As part of their senior comps project, four Carleton computer science majors are building a 3D interactive model of campus. The four seniors have been working together with a faculty advisor, Jack Goldfeather, over the course of winter term to bring the project from the drawing board to completion. Paul Wilmes and Henry Gross allowed me to observe them one afternoon while they were doing a final debugging check of the project. The other two students on the team are Ed Williams and Deborah Chasman.
Today Wilmes, Gross, and Goldfeather crowded around a computer terminal, poking through lines of Java code. From what I could gather from their conversation, something was wrong with a slider bar.
The students started their project with an image file, a map of campus downloaded off the Carleton website. It became the floor of their virtual terrain, and the footprints of the buildings helped them to orient their own three-dimensional buildings onto the map.
The computerized versions of the library, the observatory, and other familiar buildings around campus are built up of many simple polygons such as rectangles, triangles, and spheres. A program called Open GL helps the computer how to display these polygons on a two-dimensional screen when they are rotated in a three-dimensional space.
The hardest part of this task has been "tracking down the issues" in the code, says Gross. "We have to go through other people's code" that might or might not be well proofread. If there is an error in any of their 8050 lines of Java code, it could throw the whole thing off. Wilmes agrees that the hardest part has been "tracking down where it's happening."
Goldfeather added that it was difficult "getting everybody's mind wrapped around what has to be done." There is a point at the beginning of computer science comps projects where students do not know where to start.
It has not been an easy task. Computer game designers who build 3D maps like these ones "generally have commercial tools that are already made," says Gross. Carleton seniors, on the other hand, have to develop all those tools from scratch. The point of the project is for them to learn how these tools are put together.
When they had finished looking for bugs in their code, they let me look at the project so far. It looked a lot like the graphics in a video game. Sayles Hill and the chapel were unmistakable as we sailed past them overhead. The viewer can zoom, rotate, and move any direction in space.
By this point in the term, the project is almost finished. Most of the buildings are in place on the model, and they have plans to put in trees. Their task now is to put in the finishing touches and prepare to present their work before the department at the end of the term.
Next year, the completed 3D map will be available for download on the Computer Science department's web page. It does not take much special software to run, only Open GL and a java reader. Information on getting the right software and running the program will be available on the site.
Ultimately, Goldfeather's goal is to put the map up on the admissions webpage so prospective students could zoom around to their heart's content. Other campuses have online tours of campus, but as far as Goldfeather knows, none of them are quite as interactive as this.
