#include <qrhinull_p.h>

Inheritance diagram for QNullSwapChain:

Collaboration diagram for QNullSwapChain:

Public Member Functions
	QNullSwapChain (QRhiImplementation *rhi)

	~QNullSwapChain ()

void	destroy () override
	Releases (or requests deferred releasing of) the underlying native graphics resources.

QRhiCommandBuffer *	currentFrameCommandBuffer () override

QRhiRenderTarget *	currentFrameRenderTarget () override

QSize	surfacePixelSize () override

bool	isFormatSupported (Format f) override

QRhiRenderPassDescriptor *	newCompatibleRenderPassDescriptor () override

bool	createOrResize () override
	Creates the swapchain if not already done and resizes the swapchain buffers to match the current size of the targeted surface.

Public Member Functions inherited from QRhiSwapChain
QRhiResource::Type	resourceType () const override

QWindow *	window () const

void	setWindow (QWindow *window)
	Sets the window.

QRhiSwapChainProxyData	proxyData () const

void	setProxyData (const QRhiSwapChainProxyData &d)
	Sets the proxy data d.

Flags	flags () const

void	setFlags (Flags f)
	Sets the flags f.

Format	format () const

void	setFormat (Format f)
	Sets the format f.

QRhiRenderBuffer *	depthStencil () const

void	setDepthStencil (QRhiRenderBuffer *ds)
	Sets the renderbuffer ds for use as a depth-stencil buffer.

int	sampleCount () const

void	setSampleCount (int samples)
	Sets the sample count.

QRhiRenderPassDescriptor *	renderPassDescriptor () const

void	setRenderPassDescriptor (QRhiRenderPassDescriptor *desc)
	Associates with the QRhiRenderPassDescriptor desc.

QSize	currentPixelSize () const

virtual QRhiRenderTarget *	currentFrameRenderTarget (StereoTargetBuffer targetBuffer)

virtual QRhiSwapChainHdrInfo	hdrInfo ()
	\variable QRhiSwapChainHdrInfo::limitsType

Public Member Functions inherited from QRhiResource
virtual	~QRhiResource ()
	Destructor.

void	deleteLater ()
	When called without a frame being recorded, this function is equivalent to deleting the object.

QByteArray	name () const

void	setName (const QByteArray &name)
	Sets a name for the object.

quint64	globalResourceId () const

QRhi *	rhi () const

Public Attributes
QWindow *	window = nullptr

QNullSwapChainRenderTarget	rt

QNullCommandBuffer	cb

int	frameCount = 0

Additional Inherited Members
Public Types inherited from QRhiSwapChain
enum	Flag { SurfaceHasPreMulAlpha = 1 << 0 , SurfaceHasNonPreMulAlpha = 1 << 1 , sRGB = 1 << 2 , UsedAsTransferSource = 1 << 3 , NoVSync = 1 << 4 , MinimalBufferCount = 1 << 5 }
	Flag values to describe swapchain properties. More...

enum	Format { SDR , HDRExtendedSrgbLinear , HDR10 , HDRExtendedDisplayP3Linear }
	Describes the swapchain format. More...

enum	StereoTargetBuffer { LeftBuffer , RightBuffer }
	Selects the backbuffer to use with a stereoscopic swapchain. More...

Public Types inherited from QRhiResource
enum	Type { Buffer , Texture , Sampler , RenderBuffer , RenderPassDescriptor , SwapChainRenderTarget , TextureRenderTarget , ShaderResourceBindings , GraphicsPipeline , SwapChain , ComputePipeline , CommandBuffer }
	Specifies type of the resource. More...

