Please add DirectX 11 support

[ThePixelMoon]

Is your feature request related to a problem? Please describe.
The problem is, DirectX 9 is way too old, and this project's purpose is to modernize.
EDIT: Probably not modernizing, but something in-between.

Describe the solution you'd like
Just adding DirectX 11 or even 10 would completely modernize the engine.

Describe alternatives you've considered
There is also Vulkan, but not everyone's PC can handle it. Would be nice to keep DirectX 9 as a command-line parameter tho, for example, compatibility.

[dimhotepus]

Yep, I have plans to do so.

For example Strata Source did so https://developer.valvesoftware.com/w/index.php?title=Strata_Source

Nice things are:

1. ~30% performance boost due to less DirectX runtime overhead.
2. Modern GPU debugging and tracing tools, as DirectX 9 debugging aren't supported since Windows 7.
3. More features like tesselation, geometry and computation shaders, etc.

The main problem is shaders as they all should rewritten to sm 5.

I have a basic DirectX 11 implementation here:
https://github.com/Source-Authors/Obsoletium/tree/master/materialsystem/shader_api_dx11

But there are a lot more things to add.

[ThePixelMoon]

The main problem is shaders as they all should rewritten to sm 5.

Maybe make a compatibility-layer type of thingy like ToGL does?

[dimhotepus]

The main problem is shaders as they all should rewritten to sm 5.

Maybe make a compatibility-layer type of thingy like ToGL does?

It is possible.
But ToGL layer has its own bugs, I'm afraid new compat layer will add own ones.

It is possible to use DirectX9_3 feature level on DirectX11 hardware, but last time I've checked it had some strange things like GPU with native DirectX9 sm 3 support some things which DirectX9_3 feature level doesn't :). According to StackOverflow it is fine as emulation has its own laws.

[rwf93]

snip
The main problem is shaders as they all should rewritten to sm 5.

I have a basic DirectX 11 implementation here: https://github.com/Source-Authors/Obsoletium/tree/master/materialsystem/shader_api_dx11

But there are a lot more things to add.

Quiver did quite a few ports to SM4.0 years ago with DX11 support. A while ago, I managed to port parts of that code into nillerusr's codebase (which is not too distant from this project), as well as update some of the code to compile with SM5.0 (particularly fixed preproc macros relating to SM4.0).

I will add however, there is major issues with texture loading and rendering (particularly mipmaps). On top of this, alpha testing is basically completely broken. I am not sure of the reason behind it and attempted to debug further in RenderDoc. Which yielded no result in figuring out what was causing the issues. Though, I speculate it to be an issue with sampler state in relation to cubemaps.

You can view some of the changes here.

I did eventually have some plans to port the existing shader code to shader-slang for better interoperability, particularly if in the future I wanted to implement another graphics API cough Vulkan cough in the future.

If you want, I can also send some screenshots of the progress so far.