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GameMaker Studio 2 Destructible Terrain

An example of collidable, destructible terrain in GameMaker Studio 2 using surfaces and grids.

Why Grids?

Unlike using the sprite as a collision mask, using grids allows you to process collisions whilst the sprite is un-rendered. This is partically useful when you want to render a large destructible arena or have sections of the arena off-screen.

If you wish to keep it small and simple however, it would probably be wiser to just use sprite collisions instead. This example project does not cover this.