vkgears: use a semaphore per frame
This allows us to avoid acquiring an image with a signaled semaphore without limiting the number of in-flight frames to one.
This is an alternative approach to what the first patch in !178 does.
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This allows us to avoid acquiring an image with a signaled semaphore without limiting the number of in-flight frames to one.
This is an alternative approach to what the first patch in !178 does.