How to represent a 3D .obj object as a 3D array?

Is there any way by which 3D models can be represented as 3D arrays? Are there any libraries that take .obj or .blend files as input and give an array representation of the same?

I thought that I would slice object and export the slices to an image. I would then use those images in opencv to build arrays for each slice. In the end I would combine all the arrays of all the slices to finally get a 3D array representation of my .obj file. But I gave up halfway through because it is a painfully long process to get the image slices aligned to each other.

Is there any other index based representation I could use to represent 3D models in code?

A 3D array would be very convenient for my purposes.