2D CAD for open GL

Are there any kind of FREE DOWNLOADING 2D CAD program that can convert C++ Language in combination with OpenGL?
Why? It took me a month to browse around for a tutorial explaining how to make a circle, line, triangle or square or such polygons using C++ codes in combination with openGL. Nor how to rotate it. And also,there isn’t any tutorial explaining how to set up text/number at refresh rate on every changing values (if networked via game program).
For clarification. My intention on working with project on driving simulation. What I wanted to have is the server working via client(s). The server would have driving simulation program installed, and if I could find some help and create .exe with knowledge of codes i could have it installed in client which would display as speedometer “instrument panel.”
So at the point, if there isn’t any libraries or tutorial on flat polygons or refreshing texture at value change. I thought maybe there are some 2D CAD programs that I could download it for free. Maybe I could use mouse to expand flat polygon and it would automatically write C++ codes. In other way, it’s good to learn what codes are when creating flat polygons. After creating polygons, I could probablly color it or add textures on it. Then I could compile it run it.
Or are there any other suggestion that you might want to share with me regarding to what I am looking for? Let me know…


I don’t think the advanced forum is the place to look for tutorials on rotating 2D polygons. I see you’ve crossposted too, so I’ll close this thread.

– Tom