Game Development Reference
Figure 3.8 Do you see 4 roses of same size more or less separated or 4 roses on the same plane?
Figure 3.9 Do you see an ellipse in front of a rectangle or an ellipse at the same distance as the
rectangle cut at one side?
4 Gradient of the texture of a surface:
The texture of a surface is perceived clearly if the surface is placed at a slight distance.
This gradient of the texture gives additional information about depth.
5 Variation of visibility in an outdoor scene:
The visibility of an outdoor scene decreases with the thickness of the atmospheric layer,
and hence the depth (Figure 3.10).
6 Parallax caused by movements:
When an observer moves, the retinal images of stationary objects have relative move-
ments depending on their distances. It is the same when the objects move relatively to
each other. In practice, we can use this rule to show the depth by rotating a product or
an entire 3D scene shown on a monoscopic screen. We can also modify the images on
the screen, monoscopic or stereoscopic, depending on the movement of the observer
in front of the screen. But this solution is more difficult in practice because it requires
detecting the position of the observer's head in real time.