added new sanity-check assertions

fixed issue with angles [bad interface]
- adjusted other parts accordingly
- added corresponding test-cases
started working on absolute heading

grid/walk/v2/GridWalker.h

@@ -104,9 +104,19 @@ public:
 		//if (cnt != 0) {probability /= cnt;} else {probability = 1.0;}
 		probability = 1.0;
 		//probability  = (maxEdgeProb.isValid()) ? (maxEdgeProb.get()) : (1.0);		// dist_m might be zero -> no edges -> no maximum
-		probability *= curNode->getWalkImportance();// < 0.4f ? (0.1) : (1.0);			// "kill" particles that walk near walls (most probably trapped ones)
+
+		// add the walk importance to the probabiliy [each node has a to-be-walked-probability depending on its distance to walls, etc...]
+		const float walkImportance = curNode->getWalkImportance();
+		Assert::isNotNaN(walkImportance, "grid-node's walk-importance is NaN. Did you forget to calculate the importance values after building the grid?");
+		Assert::isBetween(walkImportance, 0.0f, 2.5f, "grid-node's walk-importance is out of range. Did you forget to calculate the importance values after building the grid?");
+		probability *= walkImportance;// < 0.4f ? (0.1) : (1.0);			// "kill" particles that walk near walls (most probably trapped ones)
+
+
 		//probability = std::pow(probability, 5);
 
+		// sanity check
+		Assert::isNotNaN(probability, "detected NaN grid-walk probability");
+
 		// update after
 		updateAfter(currentState, *startNode, *curNode);