Constructing a Hermite spline
A Hermit spline consists of four control points, split into two groups:
- A starting and ending vertex
- An incoming and an outgoing tangent
The right side of Figure 7.13 shows a Hermite spline. The two tangents start at the vertices: the incoming tangent begins at the start vertex, and the outgoing tangent starts at the end vertex.
Note
The incoming tangent of a Hermite spline points toward the direction of the spline path, and the outgoing tangent points away from the spline path.
The unequal directions of the two tangents may look a bit strange at first glimpse, as the Bezier spline on the left side of Figure 7.13 is completely inside the polygon created by the four control points. But this definition has a significant impact on the continuity of Hermite splines.
Spline continuity
If we want to join two splines, we must take care of the continuity of the spline path. Just setting the location of the starting vertex of the...
