SurfaceCapabilities invariability

[krOoze]

In one of the recent updates it was specified the results from all query commands are by default kept true for the duration of the lifetime of the parameters.

I want to ask if this is intended for vkGetPhysicalDeviceSurfaceCapabilitiesKHR too, which doesn't seem to have "lifetime" of its result otherwisely specified.

That would imply VkSurfaceKHR is no longer valid and would have to be recreated on suspected change of parameters (e.g. on VK_ERROR_OUT_OF_DATE_KHR and window size change). Which doesn't seem intended (with VK_ERROR_SURFACE_LOST_KHR also existing).

On the other hand if the results can change any time arbitrarily, Application could not be capable to adhere to Valid Usage of VkSwapchainCreateInfoKHR, which require the App to restrict some of its parameters to match the result from vkGetPhysicalDeviceSurfaceCapabilitiesKHR.

EDIT: I assume result of vkGetPhysicalDeviceSurfacePresentModesKHR() and vkGetPhysicalDeviceSurfaceFormatsKHR() never changes, otherwise same problem.

[jjulianoatnv]

Thank you for this feedback. You raise a good question. We began discussing within Khronos.

[krOoze]

@jjulianoatnv Any news?

BTW I also noticed this:

Some Vulkan functions may send protocol over the specified Xlib Display connection when using a swapchain or presentable images created from a VkSurfaceKHR referring to an Xlib window.

and similarly for other platforms. But vkGetPhysicalDeviceSurfaceCapabilitiesKHR is not a swapchain command, though Mesa seems to use the connection.

Which I guess means the value can change at any arbitrary time.