Game Development Reference
7.4.12 Fish Eye
The fish eye effect produces an image as seen in a spherical mirror or through
a wide-angle lens. The image produced is hemispherical in nature. Depending
on the amount of curvature in the image, it can look completely distorted
and inside out as the one from Unity in Figure 7.30 . When used in a less
exaggerated manner, the effect widens the field of view, showing more of
the scene than is in the camera's normal range. However, to fit in the extra
parts of the image, at the outer edges the scene starts to bend with the effect,
becoming more exaggerated the farther it is from the center.
7.4.13 Sun Shafts
Sun shafts are produced by a bright light source being partially occluded
and viewed when passing through atmospheric particles. For example, sun
shafts are prominent after a sun shower when the sun is partially blocked
by clouds and the air is heavy with moisture. You might also imagine sun
shafts coming through a dusty attic window or in between the trees
in a rainforest.
This effect as produced in Unity is shown in Figure 7.30 .
Vignetting is an effect used to focus the viewer's attention on an object in
an image by darkening and/or blurring the peripheries. The start of each
James Bond movie provides an example where the viewer is looking down
the barrel of a gun. The view is restricted to a small circle in the middle of
the screen and the supposed inside of the gun barrel sets the outside to
black. Vignetting need not be this dramatic. Instead of the edge darkening
abruptly, it might fade to black instead.
In a game view, a vignette can focus the player's attention on an area of the
game environment or be used to restrict the player's view. Unity's vignette
script is illustrated in Figure 7.30 .
7.4.15 Screen Space Ambient Occlusion (SSAO)
The SSAO effect approximates shadowing in from ambient light based
purely on the image produced by the camera. As it is a postproduction
effect, it does not rely on a light source or on information about an
object's materials to calculate shadows. It works with the image to
emphasize holes, creases, and areas where objects meet. For example,
without any lighting in a game environment to provide dynamic or baked
shadows, trees stand on the terrain but somehow look disconnected
and not in contact. SSAO provides a dusting of shadow around these
connection points such that these types of intersections don't appear