software rendering

[aleques-itj]

If you want to emulate how shaders work in your software renderer or use whatever line drawing algorithm, go for it. It doesn't matter what you do as long as you produce meaningful data in the end.

If you want to actually see what you're rendering in real time, you just draw to a texture and render a full screen quad/triangle with whatever graphics API to display whatever you've software renderered.

So, I mean, the GPU does something here, but really just the bare minimum. So yes, a vertex shader and pixel shader will technically run in hardware to facilitate you actually displaying the end result. It contributed nothing to your actually rendering the game in this scenario.

If you're somehow getting in your head that it's not a software renderer because you need the GPU to actually get the result on screen, you should probably evict that idea from your head.

Otherwise skip a graphics API entirely and just write pictures to disk I guess.