GrContext Class Reference

Inheritance diagram for GrContext:

Classes
struct	CleanUpData

Public Types
enum	FlushBits { kDiscard_FlushBit = 0x2 }
	Flags that affect flush() behavior. More...
enum	PixelOpsFlags { kDontFlush_PixelOpsFlag = 0x1, kFlushWrites_PixelOp = 0x2, kUnpremul_PixelOpsFlag = 0x4 }
	These flags can be used with the read/write pixels functions below. More...
typedef void(*	PFCleanUpFunc )(const GrContext *context, void *info)
	Callback function to allow classes to cleanup on GrContext destruction. More...

Public Member Functions
GrContextThreadSafeProxy *	threadSafeProxy ()
void	resetContext (uint32_t state=kAll_GrBackendState)
	The GrContext normally assumes that no outsider is setting state within the underlying 3D API's context/device/whatever. More...
void	addCleanUp (PFCleanUpFunc cleanUp, void *info)
	Add a function to be called from within GrContext's destructor. More...
void	abandonContext ()
	Abandons all GPU resources and assumes the underlying backend 3D API context is not longer usable. More...
void	releaseResourcesAndAbandonContext ()
	This is similar to abandonContext() however the underlying 3D context is not yet lost and the GrContext will cleanup all allocated resources before returning. More...
void	getResourceCacheLimits (int *maxResources, size_t *maxResourceBytes) const
	Return the current GPU resource cache limits. More...
void	getResourceCacheUsage (int *resourceCount, size_t *resourceBytes) const
	Gets the current GPU resource cache usage. More...
void	setResourceCacheLimits (int maxResources, size_t maxResourceBytes)
	Specify the GPU resource cache limits. More...
GrTextureProvider *	textureProvider ()
const GrTextureProvider *	textureProvider () const
void	freeGpuResources ()
	Frees GPU created by the context. More...
void	purgeAllUnlockedResources ()
	Purge all the unlocked resources from the cache. More...
const GrCaps *	caps () const
	Access the context capabilities.
int	getRecommendedSampleCount (GrPixelConfig config, SkScalar dpi) const
	Returns the recommended sample count for a render target when using this context. More...
sk_sp< GrDrawContext >	makeDrawContext (SkBackingFit fit, int width, int height, GrPixelConfig config, sk_sp< SkColorSpace > colorSpace, int sampleCnt=0, GrSurfaceOrigin origin=kDefault_GrSurfaceOrigin, const SkSurfaceProps *surfaceProps=nullptr, SkBudgeted=SkBudgeted::kYes)
	Create both a GrRenderTarget and a matching GrDrawContext to wrap it. More...
void	flush (int flagsBitfield=0)
	Call to ensure all drawing to the context has been issued to the underlying 3D API. More...
void	flushIfNecessary ()
bool	readSurfacePixels (GrSurface *surface, int left, int top, int width, int height, GrPixelConfig config, void *buffer, size_t rowBytes=0, uint32_t pixelOpsFlags=0)
	Reads a rectangle of pixels from a surface. More...
bool	writeSurfacePixels (GrSurface *surface, int left, int top, int width, int height, GrPixelConfig config, const void *buffer, size_t rowBytes, uint32_t pixelOpsFlags=0)
	Writes a rectangle of pixels to a surface. More...
bool	copySurface (GrSurface *dst, GrSurface *src, const SkIRect &srcRect, const SkIPoint &dstPoint)
	Copies a rectangle of texels from src to dst. More...
bool	copySurface (GrSurface *dst, GrSurface *src)
	Helper that copies the whole surface but fails when the two surfaces are not identically sized. More...
void	flushSurfaceWrites (GrSurface *surface)
	After this returns any pending writes to the surface will have been issued to the backend 3D API.
void	flushSurfaceIO (GrSurface *surface)
	After this returns any pending reads or writes to the surface will have been issued to the backend 3D API.
void	prepareSurfaceForExternalIO (GrSurface *)
	Finalizes all pending reads and writes to the surface and also performs an MSAA resolve if necessary. More...
uint32_t	uniqueID ()
	An ID associated with this context, guaranteed to be unique.
GrGpu *	getGpu ()
const GrGpu *	getGpu () const
GrBatchFontCache *	getBatchFontCache ()
GrTextBlobCache *	getTextBlobCache ()
bool	abandoned () const
GrResourceProvider *	resourceProvider ()
const GrResourceProvider *	resourceProvider () const
GrResourceCache *	getResourceCache ()
void	getTestTarget (GrTestTarget *, sk_sp< GrDrawContext >)
void	resetGpuStats () const
	Reset GPU stats.
void	dumpCacheStats (SkString *) const
	Prints cache stats to the string if GR_CACHE_STATS == 1. More...
void	dumpCacheStatsKeyValuePairs (SkTArray< SkString > *keys, SkTArray< double > *values) const
void	printCacheStats () const
void	dumpGpuStats (SkString *) const
	Prints GPU stats to the string if GR_GPU_STATS == 1. More...
void	dumpGpuStatsKeyValuePairs (SkTArray< SkString > *keys, SkTArray< double > *values) const
void	printGpuStats () const
void	setTextBlobCacheLimit_ForTesting (size_t bytes)
	Specify the TextBlob cache limit. More...
void	setTextContextAtlasSizes_ForTesting (const GrBatchAtlasConfig *configs)
	Specify the sizes of the GrAtlasTextContext atlases. More...
void	dumpMemoryStatistics (SkTraceMemoryDump *traceMemoryDump) const
	Enumerates all cached GPU resources and dumps their memory to traceMemoryDump. More...
GrTexture *	getFontAtlasTexture (GrMaskFormat format)
	Get pointer to atlas texture for given mask format.
GrAuditTrail *	getAuditTrail ()
	SkDEBUGCODE (GrSingleOwner *debugSingleOwner() const {return &fSingleOwner;}) GrContextPriv contextPriv()
	This is only useful for debug purposes.
const GrContextPriv	contextPriv () const
Public Member Functions inherited from SkRefCntBase
	SkRefCntBase ()
	Default construct, initializing the reference count to 1.
virtual	~SkRefCntBase ()
	Destruct, asserting that the reference count is 1.
int32_t	getRefCnt () const
	Return the reference count. More...
void	validate () const
bool	unique () const
	May return true if the caller is the only owner. More...
void	ref () const
	Increment the reference count. More...
void	unref () const
	Decrement the reference count. More...

