C Specification

XR_DEFINE_HANDLE(XrSwapchain)

Description

Normal XR applications will want to present rendered images to the user. To allow this, the runtime provides images organized in swapchains for the application to render into. The runtime must allow applications to create multiple swapchains.

Swapchain image format support by the runtime is specified by the xrEnumerateSwapchainFormats function. Runtimes should support R8G8B8A8 and R8G8B8A8 sRGB formats if possible.

Swapchain images can be 2D or 2D Array.

Rendering operations involving composition of submitted layers should be assumed to be internally performed by the runtime in linear color space. Images submitted in sRGB color space must be created using an API-specific sRGB format (e.g. DXGI_FORMAT_R8G8B8A8_UNORM_SRGB, GL_SRGB8_ALPHA8, VK_FORMAT_R8G8B8A8_SRGB) to apply automatic sRGB-to-linear conversion when read by the runtime. All other formats will be treated as linear values.

Note

OpenXR applications should avoid submitting linear encoded 8 bit color data (e.g. DXGI_FORMAT_R8G8B8A8_UNORM) whenever possible as it may result in color banding.

Gritz, L. and d’Eon, E. 2007. The Importance of Being Linear. In: H. Nguyen, ed., GPU Gems 3. Addison-Wesley Professional. https://developer.nvidia.com/gpugems/gpugems3/part-iv-image-effects/chapter-24-importance-being-linear

Note

DXGI resources will be created with their associated TYPELESS format, but the runtime will use the application-specified format for reading the data.

See Also

Document Notes

For more information, see the OpenXR Specification

This page is extracted from the OpenXR Specification. Fixes and changes should be made to the Specification, not directly.

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