Merge pull request #4 from Dragosha/master

I would like to merge this...

README.md

@@ -221,6 +221,60 @@ end
 If your state space is huge, occasionally call astar.reset_cache() to free unused memory.
 
 
+
+## astar.get_at(`x`, `y`)
+
+Returns the value from the map array by coordinates.
+
+**PARAMETERS**
+
+X, Y of the tile possition on array not the screen position.
+
+* ```x``` (int) - Tile X
+* ```y``` (int) - Tile Y
+
+
+**RETURN**
+
+* ```value``` (int)
+
+
+**EXAMPLE**
+
+```lua
+
+local value = astar.get_at(1, 1)
+
+if value > 0 then
+	print("boo")
+end
+
+```
+
+
+## astar.set_at(`x`, `y`, `value`)
+
+Set your value to the map array by coordinates.
+*Setting new data reset the current cache.
+
+**PARAMETERS**
+
+X, Y of the tile possition on array not the screen position.
+
+* ```x``` (int) - Tile X
+* ```y``` (int) - Tile Y
+* ```value``` (int) 
+
+
+**EXAMPLE**
+
+```lua
+
+astar.set_at(1, 1, 0)
+
+
+```
+
 ---
 
 ## Games using A-Star

astar/include/Map.hpp

@@ -73,6 +73,7 @@ class Map : public Graph
     void ResetPath();
     void ClearPath();
     int WorldAt(int x, int y);
+    void SetToWorldAt(int x, int y, int value);
     void NodeToXY( void* node, int* x, int* y );
     void* XYToNode( size_t x, size_t y );
 

astar/src/Map.cpp

@@ -18,6 +18,15 @@ int Map::WorldAt(int x, int y)
     }
 }
 
+void Map::SetToWorldAt(int x, int y, int value)
+{
+    if (x >= 0 && x < worldWidth && y >= 0 && y < worldHeight)
+    {
+        ResetPath();
+        world[y * worldWidth + x] = value;
+    }
+}
+
 void Map::ResetPath()
 {
     if (pather != NULL)

astar/src/astar.cpp

@@ -117,6 +117,24 @@ static int astar_reset(lua_State *L)
     return 0;
 }
 
+static int astar_get_at(lua_State *L)
+{
+    int x = luaL_checkint(L, 1);
+    int y = luaL_checkint(L, 2);
+    int ret = map.WorldAt(x, y);
+
+    lua_pushinteger(L, ret);
+    return 1;
+}
+
+static int astar_set_at(lua_State *L)
+{
+    int x = luaL_checkint(L, 1);
+    int y = luaL_checkint(L, 2);
+    int value = luaL_checkint(L, 3);
+    map.SetToWorldAt(x, y, value);
+    return 0;
+}
 
 static int astar_solve(lua_State *L)
 {
@@ -222,6 +240,8 @@ static const luaL_reg Module_methods[] =
         {"set_costs", astar_setcosts},
         {"set_map", astar_setmap},
         {"setup", astar_setup},
+        {"get_at", astar_get_at},
+        {"set_at", astar_set_at},
         {0, 0}
 
 };