|
Sampling in the Postfiltering method.
In both figures, the display resolution is four pixels wide by three
pixels high. The superimposed grid depicts the size of a pixel. Both
figures show supersampling at three times the height and three times
the width of the display resolution.
In the right figure, the samples are regularly spaced. In the left figure,
the positions of samples are displaced by a random amount. The
random amount is small relative to the size of the pixel. This method
of perturbing the sample positions is known as "jittering." Jittering
adds noise to the rendered image. The advantage of jittering is that
the human eye tolerates noise more easily than it tolerates aliasing
artefacts, and as a result, humans perceive a higher quality in the
rendered image.
|