I'm studying about collision detection in 3d world but it really confused actually why we using 3d grid cells in 3d world.
If we think the world looks like 'minecraft', it will be efficient but our real world doesn't fit well in 3d grid cells(different shape of objects..).
So my question is this:
1) Why we use 3d grid cells?
2) Is 3d grid cells really efficient while performing 3d simulation?
3) What does it mean 'different 3d grid cells'? Just different size of grid?
Thanks!