[shader-slang] Add cmake targets about vcpkg

[jimwang118]

Shader-slang directly downloaded the release version without source code for compilation, so no cmake usage was generated. If you want to use it in cmake, you can use find_path and find_library to find header files and calling libraries.

[dg0yt]

I assume there is something in the vcpkg portfile functions to define a cmake target.

No. Portfiles are just vcpkg scripting, not using CMake project mode.

maybe it is possible to be configured to use the cmake directly that is part of the regular github repo.

Not easily: there is a number of vendored, and possibly patched, dependencies. This needs work.

And AFAICS upstream's CMake doesn't install a CMake config package.

https://github.com/search?q=repo%3Ashader-slang%2Fslang+export+language%3ACMake&type=code&l=CMake
https://github.com/search?q=repo%3Ashader-slang%2Fslang%20SlangTargets&type=code

[jimwang118]

Thanks for posting this issue. Please reopen this issue if this is still a problem for you.