Game Development Reference
In-Depth Information
A generalization emerges from the work of these intercepts. If the intercept value
is 0, then the line crosses the origin. If it is greater than zero, then the line crosses
the
y
axis above the origin. If it is less than 0, then the line crosses the
y
axis
below the origin. Whatever the y-intercept value, as long as the slopes remain the
same, the lines remain parallel.
You can create parallel lines if you set the slope of the line to 1. In this instance,
the equation assumes the form
y ¼ x þ b
, for the slope,
m
, equals 1. To use
Visual Formula to generate a set of lines' slopes set to 1 but y-intercept defini-
tions set at distinct values, follow these steps (refer to Figure 10.27):
1. Click the menu item for Value. Then click in the upper equation compo-
sition area to position the Value field. Type x in the Value field.
2. Click the Add menu item. Then click to the right of the Value field to
position the plus sign.
Figure 10.27
Use y-intercept settings to generate parallel lines.
