OpenGL: Where is the front, where is the back?

For 3D models - not a trivial question by the way.

When talking about ourselves or human being in general, our natural assumption is that the right side is to the right of the BACK, not of the front. To the right of the front is LEFT hand:

The same applies to cars:

However, this is a LEFT handed coordinate system !

A quick reminder just in case:

But OpenGL is RIGHT handed !

Some could say: what a stupid decision to use right handed system?!

Well… It is NOT "stupid".

In real life we use BOTH. For example, when looking at buildings, we rely on RIGHT handed system where the right side is to the right of the FRONT:

Both systems work. For example, MS in their DirectX choose to use the left handed. But since we picked OpenGL, let's follow THEIR standard. So, correct orientation in our case would be:

Like for buildings, not like for cars or people.


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