Static Public Member Functions
static GrContext *	Create (GrBackend, GrBackendContext, const GrContextOptions &options)
	Creates a GrContext for a backend context.
static GrContext *	Create (GrBackend, GrBackendContext)
static GrContext *	CreateMockContext ()
	Only defined in test apps.

Private Types
typedef SkRefCnt	INHERITED

Private Member Functions
GrDrawingManager *	drawingManager ()
bool	init (GrBackend, GrBackendContext, const GrContextOptions &options)
void	initMockContext ()
void	initCommon (const GrContextOptions &)
sk_sp< GrFragmentProcessor >	createPMToUPMEffect (GrTexture *, const GrSwizzle &, const SkMatrix &) const
	These functions create premul <-> unpremul effects if it is possible to generate a pair of effects that make a readToUPM->writeToPM->readToUPM cycle invariant. More...
sk_sp< GrFragmentProcessor >	createUPMToPMEffect (GrTexture *, const GrSwizzle &, const SkMatrix &) const
void	testPMConversionsIfNecessary (uint32_t flags)
	Called before either of the above two functions to determine the appropriate fragment processors for conversions. More...
bool	didFailPMUPMConversionTest () const
	Returns true if we've already determined that createPMtoUPMEffect and createUPMToPMEffect will fail. More...

Static Private Member Functions
static void	OverBudgetCB (void *data)
	This callback allows the resource cache to callback into the GrContext when the cache is still over budget after a purge.
static void	TextBlobCacheOverBudgetCB (void *data)
	A callback similar to the above for use by the TextBlobCache TODO move textblob draw calls below context so we can use the call above.

Private Attributes
GrGpu *	fGpu
const GrCaps *	fCaps
GrResourceCache *	fResourceCache
union {
GrResourceProvider *   fResourceProvider
GrTextureProvider *   fTextureProvider
};
SkAutoTUnref < GrContextThreadSafeProxy >	fThreadSafeProxy
GrBatchFontCache *	fBatchFontCache
SkAutoTDelete< GrTextBlobCache >	fTextBlobCache
bool	fFlushToReduceCacheSize
bool	fDidTestPMConversions
int	fPMToUPMConversion
int	fUPMToPMConversion
SkMutex	fReadPixelsMutex
SkMutex	fTestPMConversionsMutex
GrSingleOwner	fSingleOwner
SkTDArray< CleanUpData >	fCleanUpData
const uint32_t	fUniqueID
SkAutoTDelete< GrDrawingManager >	fDrawingManager
GrAuditTrail	fAuditTrail

Friends
class	GrClipStackClip
class	GrDrawingManager
class	GrContextPriv

Additional Inherited Members
Protected Member Functions inherited from SkRefCntBase
void	internal_dispose_restore_refcnt_to_1 () const
	Allow subclasses to call this if they've overridden internal_dispose so they can reset fRefCnt before the destructor is called or if they choose not to call the destructor (e.g. More...

Member Typedef Documentation

typedef void(* GrContext::PFCleanUpFunc)(const GrContext *context, void *info)

Callback function to allow classes to cleanup on GrContext destruction.

