How to determine the topmost object in a 2D projection of a 3D object?

Question

I have a surface on which a set of three-dimensional objects is drawn. The task is to determine the object by the given coordinates on the surface.

For example: some objects are drawn on a desktop application, I need to determine which object the user clicked on.

Could you advise how such tasks are usually solved? Do I need to create remember the topmost object for each pixel? I do not think this is the best approach.

Any thoughts are welcome!

Thank!

Answer 1

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Answer 2

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