selected Items from the Project menu. Then drag-and-drop the ABhouse.cpp file from the Graphics Demo folder to the spot in the project window where you just removed the ABdemo.cpp file. Run the program (CodeWarrior will automatically do any necessary compilation and linking) and make sure that it works.

• Double-click on ABhouse.cpp in the project window to open it for editing. Notice that the graphics package is accessed through a window object that "knows" how to draw. The main function instantiates a window object and "passes messages" to the object telling it to do what is needed to make the drawing.

• Compared to the size of the house and the size of the windows, the door of the house is quite small. Modify the two constants that determine the door size to make it better-proportioned for the size of the house. Run the program to test your changes (again, CodeWarrior will automatically do any necessary compilation and linking).

Save the project to your floppy.

• Remove the object code from the project (there is an option under the Project Menu to do this). You may also need to remove the executable file(s) from the Graphics Demo folder (named Graphics App ..., unless you changed the name of the Target File) to fit everything on your floppy disk. Copy the Graphics Demo folder from the Temp folder to your floppy disk. You should then remove the folder from the Temp folder on the C: drive.

^*The CMU Graphics Library was created by the Carnegie Mellon University School of Computer Science and is used in their introductory programming courses. It is available from Mark Stehlik's Advanced Placement page.