Added type alias for std::pair<uint8_t,uint8_t> for grid coordinates as sf::Vector2 cannot be used in std::map or std::set

src/Utils.h

@@ -12,6 +12,8 @@
 
 namespace pro_maat
 {
+// Used with positions on the map grid
+using GridPos = std::pair<uint8_t,uint8_t>;
 
 static constexpr uint8_t pixelsPerUnit = 50;
 static constexpr char levelFolder[] = "resources/";
@@ -20,6 +22,14 @@ static constexpr char fontFolder[] = "resources/";
 
 void errorWindow(const std::string& error);
 
+// Good heuristic on 4-way grids
+double manhattanDistance(pro_maat::GridPos leftHandSide, pro_maat::GridPos rightHandSide)
+{
+    // The *0.01 helps with breaking ties and minimizing exploration
+    // As per http://theory.stanford.edu/~amitp/GameProgramming/Heuristics.html#breaking-ties
+    return (std::abs(rightHandSide.first-leftHandSide.first)+std::abs(rightHandSide.second-leftHandSide.second))*1.01;
+}
+
 }
 
 #endif //PROJECT_MAAT_UTILS_H