Protected Member Functions inherited from QRhiSwapChain
	QRhiSwapChain (QRhiImplementation *rhi)

Protected Member Functions inherited from QRhiResource
	QRhiResource (QRhiImplementation *rhi)

Protected Attributes inherited from QRhiSwapChain
QWindow *	m_window = nullptr

Flags	m_flags

Format	m_format = SDR

QRhiRenderBuffer *	m_depthStencil = nullptr

int	m_sampleCount = 1

QRhiRenderPassDescriptor *	m_renderPassDesc = nullptr

QSize	m_currentPixelSize

QRhiSwapChainProxyData	m_proxyData

Protected Attributes inherited from QRhiResource
QRhiImplementation *	m_rhi = nullptr

quint64	m_id

QByteArray	m_objectName

Detailed Description

Definition at line 151 of file qrhinull_p.h.

Constructor & Destructor Documentation

◆ QNullSwapChain()

QNullSwapChain::QNullSwapChain ( QRhiImplementation * rhi )

Definition at line 975 of file qrhinull.cpp.

◆ ~QNullSwapChain()

QNullSwapChain::~QNullSwapChain ( )

Definition at line 982 of file qrhinull.cpp.

References destroy().

Here is the call graph for this function:

Member Function Documentation

◆ createOrResize()

bool QNullSwapChain::createOrResize ( )

overridevirtual

Creates the swapchain if not already done and resizes the swapchain buffers to match the current size of the targeted surface.

Call this whenever the size of the target surface is different than before.

Note: call destroy() only when the swapchain needs to be released completely, typically upon QPlatformSurfaceEvent::SurfaceAboutToBeDestroyed. To perform resizing, just call createOrResize().

Returns: true when successful, false when a graphics operation failed. Regardless of the return value, calling destroy() is always safe.

Implements QRhiSwapChain.

Definition at line 1022 of file qrhinull.cpp.

References QNullSwapChainRenderTarget::d, destroy(), frameCount, QRhiSwapChain::m_currentPixelSize, QRhiSwapChain::m_renderPassDesc, QRhiSwapChain::m_window, QNullRenderTargetData::pixelSize, QRHI_RES, QRHI_RES_RHI, QNullRenderTargetData::rp, rt, QRhiRenderTarget::setRenderPassDescriptor(), surfacePixelSize(), and window.

Here is the call graph for this function:

◆ currentFrameCommandBuffer()

QRhiCommandBuffer * QNullSwapChain::currentFrameCommandBuffer ( )

overridevirtual

Returns: a command buffer on which rendering commands and resource updates can be recorded within a \l{QRhi::beginFrame()}{beginFrame} - \l{QRhi::endFrame()}{endFrame} block, assuming beginFrame() was called with this swapchain.

Note: The returned object is valid also after endFrame(), up until the next beginFrame(), but the returned command buffer should not be used to record any commands then. Rather, it can be used to query data collected during the frame (or previous frames), for example by calling \l{QRhiCommandBuffer::lastCompletedGpuTime()}{lastCompletedGpuTime()}.; The value must not be cached and reused between frames. The caller should not hold on to the returned object once \l{QRhi::beginFrame()}{beginFrame()} is called again. Instead, the command buffer object should be queried again by calling this function.

Implements QRhiSwapChain.

Definition at line 994 of file qrhinull.cpp.

References cb.

◆ currentFrameRenderTarget()

QRhiRenderTarget * QNullSwapChain::currentFrameRenderTarget ( )

overridevirtual

Returns: a render target that can used with beginPass() in order to render the swapchain's current backbuffer. Only valid within a QRhi::beginFrame() - QRhi::endFrame() block where beginFrame() was called with this swapchain.

Note: the value must not be cached and reused between frames

Implements QRhiSwapChain.

Definition at line 999 of file qrhinull.cpp.

References rt.

◆ destroy()

void QNullSwapChain::destroy ( )

overridevirtual

Releases (or requests deferred releasing of) the underlying native graphics resources.

Safe to call multiple times, subsequent invocations will be a no-op then.

Once destroy() is called, the QRhiResource instance can be reused, by calling create() again. That will then result in creating new native graphics resources underneath.

Note: Resources referenced by commands for the current frame should not be released until the frame is submitted by QRhi::endFrame().

