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class Utils

package hxd.poly2tri

@:directlyUsed

Static methods

staticinScanArea(pa:Point, pb:Point, pc:Point, pd:Point):Bool

staticinsideIncircle(pa:Point, pb:Point, pc:Point, pd:Point):Bool

Requirement:
1. a, b and c form a triangle.
2. a and d is know to be on opposite side of bc
               a
               +
              / \
             /   \
           b/     \c
           +-------+
          /    d    \
         /           \
Fact: d has to be in area B to have a chance to be inside the circle formed by a,b and c
d is outside B if orient2d(a,b,d) or orient2d(c,a,d) is CW
This preknowledge gives us a way to optimize the incircle test

Parameters:

pa
  • triangle point, opposite d
pb
  • triangle point
pc
  • triangle point
pd
  • point opposite a

Returns:

true if d is inside circle, false if on circle edge