After some testing Region seems OK

editor/region.cpp

@@ -59,9 +59,6 @@ bool Region::NewTileR(Tile const& tile) {
 }
 
 Tile Region::GetTileR(int tx, int ty, int tw, int th, int minDepth) {
-	//find the first tile at this location, with the specified minimum depth
-	//since neither the Region or Tile classes store the tile sizes,
-	//this function takes the sizes as arguments
 	std::set<Tile>::iterator ptr = tiles.begin();
 	while(ptr != tiles.end()) {
 		//skip the tiles that are too deep
@@ -80,13 +77,17 @@ Tile Region::GetTileR(int tx, int ty, int tw, int th, int minDepth) {
 	if (ptr != tiles.end()) {
 		return *ptr;
 	}
-	return {0,0,0,-1}; //value = -1 is a crappy error code
+	return {0,0,0,-1}; //TODO: value = -1 is a crappy error code
 }
 
 bool Region::DeleteTileR(Tile const& tile) {
 	if (!InBoundsR(tile.x, tile.y)) {
 		throw(std::runtime_error("Deleted tile location out of bounds"));
 	}
+	//sentinel
+	if (tile.value == -1) {
+		return 0;
+	}
 	return tiles.erase(tile);
 }
 

editor/region.hpp

@@ -89,7 +89,7 @@ public:
 	friend bool operator>(Region const& lhs, Region const& rhs);
 	friend bool operator==(Region const& lhs, Region const& rhs);
 
-private:
+public: //TMP
 	int const x;
 	int const y;
 	int const width;

editor/tile.hpp

@@ -29,10 +29,10 @@ struct Tile {
 
 	Tile() = default;
 	Tile(int i, int j, int k, int l) : x(i), y(j), depth(k), value(l) {}
-
-	friend bool operator<(Tile const& lhs, Tile const& rhs);
-	friend bool operator>(Tile const& lhs, Tile const& rhs);
-	friend bool operator==(Tile const& lhs, Tile const& rhs);
 };
 
+bool operator<(Tile const& lhs, Tile const& rhs);
+bool operator>(Tile const& lhs, Tile const& rhs);
+bool operator==(Tile const& lhs, Tile const& rhs);
+
 #endif