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Computer Graphics

Figure 5.4 illustrates the various glyphs representing the character ‘a.’

Figure 5.4: Various Glyphs Representing the Character
‘a’

Let us now discuss the different types of glyphs. There are four major types of glyphs. They are:
1. One-Dimensional Glyphs: Different types of dataset of one-dimension can be easily mapped to
any glyph of one attribute. There are many better ways to represent a one-dimensional data than
glyphs. The reason is that the humans do not have any problems looking at one-dimension of
scalar data as the substitution is in the speed of perception.

2. Two-Dimensional Glyphs: Two-dimensional glyphs lend itself to slightly more variation
compared to one-dimensional glyphs. : Two-dimensional glyphs can:
(a) Map both dimensions onto position in 2-D.
(b) Map one-dimension to 1-D position and the other to glyph by changing attribute
(c) Map both dimensions onto non-positional glyph attributes.

3. The Star Glyph: A star glyphs is a glyph with a certain number of points displayed within an
imaginary circle.
4. Polygonal Glyphs: Polygonal glyphs can have different kind of geometries. In other words, the
glyph itself is a polygon or a polygonal object in 2-D and 3-D.

Some characteristics of a glyph such as size, color, orientation, are always data
driven.

Research and find out information on Mayan glyphs translations.

5.4 Aliasing and Anti-aliasing

Aliasing refers to an effect that causes different signals to become indistinguishable at the time of
sampling signals. In other words, when a quickly changeable signal is sampled infrequently then the
signal represents the lower frequency. The lower frequency then replaces the frequency of the original
signal. This is called as aliasing.

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