Open Inventor

Hello,

I have seen some videos about Open Inventor.

I’m still confused and don’t know what Open Inventor Api is? it says “Opengl Toolkit” i know Opengl by itself is the API and glut for example is opengl toolkit for windowing etc… what is open inventor? what it does? do we need to use opengl first in order to use it?

Open Inventor is a scene graph library layered on top of OpenGL. It provides higher-level semantics for 3D rendering using OpenGL to render.