fixed issue with stairs not connected to both floors (start/end)

added additional sanity check

grid/factory/v2/Stairs2.h

@@ -35,10 +35,14 @@ private:
 
 	/** helper struct */
 	struct StairNode {
+
 		const int x_cm;
 		const int y_cm;
 		const int belongsToQuadIdx;
+
+		float z_cm;			// interpolated
 		int gridIdx = -1;
+
 		StairNode(const int x_cm, const int y_cm, const int quadIdx) : x_cm(x_cm), y_cm(y_cm), belongsToQuadIdx(quadIdx) {;}
 	};
 
@@ -94,8 +98,7 @@ public:
 
 		}
 
-		// add the new nodes to the grid
+		// reconstruct the z-value for each node using interpolation
-		// nodes that are near to the two floors that stair is within, are replaced by already existing floor-nodes!
 		for (StairNode& sn : stairNodes) {
 
 			// use the nodes (x,y) to reconstruct the z-value for this position using barycentric interpolation
@@ -112,19 +115,48 @@ public:
 			int z_cm;
 			float u,v,w;
 			if (helper.bary(p, p1.xy(), p2.xy(), p3.xy(), u, v, w)) {
-				z_cm = p1.z*u + p2.z*v + p3.z*w;
+				sn.z_cm = p1.z*u + p2.z*v + p3.z*w;
 			} else {
 				helper.bary(p, p1.xy(), p3.xy(), p4.xy(), u, v, w);
-				z_cm = p1.z*u + p3.z*v + p4.z*w;
+				sn.z_cm = p1.z*u + p3.z*v + p4.z*w;
 			}
 
+		}
+
+		// this might lead to stairs the start slightly above the starting-floor
+		// or end slightly below the ending floor. this would lead to DISCONNECTION!
+		// therefore re-scale the z-values to ensure they start at floor1 and end at floor 2
+		float minZ = +9999999;
+		float maxZ = -9999999;
+		for (const StairNode& sn : stairNodes) {
+			if (sn.z_cm < minZ) {minZ = sn.z_cm;}
+			if (sn.z_cm > maxZ) {maxZ = sn.z_cm;}
+		}
+		for (StairNode& sn : stairNodes) {
+			const float zPercent = (sn.z_cm - minZ) / (maxZ - minZ);				// current percentage from minZ to maxZ
+			sn.z_cm = floor->getStartingZ()*100 + zPercent * floor->height*100;		// apply percentage to floorStartZ <-> floorEndZ
+		}
+
+		// track z-positions of already-existing grid nodes we connected the stair to
+		// if this list contains 2 distinctive values, the stair is successfully connected to starting and ending floor!
+		std::unordered_set<float> connectedWithHeights;
+
+		// add the new nodes to the grid
+		// nodes that are near to the two floors that stair is within, are replaced by already existing floor-nodes!
+		for (StairNode& sn : stairNodes) {
+
 			// the to-be-added position
-			GridPoint gp(sn.x_cm, sn.y_cm, z_cm);
+			GridPoint gp(sn.x_cm, sn.y_cm, sn.z_cm);
 
 			// if a node is near an existing one (the floor above/below) use the existing one!
 			// this ensures the stair is connected to the floor above and below
 			if (grid.hasNodeFor(gp)) {
+
 				sn.gridIdx = grid.getNodeFor(gp).getIdx();
+
+				// remember the z-position of the already-existing grid-node we connected the stair to
+				connectedWithHeights.insert(grid[sn.gridIdx].z_cm);
+
 			} else  {
 
 				sn.gridIdx = grid.add(T(gp.x_cm, gp.y_cm, gp.z_cm));
@@ -141,14 +173,16 @@ public:
 					if (n) {toDelete.push_back(n);}
 				}
 
+				// mark the node as stair-node
+				grid[sn.gridIdx].setType(GridNode::TYPE_STAIR);
 
 			}
 
-
-
-
 		}
 
+		// sanity check
+		Assert::isTrue(connectedWithHeights.size() == 2, "stair is not correctly connected to starting and ending floor!");
+
 		// now connect all new nodes with their neighbors
 		// do not perform normal grid-connection but examine the nodes within the generated vector
 		// this allows for some additional checks/criteria to be used