main/src/georegression/geometry/UtilPolygons2D_I32.java
public static boolean isPositiveZ(Point2D_I32 a, Point2D_I32 b, Point2D_I32 c  ) {
		int dx0 = a.x-b.x;
		int dy0 = a.y-b.y;

		int dx1 = c.x-b.x;
		int dy1 = c.y-b.y;

		int z = dx0 * dy1 - dy0 * dx1;

		return z > 0 ;
	}
public static boolean isPositiveZ(Point2D_I32 a, Point2D_I32 b, Point2D_I32 c  ) {
		int dx0 = a.x-b.x;
		int dy0 = a.y-b.y;

		int dx1 = c.x-b.x;
		int dy1 = c.y-b.y;

		int z = dx0 * dy1 - dy0 * dx1;

		return z > 0 ;
	}
Returns true if the cross product would result in a strictly positive z (e.g. z &gt; 0 ). If true then
the order is clockwise.

v0 = a-b
v1 = c-b

@param a first point in sequence
@param b second point in sequence
@param c third point in sequence
@return true if positive z