dijkstra is now bleching fast

deleting from the grid is now bleaching fast
added new helper methods
many new test-cases
many new methods for geo classes and others
added a bunch of new grid-walkers

geo/Point3.h

@@ -2,6 +2,7 @@
 #define POINT3_H
 
 #include <KLib/Assertions.h>
+#include <cmath>
 
 /**
  * 3D Point
@@ -28,6 +29,12 @@ struct Point3 {
 
 	Point3& operator /= (const float v) {x/=v; y/=v; z/=v; return *this;}
 
+	Point3& operator += (const Point3& o) {x+=o.x; y+=o.y; z+=o.z; return *this;}
+
+	Point3& operator -= (const Point3& o) {x-=o.x; y-=o.y; z-=o.z; return *this;}
+
+	bool operator == (const Point3& o) const {return x==o.x && y==o.y && z==o.z;}
+
 	/** read-only array access */
 	float operator [] (const int idx) const {
 		_assertBetween(idx, 0, 2, "index out of bounds");
@@ -36,6 +43,14 @@ struct Point3 {
 						return z;
 	}
 
+	/** get the distance between this point and the other one */
+	float getDistance(const Point3& o) const {
+		const float dx = x - o.x;
+		const float dy = y - o.y;
+		const float dz = z - o.z;
+		return std::sqrt(dx*dx + dy*dy + dz*dz);
+	}
+
 	float length() const {return std::sqrt(x*x + y*y + z*z);}
 
 	float length(const float norm) const {