added new sanity checks and compile-time assertions to prevent errors

fixed stair-building issue
new test-cases
added elevator support
fixed/improved some walker modules

grid/walk/v2/modules/WalkModulePreventVisited.h

@@ -0,0 +1,77 @@
+#ifndef WALKMODULEPREVENTVISITED_H
+#define WALKMODULEPREVENTVISITED_H
+
+#include "WalkModule.h"
+#include "WalkStateHeading.h"
+
+#include "../../../../data/RingBuffer.h"
+#include "../../../../Assertions.h"
+
+struct WalkStatePreventVisited {
+
+	struct PV {
+
+		RingBuffer<int> history;
+
+		PV(const int size) : history(size) {;}
+
+	} preventVisited;
+
+	/** ctor */
+	explicit WalkStatePreventVisited(const int historySize) : preventVisited(historySize) {;}
+
+};
+
+/**
+ * prevent a state from visiting nodes he has already visited
+ * within a certain timeframe (ringbuffer)
+ *
+ * this should avoid deadlocks in some situations where the transition
+ * just switched back and forth between two nodes
+ *
+ */
+template <typename Node, typename WalkState> class WalkModulePreventVisited : public WalkModule<Node, WalkState> {
+
+private:
+
+public:
+
+	/** ctor */
+	WalkModulePreventVisited() {
+
+		// ensure the templated WalkState inherits from 'WalkStatePreventVisited'
+		StaticAssert::AinheritsB<WalkState, WalkStatePreventVisited>();
+
+	}
+
+
+	virtual void updateBefore(WalkState& state) override {
+		(void) state;
+	}
+
+	virtual void updateAfter(WalkState& state, const Node& startNode, const Node& endNode) override {
+		(void) state;
+		(void) startNode;
+		(void) endNode;
+	}
+
+	virtual void step(WalkState& state, const Node& curNode, const Node& nextNode) override {
+
+		(void) curNode;
+
+		state.preventVisited.history.add(nextNode.getIdx());
+
+	}
+
+	double getProbability(const WalkState& state, const Node& startNode, const Node& curNode, const Node& potentialNode) const override {
+
+		(void) startNode;
+		(void) curNode;
+
+		return (state.preventVisited.history.contains(potentialNode.getIdx())) ? 0.001 : 0.999;
+
+	}
+
+
+};
+#endif // WALKMODULEPREVENTVISITED_H