Week 3 - Drag and drop

I have finished the Drag-and-drop system for the first tower in the game, this should be easily transferable to other towers. At first I only implemeted a drag and drop system for mobile phones but to make testing easier I added a drag and drop system to be usable with a mouse too. So far the player can sucessfully drag a sprite of a tower onto the map and it will instantiate a new instance of said tower where the player dropped it, apart from roads where I added colliders to delete the tower if a player tries to place it on them.