Room width

Explanation
This variable holds the width of the entire room (you need to use to get the size of the view inside the room). This variable is read-only, you cannot use this function to change the size of the room.

Example
// Create an object at the right hand side of the room (room_width,100,obj_player); In the example above, as you're using room_width, no matter what size the room is, the object will always be placed at the right-hand side. You can also use room_width to center objects on screen. First, make sure the origins of the object is in the center then you divide room_width by 2: // Create and center the object horizontally in the room (room_width/2,100,obj_player);