Depth perception

The basic problem with displaying three-dimensional data is the dimension we do not have on the screen, namely depth. Firstly, the viewer has to be able to get an idea how far a displayed object is, or at least, which of two objects is further. In order to achieve that, perspective projection, depth cueing, colour coding of depth and, most efficiently, lighting can be used. Secondly, objects that would take up the same area of the screen should all be visible at the same time. To solve this, objects should be made transparent, either by colour blending, or by avoiding solid opaque objects.