many changes and updates

- changed the wifi-estimation api
- adjusted test-cases
- worked on grid-bulding and grid-importance
- new walking modules
- fixed some minor issues

grid/Grid.h

@@ -221,13 +221,14 @@ public:
 		Assert::isBetween((int32_t)p.y_cm, -max, +max, "y out of bounds");
 		Assert::isBetween((int32_t)p.z_cm, -max, +max, "z out of bounds");
 
-		// shift by half of the allowed width of 20 bit to allow negative regions
+		// shift by half of the allowed width of 20 bit to allow negative regions:
+		// -> 19 bit positive and 19 bit negative
 		const uint64_t center = 1 << 19;
 
 		// build
-		const uint64_t x = std::round((p.x_cm+center) / (float)gridSize_cm);
-		const uint64_t y = std::round((p.y_cm+center) / (float)gridSize_cm);
-		const uint64_t z = std::round((p.z_cm+center) / (float)gridSize_cm * 5);		// z is usually much lower and not always aligned -> allow more room for hashes
+		const uint64_t x = center + (int64_t) std::round((p.x_cm) / (float)gridSize_cm);
+		const uint64_t y = center + (int64_t) std::round((p.y_cm) / (float)gridSize_cm);
+		const uint64_t z = center + (int64_t) std::round((p.z_cm) / (float)gridSize_cm * 5);		// z is usually much lower and not always aligned -> allow more room for hashes
 
 		return (z << 40) | (y << 20) | (x << 0);
 
@@ -256,6 +257,11 @@ public:
 		disconnectUniDir(n2, n1);
 	}
 
+	/** remove the connection from n1 to n2 (not the other way round!) */
+	void disconnectUniDir(const int idx1, const int idx2) {
+		disconnectUniDir(nodes[idx1], nodes[idx2]);
+	}
+
 	/** remove the connection from n1 to n2 (not the other way round!) */
 	void disconnectUniDir(T& n1, T& n2) {
 		for (int n = 0; n < n1._numNeighbors; ++n) {
@@ -291,7 +297,11 @@ public:
 
 		// disconnect from all neighbors
 		while (node._numNeighbors) {
+
+			// by removing one neighbor, all others are shifted to close the gap within the array
+			// its therefor ok to always delete array index [0]
 			disconnectBiDir(node._idx, node._neighbors[0]);
+
 		}
 
 		// remove from hash-list