The 'info' field is filled in with the 'info' passed to addCleanUp.

Member Enumeration Documentation

enum GrContext::FlushBits

Flags that affect flush() behavior.

Enumerator
kDiscard_FlushBit	A client may reach a point where it has partially rendered a frame through a GrContext that it knows the user will never see. This flag causes the flush to skip submission of deferred content to the 3D API during the flush.

enum GrContext::PixelOpsFlags

These flags can be used with the read/write pixels functions below.

Enumerator
kDontFlush_PixelOpsFlag	The GrContext will not be flushed before the surface read or write. This means that the read or write may occur before previous draws have executed.
kFlushWrites_PixelOp	Any surface writes should be flushed to the backend 3D API after the surface operation is complete.
kUnpremul_PixelOpsFlag	The src for write or dst read is unpremultiplied. This is only respected if both the config src and dst configs are an RGBA/BGRA 8888 format.

Member Function Documentation

void GrContext::abandonContext

(

)

Abandons all GPU resources and assumes the underlying backend 3D API context is not longer usable.

Call this if you have lost the associated GPU context, and thus internal texture, buffer, etc. references/IDs are now invalid. Calling this ensures that the destructors of the GrContext and any of its created resource objects will not make backend 3D API calls. Content rendered but not previously flushed may be lost. After this function is called all subsequent calls on the GrContext will fail or be no-ops.

The typical use case for this function is that the underlying 3D context was lost and further API calls may crash.

void GrContext::addCleanUp ( PFCleanUpFunc  cleanUp, void *  info  )

inline

Add a function to be called from within GrContext's destructor.

This gives classes a chance to free resources held on a per context basis. The 'info' parameter will be stored and passed to the callback function.

bool GrContext::copySurface	(	GrSurface *	dst,
		GrSurface *	src,
		const SkIRect &	srcRect,
		const SkIPoint &	dstPoint
	)

Copies a rectangle of texels from src to dst.

Parameters

dst	the surface to copy to.
src	the surface to copy from.
srcRect	the rectangle of the src that should be copied.
dstPoint	the translation applied when writing the srcRect's pixels to the dst.

bool GrContext::copySurface ( GrSurface *  dst, GrSurface *  src  )

inline

Helper that copies the whole surface but fails when the two surfaces are not identically sized.

sk_sp<GrFragmentProcessor> GrContext::createPMToUPMEffect ( GrTexture *  , const GrSwizzle &  , const SkMatrix &    ) const

private

These functions create premul <-> unpremul effects if it is possible to generate a pair of effects that make a readToUPM->writeToPM->readToUPM cycle invariant.

Otherwise, they return NULL. They also can perform a swizzle as part of the draw.

bool GrContext::didFailPMUPMConversionTest ( ) const

private

Returns true if we've already determined that createPMtoUPMEffect and createUPMToPMEffect will fail.

In such cases fall back to SW conversion.

void GrContext::dumpCacheStats

(

SkString *

)

const

Prints cache stats to the string if GR_CACHE_STATS == 1.

void GrContext::dumpGpuStats

(

SkString *

)

const

Prints GPU stats to the string if GR_GPU_STATS == 1.

void GrContext::dumpMemoryStatistics

(

SkTraceMemoryDump *

traceMemoryDump

)

const

Enumerates all cached GPU resources and dumps their memory to traceMemoryDump.

void GrContext::flush

(

int

flagsBitfield = 0

)

Call to ensure all drawing to the context has been issued to the underlying 3D API.

Parameters

flagsBitfield

flags that control the flushing behavior. See FlushBits.

void GrContext::freeGpuResources

(

)

Frees GPU created by the context.

Can be called to reduce GPU memory pressure.

int GrContext::getRecommendedSampleCount	(	GrPixelConfig	config,
		SkScalar	dpi
	)		const

Returns the recommended sample count for a render target when using this context.

Parameters

config	the configuration of the render target.
dpi	the display density in dots per inch.

Returns

sample count that should be perform well and have good enough rendering quality for the display. Alternatively returns 0 if MSAA is not supported or recommended to be used by default.

void GrContext::getResourceCacheLimits	(	int *	maxResources,
		size_t *	maxResourceBytes
	)		const

Return the current GPU resource cache limits.

Parameters

maxResources	If non-null, returns maximum number of resources that can be held in the cache.
maxResourceBytes	If non-null, returns maximum number of bytes of video memory that can be held in the cache.

void GrContext::getResourceCacheUsage	(	int *	resourceCount,
		size_t *	resourceBytes
	)		const

Gets the current GPU resource cache usage.

