The purpose of the final is to allow you to explore some aspect of real-time computer graphics that was not covered in class.
The final takes the form of a project similar to those that we've done this semester with one important difference: you may choose the topic. Pick something of interest to you, perhaps something related to your other courses, your career goals, or your ongoing research, if any. Of course, your idea must be approved by the instructor, so contact him in person or by email as early as possible.
Note that this final project is worth more than twice the value of the prior projects (28 points instead of 12 points). You also have nearly twice as much time to complete it (3.5 weeks instead of 2 weeks). Expectations will be higher, so make the project significant.
In addition to the implementation, you must provide documentation. The web page in which you embed your work should describe what you did and how you did it. This should be the equivalent of at least two pages of text. It should link to any sources you've referenced for your implementation, and may include supporting images. Convince the instructor that you understand what you've done.