classHPatch 01
Detailed Description¶
Defines a valid 4 point patch.
Internal Hash Patch is essentially defined by 4 Hermite splines. So there is 8 tangents around a 4 point patch. One in tangent and one Out tangent for each CP.
CP-Tangents.gif
**Relations between In tangents, Out tangents and CPs**
A Hash patch does not have the 4 central vectors called "Twist vectors" as is the case with Bezier surfaces. Instead of these twist vectors, A:M uses a heuristic to decide how to subdivide the patch based on the curviest splines first.
Starting with a HPatch, one can walk the splines by first retrieving the HCPs and then using the HCP::GetSpline() function.
PDF document describing the Hash patches.
Definition at line 53 of file HPatch.h.