As someone who's kinda hovered around graphics land but never really stepped foot into it, it's pretty difficult to determine what Vulkan represents. Is it going to replace OpenGL? If I'm going to start learning graphics for the first time, would it still be useful to start with OpenGL or should I just dive into Vulkan?

Vulkan represents a low-level way of talking to the GPU more or less on the GPU's terms. As opposed to OpenGL which is a way of talking to the GPU on boomer CAD programmers' terms.

As for whether Vulkan is going to replace OpenGL... yes and no. Over the next 10 or so years we may see OpenGL drivers for GPUs get replaced with Vulkan drivers plus an OpenGL layer based on Vulkan. But you will still be able to develop to OpenGL.

Ad for what you should start with... what do you plan on doing? If you're looking to write a game, use a widely available engine like Unreal or Godot that abstracts the graphics library details. If you're looking to write your own engine... seriously, seriously reconsider.

If you're still interested in programming immediate-mode graphics below the engine layer, start with DirectX 11 and 12. They're much more tractable than OpenGL and Vulkan and have unbeatable tooling support from Microsoft. Even if you're targeting Linux, you will have much more binary compatibility across distros by shipping it as a Windows program and running it under Wine.

"Vulkan represents a low-level way of talking to the GPU more or less on the GPU's terms. As opposed to OpenGL which is a way of talking to the GPU on boomer CAD programmers' terms."

Kind of like that description. I've been doing GL since before it was OpenGL.

In my Common Lisp 3D system [1], I've been happily using very simple immediate mode OpenGL calls, taking advantage of CAD-like features such as drawing wireframes of various thickness over shaded polygons. OpenGL provides specific Z-buffer API calls to facilitate such things.

Is there a simple way of doing such CAD-centric things in Vulkan?

[1] https://github.com/kaveh808/kons-9