https://dev.opencascade.org/ may be interesting for you.

@timob256 I entered "Qt Quick draw line" in Google and got this: https://doc.qt.io/qt-5/qml-qtquick-pathline.html

Alright,
with much time and an extensive amout of google search I managed to cobble a working QOpenGLWidget program together.

I used this official Qt-Example as a basline:
http://doc.qt.io/qt-5/qtopengl-cube-example.html

here is the combination with my Tesseract code
https://github.com/DeiVadder/Tesseract-Challenge-OpenGL

It's working, yeah me!!, but I have the feeling that it's far from ideal. I'm just glad I managed to draw something in 3d.

Anyway, closed and solved.

@Ankit.Jain To put best efforts to your key functionalities will be better.

Try to triangulate faces of your mesh (select your shape, switch to Edit Mode and press Ctrl+T ).

Hi and welcome to devnet,

The usual combo is currently QML for the UI and C++ for the business logic. What industry are you targeting ?