Question

I’m trying to improve my game’s rendering by bulk rendering the textures of blocks of the same type.

Each block in my game is defined by a class in the format BlockWood, which all extend from the class Block.

I currently have a map between the different block classes/types, and an ArrayList which contains the positions of all the blocks of that type, on the map.

HashMap<Block, ArrayList<Vector2f>> blockMap = new HashMap<Block, ArrayList<Vector2f>>();

Using this, I can loop through the map, bulk rendering each type of block, speeding up my rendering.

This approach however, doesn’t work. I want to be able to access the ArrayList’s using a dummy class as so –

blockMap.get(BlockWood.class);

Is there any efficient way I can map a class type to an ArrayList? Or will I just have to map the class string representations?

Answer 1

You want to use Class as the key type. Your current implementation is using a Block instance as the key. Where as using Class will use the type of Block as the key.