flutter::DlImage Class Reference

Represents an image whose allocation is (usually) resident on device memory. More...

#include <dl_image.h>

Inheritance diagram for flutter::DlImage:

Public Types
enum class	OwningContext {   kRaster ,   kIO }
enum class	Type {   kSkia ,   kImpeller }
	The backend type of this image. More...

Public Member Functions
virtual	~DlImage ()
virtual Type	GetImageType () const =0
	Returns the backend type of this image.
virtual const DlImageSkia *	asSkiaImage () const
	Safe downcast to DlImageSkia.
virtual const impeller::DlImageImpeller *	asImpellerImage () const
	Safe downcast to DlImageImpeller.
virtual bool	isTextureBacked () const =0
	Returns true if the image is backed by a GPU texture.
virtual DlColorSpace	GetColorSpace () const =0
	Gets the color space of the image.
virtual bool	isOpaque () const =0
	If the pixel format of this image ignores alpha, this returns true. This method might conservatively return false when it cannot guarnatee an opaque image, for example when the pixel format of the image supports alpha but the image is made up of entirely opaque pixels.
virtual bool	isUIThreadSafe () const =0
	If the underlying platform image held by this object has no threading requirements for the release of that image (or if arrangements have already been made to forward that image to the correct thread upon deletion), this method returns true.
virtual DlISize	GetSize () const =0
virtual size_t	GetApproximateByteSize () const =0
int	width () const
int	height () const
DlIRect	GetBounds () const
virtual OwningContext	owning_context () const
virtual std::optional< std::string >	get_error () const
bool	Equals (const DlImage *other) const
bool	Equals (const DlImage &other) const
bool	Equals (const sk_sp< const DlImage > &other) const

Protected Member Functions
	DlImage ()

Detailed Description

Represents an image whose allocation is (usually) resident on device memory.

Since it is usually impossible or expensive to transmute images for one rendering backend to another, these objects are backend specific.

Definition at line 34 of file dl_image.h.

Member Enumeration Documentation

OwningContext

enum class flutter::DlImage::OwningContext

strong

Enumerator
kRaster
kIO

Definition at line 37 of file dl_image.h.

{ kRaster, kIO };

Type

enum class flutter::DlImage::Type

strong

The backend type of this image.

Enumerator
kSkia
kImpeller

Definition at line 44 of file dl_image.h.

{ kSkia, kImpeller };

Constructor & Destructor Documentation

~DlImage()

flutter::DlImage::~DlImage ( )

virtualdefault

DlImage()

flutter::DlImage::DlImage ( )

protecteddefault

Member Function Documentation

asImpellerImage()

virtual const impeller::DlImageImpeller * flutter::DlImage::asImpellerImage ( ) const

inlinevirtual

Safe downcast to DlImageImpeller.

Returns

A pointer to DlImageImpeller or null if not an Impeller image.

Reimplemented in impeller::DlImageImpeller.

Definition at line 65 of file dl_image.h.

                                                                 {
    return nullptr;
  }

asSkiaImage()

virtual const DlImageSkia * flutter::DlImage::asSkiaImage ( ) const

inlinevirtual

Safe downcast to DlImageSkia.

Returns

A pointer to DlImageSkia or null if not a Skia image.

Reimplemented in flutter::DlImageSkia.

Definition at line 58 of file dl_image.h.

{ return nullptr; }

Referenced by Equals().

Equals() [1/3]

bool flutter::DlImage::Equals ( const DlImage &  other ) const

inline

Definition at line 145 of file dl_image.h.

{ return Equals(&other); }

References Equals().

Referenced by Equals().

Equals() [2/3]

bool flutter::DlImage::Equals

(

const DlImage *

other

)

const

Definition at line 31 of file dl_image.cc.

                                               {
  if (!other) {
    return false;
  }
  if (this == other) {
    return true;
  }
 
  auto skia_this = asSkiaImage();
  auto skia_other = other->asSkiaImage();
  if (!skia_this || !skia_other) {
    // Impeller images have pointer equality (handled by this == other)
    return false;
  }
  return skia_this->skia_image() == skia_other->skia_image();
}

References asSkiaImage(), and flutter::DlImageSkia::skia_image().

Referenced by Equals().

Equals() [3/3]

bool flutter::DlImage::Equals ( const sk_sp< const DlImage > &  other ) const

inline

Definition at line 147 of file dl_image.h.

                                                       {
    return Equals(other.get());
  }

References Equals().

get_error()

std::optional< std::string > flutter::DlImage::get_error ( ) const

virtual

Returns

An error, if any, that occurred when trying to create the image.

