In this video all the destruction, which was previously drawn. If someone played Worms 3D, we saw how they destroyed the map. This is done by the method of minecraft + sglazhivanie the edges and boundaries of textures.
Here's a 2D analogue:
1. Create a map out of blocks
2. We need the centers of these cubes
3. On them now will work
4. Apply a suitable smoothing algorithm
5. Draw what happened
And in contact with the projectile, you need to remove a certain number of cubes or just redraw the map