The QRhiResource destructor also performs the same task, so calling this function is not necessary before deleting a QRhiResource.

See also: deleteLater()

Implements QRhiResource.

Definition at line 987 of file qrhinull.cpp.

References QRHI_RES_RHI.

Referenced by ~QNullSwapChain(), and createOrResize().

Here is the caller graph for this function:

◆ isFormatSupported()

bool QNullSwapChain::isFormatSupported ( Format f )

overridevirtual

Returns: true if the given swapchain format f is supported. SDR is always supported.

Note: Can be called independently of createOrResize(), but window() must already be set. Calling without the window set may lead to unexpected results depending on the backend and platform (most likely false for any HDR format), because HDR format support is usually tied to the output (screen) to which the swapchain's associated window belongs at any given time. If the result is true for a HDR format, then creating the swapchain with that format is expected to succeed as long as the window is not moved to another screen in the meantime.

The main use of this function is to call it before the first createOrResize() after the window is already set. This allow the QRhi backends to perform platform or windowing system specific queries to determine if the window (and the screen it is on) is capable of true HDR output with the specified format.

When the format is reported as supported, call setFormat() to set the requested format and call createOrResize(). Be aware of the consequences however: successfully requesting a HDR format will involve having to deal with a different color space, possibly doing white level correction for non-HDR-aware content, adjusting tonemapping methods, adjusting offscreen render target settings, etc.

See also: setFormat()

Implements QRhiSwapChain.

Definition at line 1009 of file qrhinull.cpp.

References QRhiSwapChain::SDR.

◆ newCompatibleRenderPassDescriptor()

QRhiRenderPassDescriptor * QNullSwapChain::newCompatibleRenderPassDescriptor ( )

overridevirtual

Returns: a new QRhiRenderPassDescriptor that is compatible with this swapchain.

The returned value is used in two ways: it can be passed to setRenderPassDescriptor() and QRhiGraphicsPipeline::setRenderPassDescriptor(). A render pass descriptor describes the attachments (color, depth/stencil) and the load/store behavior that can be affected by flags(). A QRhiGraphicsPipeline can only be used in combination with a swapchain that has a \l{QRhiRenderPassDescriptor::isCompatible()}{compatible} QRhiRenderPassDescriptor set.

See also: createOrResize()

Implements QRhiSwapChain.

Definition at line 1014 of file qrhinull.cpp.

References QRhiResource::m_rhi, and QRHI_RES_RHI.

◆ surfacePixelSize()

QSize QNullSwapChain::surfacePixelSize ( )

overridevirtual

Returns: The size of the window's associated surface or layer.

Warning: Do not assume this is the same as {QWindow::size() * QWindow::devicePixelRatio()}. With some graphics APIs and windowing system interfaces (for example, Vulkan) there is a theoretical possibility for a surface to assume a size different from the associated window. To support these cases, {rendering logic must always base size-derived calculations (such as, viewports) on the size reported from QRhiSwapChain, and never on the size queried from QWindow}.

Note: {Can also be called before createOrResize(), if at least window() is already set. This in combination with currentPixelSize() allows to detect when a swapchain needs to be resized.} However, watch out for the fact that the size of the underlying native object (surface, layer, or similar) is "live", so whenever this function is called, it returns the latest value reported by the underlying implementation, without any atomicity guarantee. Therefore, using this function to determine pixel sizes for graphics resources that are used in a frame is strongly discouraged. Rely on currentPixelSize() instead which returns a size that is atomic and will not change between createOrResize() invocations.; For depth-stencil buffers used in combination with the swapchain's color buffers, it is strongly recommended to rely on the automatic sizing and rebuilding behavior provided by the QRhiRenderBuffer:UsedWithSwapChainOnly flag. Avoid querying the surface size via this function just to get a size that can be passed to QRhiRenderBuffer::setPixelSize() as that would suffer from the lack of atomicity as described above.