Parameters

resourceCount	If non-null, returns the number of resources that are held in the cache.
maxResourceBytes	If non-null, returns the total number of bytes of video memory held in the cache.

sk_sp<GrDrawContext> GrContext::makeDrawContext	(	SkBackingFit	fit,
		int	width,
		int	height,
		GrPixelConfig	config,
		sk_sp< SkColorSpace >	colorSpace,
		int	sampleCnt = 0,
		GrSurfaceOrigin	origin = kDefault_GrSurfaceOrigin,
		const SkSurfaceProps *	surfaceProps = nullptr,
		SkBudgeted	= SkBudgeted::kYes
	)

Create both a GrRenderTarget and a matching GrDrawContext to wrap it.

We guarantee that "asTexture" will succeed for drawContexts created via this entry point.

void GrContext::prepareSurfaceForExternalIO

(

GrSurface *

)

Finalizes all pending reads and writes to the surface and also performs an MSAA resolve if necessary.

It is not necessary to call this before reading the render target via Skia/GrContext. GrContext will detect when it must perform a resolve before reading pixels back from the surface or using it as a texture.

void GrContext::purgeAllUnlockedResources

(

)

Purge all the unlocked resources from the cache.

This entry point is mainly meant for timing texture uploads and is not defined in normal builds of Skia.

bool GrContext::readSurfacePixels	(	GrSurface *	surface,
		int	left,
		int	top,
		int	width,
		int	height,
		GrPixelConfig	config,
		void *	buffer,
		size_t	rowBytes = 0,
		uint32_t	pixelOpsFlags = 0
	)

Reads a rectangle of pixels from a surface.

Parameters

surface	the surface to read from.
left	left edge of the rectangle to read (inclusive)
top	top edge of the rectangle to read (inclusive)
width	width of rectangle to read in pixels.
height	height of rectangle to read in pixels.
config	the pixel config of the destination buffer
buffer	memory to read the rectangle into.
rowBytes	number of bytes bewtween consecutive rows. Zero means rows are tightly packed.
pixelOpsFlags	see PixelOpsFlags enum above.

Returns

true if the read succeeded, false if not. The read can fail because of an unsupported pixel configs

void GrContext::releaseResourcesAndAbandonContext

(

)

This is similar to abandonContext() however the underlying 3D context is not yet lost and the GrContext will cleanup all allocated resources before returning.

After returning it will assume that the underlying context may no longer be valid.

The typical use case for this function is that the client is going to destroy the 3D context but can't guarantee that GrContext will be destroyed first (perhaps because it may be ref'ed elsewhere by either the client or Skia objects).

void GrContext::resetContext

(

uint32_t

state = kAll_GrBackendState

)

The GrContext normally assumes that no outsider is setting state within the underlying 3D API's context/device/whatever.

This call informs the context that the state was modified and it should resend. Shouldn't be called frequently for good performance. The flag bits, state, is dpendent on which backend is used by the context, either GL or D3D (possible in future).

void GrContext::setResourceCacheLimits	(	int	maxResources,
		size_t	maxResourceBytes
	)

Specify the GPU resource cache limits.

If the current cache exceeds either of these, it will be purged (LRU) to keep the cache within these limits.

Parameters

maxResources	The maximum number of resources that can be held in the cache.
maxResourceBytes	The maximum number of bytes of video memory that can be held in the cache.

void GrContext::setTextBlobCacheLimit_ForTesting

(

size_t

bytes

)

Specify the TextBlob cache limit.

If the current cache exceeds this limit it will purge. this is for testing only

void GrContext::setTextContextAtlasSizes_ForTesting

(

const GrBatchAtlasConfig *

configs

)

Specify the sizes of the GrAtlasTextContext atlases.

The configs pointer below should be to an array of 3 entries

void GrContext::testPMConversionsIfNecessary ( uint32_t  flags )

private

Called before either of the above two functions to determine the appropriate fragment processors for conversions.

This must be called by readSurfacePixels before a mutex is taken, since testingvPM conversions itself will call readSurfacePixels

bool GrContext::writeSurfacePixels	(	GrSurface *	surface,
		int	left,
		int	top,
		int	width,
		int	height,
		GrPixelConfig	config,
		const void *	buffer,
		size_t	rowBytes,
		uint32_t	pixelOpsFlags = 0
	)

Writes a rectangle of pixels to a surface.

Parameters

surface	the surface to write to.
left	left edge of the rectangle to write (inclusive)
top	top edge of the rectangle to write (inclusive)
width	width of rectangle to write in pixels.
height	height of rectangle to write in pixels.
config	the pixel config of the source buffer
buffer	memory to read pixels from
rowBytes	number of bytes between consecutive rows. Zero means rows are tightly packed.
pixelOpsFlags	see PixelOpsFlags enum above.

Returns

true if the write succeeded, false if not. The write can fail because of an unsupported combination of surface and src configs.

---

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

• include/gpu/GrContext.h