Hidden-surface determination

Hidden-surface determination is like playing hide-and-seek with your toys. Imagine you have a lot of toys in your room, and you want to find a specific toy behind all the other ones. But you can't just see through them, so you have to move the toys around to find the one you want.

Now imagine the toys are 3D objects in a computer game or animation. Computers can't see through objects either, so they need to figure out which objects should be shown in the scene and which ones should be hidden (just like you want to find the specific toy).

To do this, the computer uses math and algorithms to determine which objects are in front of other ones. It's like peeking through the gaps between the toys to see which ones are closest and which ones are further away.

Once the computer figures out which objects should be hidden, it can then remove them from the scene or make them transparent, so you can see the objects that you're supposed to see without being confused by the ones that you're not supposed to see.

And that's basically how computers determine which objects should be hidden in a 3D scene – by using math and algorithms to figure out which ones are behind other ones.