added several grid-walks

added new helper methods/classes (e.g. for heading)
new test cases
optimize the dijkstra
cleanups/refactoring
added timed-benchmarks to the log
many more...

grid/Grid.h

@@ -15,7 +15,12 @@
 
 /**
  * grid of the given grid-size, storing some value which
- * extends GridPoint
+ * extends GridPoint and GridNode
+ *
+ * Usage:
+ *		for (Node& n : grid) {...}
+ *		for (Node& n2 : grid.neighbors(n)) {...}
+ *
  */
 template <int gridSize_cm, typename T> class Grid {
 
@@ -47,6 +52,12 @@ public:
 	/** no-assign */
 	void operator = (const Grid& o) = delete;
 
+	/** allows for-each iteration over all included nodes */
+	decltype(nodes.begin()) begin() {return nodes.begin();}
+
+	/** allows for-each iteration over all included nodes */
+	decltype(nodes.end()) end() {return nodes.end();}
+
 
 	/**
 	 * add the given element to the grid.
@@ -235,14 +246,14 @@ public:
 		Log::add(name, "running grid cleanup");
 
 		// check every single node
-		for (int i = (int)nodes.size() - 1; i >= 0; --i) {
+		for (size_t i = 0; i < nodes.size(); ++i) {
 
 			// is this node marked as "deleted"? (idx == -1)
 			if (nodes[i]._idx == -1) {
 
 				// remove this node
 				deleteNode(i);
-				++i;
+				--i;
 
 			}
 		}
@@ -261,6 +272,8 @@ private:
 	/** hard-delete the given node */
 	void deleteNode(const int idx) {
 
+		_assertBetween(idx, 0, nodes.size()-1, "index out of bounds");
+
 		// COMPLEX AND SLOW AS HELL.. BUT UGLY TO REWIRTE TO BE CORRECT
 
 		// remove him from the node list (reclaim its memory and its index)