Game Development Reference
In-Depth Information
Figure 7.4
The graph of an absolute value rises to the left and right of the y axis.
When you create a graph in which the points are at equal positions across a given
line, they are symmetric with respect to the line. For example in Figure 7.4, the
y
axis is a line of symmetry for the two values you generate as you work with the
absolute values of
x
. You can also refer to points you generate in this way as
reflections of each other. As reflections, they are
mirrored
across the
y
axis.
Translation and Shift
You can alter functions that incorporate absolute values so that you move your
graph along the
x
or
y
axis. This activity is known as translation. To see how this
is so, consider again the equation used to generate a graph that is symmetrical to
the
y
axis (see Figure 7.4):
f ðxÞ¼j
x
j