Reimplemented in flutter::DlDeferredImageGPUSkia, and flutter::PixelDeferredImageGPUImpeller.

Definition at line 27 of file dl_image.cc.

                                                {
  return std::nullopt;
}

GetApproximateByteSize()

virtual size_t flutter::DlImage::GetApproximateByteSize ( ) const

pure virtual

Returns

The approximate byte size of the allocation of this image. This takes into account details such as mip-mapping. The allocation is usually resident in device memory.

Implemented in flutter::DlImageSkia, impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, flutter::DlDeferredImageGPUSkia, flutter::DlImageGPU, flutter::PixelDeferredImageGPUImpeller, and Skwasm::DlWimpImageBase.

GetBounds()

DlIRect flutter::DlImage::GetBounds

(

)

const

Returns

The bounds of the pixel grid with 0, 0 as origin. A convenience method that calls |DlImage::dimensions|.

Definition at line 23 of file dl_image.cc.

                                 {
  return DlIRect::MakeSize(GetSize());
}

References GetSize(), and impeller::TRect< T >::MakeSize().

GetColorSpace()

virtual DlColorSpace flutter::DlImage::GetColorSpace ( ) const

pure virtual

Gets the color space of the image.

Returns

The color space.

Implemented in flutter::DlImageSkia, impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, flutter::PixelDeferredImageGPUImpeller, and Skwasm::DlWimpImageBase.

GetImageType()

virtual Type flutter::DlImage::GetImageType ( ) const

pure virtual

Returns the backend type of this image.

Returns

The image type.

Implemented in flutter::DlImageSkia, and impeller::DlImageImpeller.

GetSize()

virtual DlISize flutter::DlImage::GetSize ( ) const

pure virtual

Returns

The dimensions of the pixel grid.

Implemented in flutter::DlImageSkia, impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, flutter::DlDeferredImageGPUSkia, flutter::DlImageGPU, flutter::PixelDeferredImageGPUImpeller, and Skwasm::DlWimpImageBase.

Referenced by GetBounds(), height(), and width().

height()

int flutter::DlImage::height

(

)

const

Returns

The height of the pixel grid. A convenience method that calls |DlImage::dimensions|.

Definition at line 19 of file dl_image.cc.

                          {
  return GetSize().height;
};

References GetSize(), and impeller::TSize< T >::height.

isOpaque()

virtual bool flutter::DlImage::isOpaque ( ) const

pure virtual

If the pixel format of this image ignores alpha, this returns true. This method might conservatively return false when it cannot guarnatee an opaque image, for example when the pixel format of the image supports alpha but the image is made up of entirely opaque pixels.

Returns

True if the pixel format of this image ignores alpha.

Implemented in flutter::DlImageSkia, impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, flutter::DlDeferredImageGPUSkia, flutter::DlImageGPU, flutter::PixelDeferredImageGPUImpeller, and Skwasm::DlWimpImageBase.

isTextureBacked()

virtual bool flutter::DlImage::isTextureBacked ( ) const

pure virtual

Returns true if the image is backed by a GPU texture.

Implemented in flutter::DlImageSkia, and impeller::DlImageImpeller.

isUIThreadSafe()

virtual bool flutter::DlImage::isUIThreadSafe ( ) const

pure virtual

If the underlying platform image held by this object has no threading requirements for the release of that image (or if arrangements have already been made to forward that image to the correct thread upon deletion), this method returns true.

Returns

True if the underlying image is held in a thread-safe manner.

Implemented in flutter::DlImageSkia, impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, flutter::DlDeferredImageGPUSkia, flutter::DlImageGPU, flutter::PixelDeferredImageGPUImpeller, and Skwasm::DlWimpImageBase.

owning_context()

virtual OwningContext flutter::DlImage::owning_context ( ) const

inlinevirtual

Returns

Specifies which context was used to create this image. The image must be collected on the same task runner as its context.

Reimplemented in impeller::DlImageImpellerTexture, flutter::DlDeferredImageGPUImpeller, and flutter::DlDeferredImageGPUSkia.

Definition at line 136 of file dl_image.h.

{ return OwningContext::kIO; }

References kIO.

Referenced by impeller::DlImageImpeller::Make().

width()

int flutter::DlImage::width

(

)

const

Returns

The width of the pixel grid. A convenience method that calls |DlImage::dimensions|.

Definition at line 15 of file dl_image.cc.

                         {
  return GetSize().width;
};

References GetSize(), and impeller::TSize< T >::width.

---

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

• display_list/image/dl_image.h
• display_list/image/dl_image.cc