Creating vector shapes using only C++ I've been researching for quite a while and I couldn't find any explanation or at least a how to create a vector graphic application (specifically in windows) where I can create a 3D vector shape, say a box. I know there is OpenGL and DirectX for that and the new Vulkan API but I don't wan't to use those APIs and libraries. What I am asking is where can I find examples or at least tutorials for creating custom made API graphics library for the C++ language. If there is not a way in C++ language then any other way to do it. By example masm or nasm Assembly language.

If my question is too broad please specify any additional information you need to be able to answer my question.
What you are looking for is a way to get access to individual pixels in an image, in a way that you can modify those pixels with CPU code.

Once you have that you'll want to find software rendering / software rasterization methods.

A great place to start would be reading up in the various bresenham algorithms.

There is a lot of info out there on that. Here is one article for instance:
http://blog.demofox.org/2015/01/17/bresenhams-drawing-algorithms/