[kruseborn]

In vulkan the viewport is upside down and you can change that by having a negative viewport height. The device extension VK_KHR_MAINTENANCE1 or VK_AMD_NEGATIVE_VIEWPORT_HEIGHT has to be enabled.

Is this something that moltenVK supports?

[Bill Hollings]

@kruseborn

MoltenVK does not currently directly support either of those extensions.

However, the Vulkan VkViewport information is passed directly to the Metal MTLViewport…which does allow flipping.

Have you tried it? Does providing a negative height in VkViewport to MoltenVK perform the flipping that you expect?

…Bill

[kruseborn]

It looks like it is working, I get not errors from the Metal framework and the picture is correct:)

[Bill Hollings]

@kruseborn

Thanks for reporting back your results. I’m glad it worked for you.

Based on your feedback…for the next MoltenVK release…I’ve added VK_AMD_negative_viewport_height to the list of supported extensions reported by the MoltenVK driver…and in the MoltenVK documentation.

…Bill

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