added support for .obj objects within the floorplan

include objects within navmesh calculation
include objects within 3d mesh generation
minor changes/fixes

geo/ConvexHull2.h

@@ -0,0 +1,64 @@
+#ifndef GEO_CONVEXHULL2_H
+#define GEO_CONVEXHULL2_H
+
+#include "Point2.h"
+
+#include <algorithm>
+#include <vector>
+
+/**
+ * get a convex-hull around a set of 2D points
+ * https://en.wikibooks.org/wiki/Algorithm_Implementation/Geometry/Convex_hull/Monotone_chain
+ */
+class ConvexHull2 {
+
+public:
+
+	//using namespace std;
+
+	typedef double coord_t;		// coordinate type
+	typedef double coord2_t;	// must be big enough to hold 2*max(|coordinate|)^2
+
+	// 2D cross product of OA and OB vectors, i.e. z-component of their 3D cross product.
+	// Returns a positive value, if OAB makes a counter-clockwise turn,
+	// negative for clockwise turn, and zero if the points are collinear.
+	static inline coord2_t cross(const Point2 O, const Point2 A, const Point2 B) {
+		return (A.x - O.x) * (B.y - O.y) - (A.y - O.y) * (B.x - O.x);
+	}
+
+	// Returns a list of points on the convex hull in counter-clockwise order.
+	// Note: the last point in the returned list is the same as the first one.
+	static inline std::vector<Point2> get(std::vector<Point2> P) {
+
+		auto comp = [] (const Point2 p1, const Point2 p2) {
+			return p1.x < p2.x || (p1.x == p2.x && p1.y < p2.y);
+		};
+
+		int n = P.size(), k = 0;
+		if (n == 1) return P;
+		std::vector<Point2> H(2*n);
+
+		// Sort points lexicographically
+		std::sort(P.begin(), P.end(), comp);
+
+		// Build lower hull
+		for (int i = 0; i < n; ++i) {
+			while (k >= 2 && cross(H[k-2], H[k-1], P[i]) <= 0) k--;
+			H[k++] = P[i];
+		}
+
+		// Build upper hull
+		for (int i = n-2, t = k+1; i >= 0; i--) {
+			while (k >= t && cross(H[k-2], H[k-1], P[i]) <= 0) k--;
+			H[k++] = P[i];
+		}
+
+		H.resize(k-1);
+		return H;
+
+	}
+
+
+};
+
+#endif // GEO_CONVEXHULL2_H