3D graphics is usually concerned with projecting a 3D scene onto a 2D screen. The idea is much like taking a photograph: light from a 3D scene is funnelled onto a 2D surface. 3D programming essentially tries to do the same thing, mathematically. Usually thirty times a second for a changing scene! There are many different techniques; some are fast but inaccurate, some are fast but limiting, some are fast but use lots of memory, some are slow but easy to code, some are slow but powerful... you can usually combine different techniques depending on what you need. |
