These early SGI machines did not have good support for printing. Even if you did have a printer, the only way to print was to take a screenshot, which had much lower resolution than laser printers and did not look good.

My first paid job - this was after the 10th grade in high school - was writing a kind of printer driver for one of these machines. One of the researchers at a local university had the same problem you did, and heard about this kid who was supposed to be good with computers :)

The SGI GL manuals (this was before it became OpenGL) included all the mathematical formulas they used to display the graphics - the rotation and perspective matrices to transform the coordinates, the vector cross products to calculate shading, and so on. I took these and implemented a subset of GL which outputted PostScript commands to a text file. This was then sent straight to a laser printer (Apple, I think). I didn't implement everything that SGI did, of course - no smooth shading and I think I could handle only the simplest types of occlusion. But it was good enough to handle the models that the researchers needed to print.

I still remember the SGI manuals in big 3 ring binders. This is what I learned linear algebra from - thanks guys.