Live C++ coding: a vulkan engine. Please read description!

Current stream:

Yesterday I got working: two pipeline factories, each having a single characteristic and creating a single pipeline (no range). I think I can consider the "open brain surgery" to be finished and will merge the branch 'brain' into 'master'.

Todo: Currently we have multiple pipelines (P), created by multiple pipeline factories (F) that exist of multiple pipeline (factory) characteristics (C) each of which can span a range (0...Rc) where user defined "descriptors" (called shader resources), linked to a consecutive subrange of a characteristic range of one or more pipeline factories, can represent an array of combined-image-samplers. The user can then update section of that array with an array of Texture's, causing those textures to become visible on one or more vertex faces (triangles) in the scene... Clearly this needs more than words to be made clear. Moreover, I need a test application to play with this so I can test if all related code works.

Todo: Textures (images) are "uploaded" to the GPU now - but what does that mean? What represents the CPU-side thing(s) that allows me to use a texture? And how can I free the resources on the GPU again when I don't need the texture anymore?

Todo: Properly fix uploading vertex buffers so that that is only done once.

FAQ
Q: What is a vulkan engine?
A: a graphics program that uses the Vulkan API (a library+driver that talks directly to the GPU). An engine is a bunch of functions that do complex tasks so that you can use vulkan with a simpler syntax.
Q: What editor are you using?
A: nvim 0.8.0 - inside a (true color) terminal (konsole) using font DejaVu Sans Mono 16pt and syntax coloring as per https://github.com/CarloWood/neovim-true-color-scheme-editor
Q: How long have you been coding?
A: I started at 12 on a TRS-80 in a shop where they sold those. Later my dad bought a D.A.I. (2 Mhz clk, 48 kB ram) on which I taught myself to code in GFA-basic and assembly and little C (although that usually crashed the whole OS). I started to code seriously in C once CPUs had 'proctected mode' that allows safe multi-tasking at the age of 25. I only started with C++ when I left university at the age of 30. I am now 58 - so that means I've been coding C++ for 28 years (full time).

Note: Each Todo is followed by the Todo that I was working on. The higher Todo's need to be finished before I can continue with a lower Todo.

The source code of this project is Free Open Source (GPL3). The git repository can be found here: https://github.com/CarloWood/linuxviewer