This commit fixes issues that prevented clang-cl & clang from being distinguished
on windows, resulting in improper command line arguments being used.
CMAKE_CXX_COMPILER_FRONTEND_VARIANT is the proper way to distinguish clang from
clang-cl, which have different command line options.
Adds extensive integration tests that exercise the various ways of finding
the Vulkan-Headers.
vk-bootstrap should now use the Vulkan-Headers or Vulkan::Headers targets if
they were already defined (such as is the case of FetchContent), and will
look for the VulkanHeaders package and Vulkan package as a fallback, and will
FetchContent Vulkan-Headers directly if that fails.
This should make integration seamless with the various ways vulkan-headers
is acquired.
The vk-bootstrap-vulkan-headers target was dropped in favor of directly
linking to Vulkan-Headers (creating a target by that name if none exists).
Previously, tests would always be enabled if the repo was the top
level project, which isn't desireable for users. This alters the logic
to, by default, only enabling tests when its a top level project, but
still allowing users to *not* enable tests by setting VK_BOOTSTRAP_TEST
to off.
find_package is used to try to find the Vulkan-Headers, and if they aren't
present, it downloads them with fetch content. This way users don't need
vulkan 'installed' on their system, specifically for windows users.
It also changes the tests to load all the necessary function pointers, that
way we don't need to find the vulkan loader to build the tests.
Make vk-bootstrap capable of loading the vulkan runtime and not need to
link against the library. This improves the usability of vk-bootstrap since
now you don't need the vulkan library on your system to build.
This commit also changes how SystemInfo works so as to allow the dynamic
vulkan loading.
SystemInfo will be the way for users to know what is and isn't available on their system.
Currently, it only has booleans for if validation layers and debug messenger are available,
but more could be added in the future.
Now there is a concise example of the library in use all the way to presenting.
Needs to be rewritten to remove exceptions, but for first pass its good enough.
Library contains barebones implementations for simplified
Instance creation
Physical Device selection
Device creation
Swapchain Creation/Recreation
Much of the repo is WIP, and there is little to no testing.
Also, while a single header file is desired for the future, currently
it is structured more like a normal project with .cpp files
