XrInstanceCreateInfo

XrInstanceCreateInfo is a structure used by the OpenXR runtime to create an OpenXR instance through the xrCreateInstance function. It specifies application metadata, the OpenXR API version to target, and which extensions to enable for the instance. The information provided here is used by the runtime to initialize the OpenXR environment for the application.

The structure typically includes fields such as type, next, applicationInfo, enabledApiVersion, and a list of enabled extension names. The type must be XR_TYPE_INSTANCE_CREATE_INFO, and the next pointer is used to chain extension-specific data structures if supported by the runtime. applicationInfo points to an XrApplicationInfo structure that describes the application name, engine name, and version numbers. The api version field indicates the OpenXR API version the application intends to use, commonly specified with a macro like XR_MAKE_VERSION. The enabled extension names field (often accompanied by a count) lists the OpenXR extensions to enable for this instance; the runtime validates these against supported extensions and may reject the creation if required extensions are unavailable.

Opening or enabling extensions may influence which features are available at runtime, and some extensions may be required for certain functionality. If the extension chain in next contains extension-specific create-info structures, these can enable additional capabilities during instance creation. If enabled extensions are too restrictive or unsupported, xrCreateInstance may return an error such as XR_ERROR_EXTENSION_NOT_PRESENT or XR_ERROR_FORM_FACTOR_UNSUPPORTED, among others.

In practice, developers prepare an XrApplicationInfo with app and engine details, set the desired API version, optionally specify extensions, and pass a pointer to the XrInstanceCreateInfo to xrCreateInstance. A successful call yields an XrInstance handle to be used for subsequent OpenXR operations.