LLGL::XRSystem Class Reference

XR system interface. More...

#include <XRSystem.h>

Inheritance diagram for LLGL::XRSystem:

Public Member Functions
	~XRSystem ()
	Releases internal data.
virtual const char *	GetRuntimeName () const =0
	Returns the runtime name reported by the active OpenXR runtime (e.g. "SteamVR" or "Monado").
virtual ArrayView< XRViewConfigurationView >	GetViewConfigurations () const =0
	Returns the view configuration entries for the form factor selected at load time.
virtual const Report *	GetReport () const =0
	Returns a pointer to the report or null if there is none.
virtual RenderSystemPtr	CreateRenderSystem (const RenderSystemDescriptor &renderSystemDesc, Report *report=nullptr)=0
	Creates an LLGL::RenderSystem whose underlying graphics device satisfies the XR runtime's binding requirements.
virtual XRSession *	CreateSession (const XRSessionDescriptor &sessionDesc, RenderSystem &renderSystem)=0
	Creates a new XR session bound to the given render system.
virtual void	Release (XRSession &session)=0
	Releases the specified session. After this call, the session must no longer be used.
virtual bool	PollEvents ()=0
	Polls the OpenXR runtime for events.
virtual bool	GetNativeHandle (void *nativeHandle, std::size_t nativeHandleSize)=0
	Returns the native handle of this XR system.
Public Member Functions inherited from LLGL::Interface
virtual bool	IsInstanceOf (int id) const
	Returns true if this object is an instance of the specified interface.
Public Member Functions inherited from LLGL::NonCopyable
	NonCopyable (const NonCopyable &)=delete
NonCopyable &	operator= (const NonCopyable &)=delete
virtual	~NonCopyable ()=default

Static Public Member Functions
static XRSystemPtr	Load (const XRSystemDescriptor &xrSystemDesc, Report *report=nullptr)
	Loads and brings up an XR runtime.
static void	Unload (XRSystemPtr &&xrSystem)
	Unloads the specified XR system.

Protected Member Functions
	XRSystem ()
	Allocates the internal data.
Protected Member Functions inherited from LLGL::NonCopyable
	NonCopyable ()=default

Detailed Description

XR system interface.

Remarks

Top-level entry point for OpenXR support. An XRSystem brings up the XR runtime, queries the selected device's view configuration, and prepares an LLGL::RenderSystem whose underlying graphics device satisfies the runtime's binding requirements.

Typical usage:

// 1. Bring up XR runtime
LLGL::XRSystemDescriptor xrDesc;
xrDesc.applicationName = "MyApp";
LLGL::XRSystemPtr xr = LLGL::XRSystem::Load(xrDesc);
 
// 2. Create an XR-compatible renderer
LLGL::RenderSystemDescriptor rDesc;
rDesc.rendererModule = "Vulkan";
LLGL::RenderSystemPtr renderer = xr->CreateRenderSystem(rDesc);
 
// 3. Create an XR session bound to that renderer, then per-view swap-chains
LLGL::XRSession* session = xr->CreateSession(LLGL::XRSessionDescriptor{}, *renderer);
const auto views = xr->GetViewConfigurations();
//...

See also

XRSession

XRSwapChain

Constructor & Destructor Documentation

~XRSystem()

LLGL::XRSystem::~XRSystem

(

)

Releases internal data.

XRSystem()

LLGL::XRSystem::XRSystem ( )

protected

Allocates the internal data.

Member Function Documentation

CreateRenderSystem()

virtual RenderSystemPtr LLGL::XRSystem::CreateRenderSystem ( const RenderSystemDescriptor & renderSystemDesc, Report * report = nullptr )

pure virtual

Creates an LLGL::RenderSystem whose underlying graphics device satisfies the XR runtime's binding requirements.

Parameters

[in]	renderSystemDesc	Specifies the render system descriptor.
[out]	report	Optional pointer to a report on failure.

Returns

Unique pointer to a render system, or null on failure.

Remarks

Supported renderer modules are "Vulkan", "Direct3D11", and "Direct3D12". The returned render system must be used as the renderer parameter to CreateSession.

See also

RenderSystemDescriptor

CreateSession()

virtual XRSession * LLGL::XRSystem::CreateSession ( const XRSessionDescriptor & sessionDesc, RenderSystem & renderSystem )

pure virtual

Creates a new XR session bound to the given render system.

Parameters

[in]	sessionDesc	Specifies the XR session descriptor.
[in]	renderSystem	The renderer to bind the session to. Must have been obtained from CreateRenderSystem on this same XRSystem instance.

Returns

Pointer to the new XRSession, or null on failure.

Remarks

Ownership of the session remains with the XRSystem; use Release to free it.

GetNativeHandle()

virtual bool LLGL::XRSystem::GetNativeHandle ( void * nativeHandle, std::size_t nativeHandleSize )

pure virtual

Returns the native handle of this XR system.

Parameters

[out]	nativeHandle	Pointer to the backend-specific native handle structure. Obtain it from #include <LLGL/Backend/OpenXR/NativeHandle.h>.
[in]	nativeHandleSize	Size (in bytes) of the native handle structure.

Returns

True if the native handle was successfully retrieved.

See also

OpenXR::SystemNativeHandle

GetReport()

virtual const Report * LLGL::XRSystem::GetReport ( ) const

pure virtual

Returns a pointer to the report or null if there is none.

GetRuntimeName()

virtual const char * LLGL::XRSystem::GetRuntimeName ( ) const

pure virtual

Returns the runtime name reported by the active OpenXR runtime (e.g. "SteamVR" or "Monado").

GetViewConfigurations()

virtual ArrayView< XRViewConfigurationView > LLGL::XRSystem::GetViewConfigurations ( ) const

pure virtual

Returns the view configuration entries for the form factor selected at load time.

Remarks

The returned array's size is the number of views the application must render each frame (e.g. 2 for stereo). Each entry carries recommended and maximum image dimensions plus sample counts.

Load()

XRSystemPtr LLGL::XRSystem::Load ( const XRSystemDescriptor & xrSystemDesc, Report * report = nullptr )

static

Loads and brings up an XR runtime.

Parameters

[in]	xrSystemDesc	Specifies the XR system descriptor.
[out]	report	Optional pointer to a report on failure of loading the XR runtime.

Returns

Unique pointer to the new XR system, or null on failure (in which case report is populated if provided).

Remarks

This function discovers the active OpenXR runtime via the OpenXR loader and queries the selected form factor. Returns null if no compatible runtime is installed or the requested form factor is unavailable.

PollEvents()

virtual bool LLGL::XRSystem::PollEvents ( )

pure virtual

Polls the OpenXR runtime for events.

Remarks

Must be called regularly from the main loop; this drives session-state transitions reported through XRSession::GetState. Returns true if any events were processed.

Release()

virtual void LLGL::XRSystem::Release ( XRSession & session )

pure virtual

Releases the specified session. After this call, the session must no longer be used.

Unload()

void LLGL::XRSystem::Unload ( XRSystemPtr && xrSystem )

static

Unloads the specified XR system.

Remarks

After this call, all sessions and swap-chains created from this system must no longer be used.

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The documentation for this class was generated from the following file:

• XRSystem.h