* For the most part we implement this as a thin pass-through layer. Where we
care about things (image barriers for layout transitions and queue
submissions) we do two different things:
- For image barriers, we "downcast" to plain VkImageMemoryBarrier. Currently
the only thing that's unique to VkImageMemoryBarrier2KHR is extra access
flags and pipeline stages, which we don't care about. This keeps a lot of
code from having to either handle two paths or handle the new path and then
do lots of conversions back to VkImageMemoryBarrier when running on older
drivers.
- For queue submissions we do the opposite. We promote old VkSubmitInfo to
VkSubmitInfo2KHR and process that in a common function, then if necessary
we decay back to VkSubmitInfo before sending to the driver.
* This helps catches cases where a discarded image is accidentally used and in
many cases may still have valid data. Particularly on Vulkan this is relevant
for DONT_CARE renderpass load and store ops.
* Instead of tracking their lifetime with that object, we move the lifetime
tracking into the parent VulkanGraphicsTest and destroy them all at the end. A
single handle can optionally be free'd on its own.
* This will let us run multiple windows (and multiple threads) relatively
easily.
* The hammer is fairly big, we move some things into the window that don't need
to be there necessarily if we have multiple windows on a single thread, but it
keeps things simple.
* Instead of only doing a very lightweight check to see if the API is available
up-front, we now share the API initialisation among all API tests far enough
to determine availability of extensions, features, etc. Then we can precisely
determine which tests are available and which aren't before running.
* We also fix a number of issues that could cause incorrect formats to be
generated.
* Test cases added for D3D11/GL/Vulkan to test different struct types. These
aren't automated at the moment because most of the code they're testing is in
the UI itself.
baldurk