flutter::ImageExternalTextureGL Class Reference

#include <image_external_texture_gl.h>

Inheritance diagram for flutter::ImageExternalTextureGL:

Classes
struct	GlEntry

Public Member Functions
	ImageExternalTextureGL (int64_t id, const fml::jni::ScopedJavaGlobalRef< jobject > &image_textury_entry, const std::shared_ptr< PlatformViewAndroidJNI > &jni_facade, ImageExternalTexture::ImageLifecycle lifecycle)
Public Member Functions inherited from flutter::ImageExternalTexture
	ImageExternalTexture (int64_t id, const fml::jni::ScopedJavaGlobalRef< jobject > &image_texture_entry, const std::shared_ptr< PlatformViewAndroidJNI > &jni_facade, ImageLifecycle lifecycle)
virtual	~ImageExternalTexture ()
Public Member Functions inherited from flutter::Texture
	Texture (int64_t id)
virtual	~Texture ()
int64_t	Id ()
Public Member Functions inherited from flutter::ContextListener
	ContextListener ()
	~ContextListener ()

Protected Member Functions
void	Attach (PaintContext &context) override
void	Detach () override
void	ProcessFrame (PaintContext &context, const SkRect &bounds) override
	Subclasses override this method to bind the latest representation of the hardware buffer wrapped by this texture instance to their own graphics package specific texture classes (SkImage, impeller::Texture, etc...).
virtual sk_sp< flutter::DlImage >	CreateDlImage (PaintContext &context, const SkRect &bounds, std::optional< HardwareBufferKey > id, impeller::UniqueEGLImageKHR &&egl_image)=0
void	UpdateImage (JavaLocalRef &hardware_buffer, const SkRect &bounds, PaintContext &context)
impeller::UniqueEGLImageKHR	CreateEGLImage (AHardwareBuffer *buffer)
	FML_DISALLOW_COPY_AND_ASSIGN (ImageExternalTextureGL)
Protected Member Functions inherited from flutter::ImageExternalTexture
JavaLocalRef	AcquireLatestImage ()
void	CloseImage (const fml::jni::JavaRef< jobject > &image)
JavaLocalRef	HardwareBufferFor (const fml::jni::JavaRef< jobject > &image)
void	CloseHardwareBuffer (const fml::jni::JavaRef< jobject > &hardware_buffer)
AHardwareBuffer *	AHardwareBufferFor (const fml::jni::JavaRef< jobject > &hardware_buffer)

Protected Attributes
std::unordered_map< HardwareBufferKey, GlEntry >	gl_entries_
Protected Attributes inherited from flutter::ImageExternalTexture
fml::jni::ScopedJavaGlobalRef< jobject >	image_texture_entry_
std::shared_ptr< PlatformViewAndroidJNI >	jni_facade_
AttachmentState	state_ = AttachmentState::kUninitialized
sk_sp< flutter::DlImage >	dl_image_
ImageLRU	image_lru_ = ImageLRU()

Additional Inherited Members
Public Types inherited from flutter::ImageExternalTexture
enum class	ImageLifecycle {   kReset ,   kKeepAlive }
	Whether the last image should be reset when the context is destroyed. More...
Protected Types inherited from flutter::ImageExternalTexture
enum class	AttachmentState {   kUninitialized ,   kAttached ,   kDetached }

Detailed Description

Definition at line 18 of file image_external_texture_gl.h.

Constructor & Destructor Documentation

ImageExternalTextureGL()

flutter::ImageExternalTextureGL::ImageExternalTextureGL	(	int64_t	id,
		const fml::jni::ScopedJavaGlobalRef< jobject > &	image_textury_entry,
		const std::shared_ptr< PlatformViewAndroidJNI > &	jni_facade,
		ImageExternalTexture::ImageLifecycle	lifecycle
	)

Definition at line 24 of file image_external_texture_gl.cc.

    : ImageExternalTexture(id, image_texture_entry, jni_facade, lifecycle) {}

Member Function Documentation

Attach()

void flutter::ImageExternalTextureGL::Attach ( PaintContext &  context )

overrideprotectedvirtual

Implements flutter::ImageExternalTexture.

Definition at line 31 of file image_external_texture_gl.cc.

                                                         {
  if (state_ == AttachmentState::kUninitialized) {
    // TODO(johnmccurtchan): We currently display the first frame after an
    // attach-detach cycle as blank. There seems to be an issue on some
    // devices where ImageReaders/Images from before the detach aren't
    // valid after the attach. According to Android folks this doesn't
    // match the spec. Revisit this in the future.
    // See https://github.com/flutter/flutter/issues/142978 and
    // https://github.com/flutter/flutter/issues/139039.
    state_ = AttachmentState::kAttached;
  }
}

References flutter::ImageExternalTexture::kAttached, flutter::ImageExternalTexture::kUninitialized, and flutter::ImageExternalTexture::state_.

CreateDlImage()

virtual sk_sp< flutter::DlImage > flutter::ImageExternalTextureGL::CreateDlImage ( PaintContext &  context, const SkRect &  bounds, std::optional< HardwareBufferKey >  id, impeller::UniqueEGLImageKHR &&  egl_image  )

protectedpure virtual

Referenced by UpdateImage().

CreateEGLImage()

impeller::UniqueEGLImageKHR flutter::ImageExternalTextureGL::CreateEGLImage ( AHardwareBuffer *  buffer )

protected

Definition at line 84 of file image_external_texture_gl.cc.

                                      {
  if (hardware_buffer == nullptr) {
    return impeller::UniqueEGLImageKHR();
  }
 
  EGLDisplay display = eglGetCurrentDisplay();
  if (display == EGL_NO_DISPLAY) {
    // This could happen when running in a deferred task that executes after
    // the thread has lost its EGL state.
    return impeller::UniqueEGLImageKHR();
  }
 
  EGLClientBuffer client_buffer =
      impeller::android::GetProcTable().eglGetNativeClientBufferANDROID(
          hardware_buffer);
  FML_DCHECK(client_buffer != nullptr);
  if (client_buffer == nullptr) {
    FML_LOG(ERROR) << "eglGetNativeClientBufferAndroid returned null.";
    return impeller::UniqueEGLImageKHR();
  }
 
  impeller::EGLImageKHRWithDisplay maybe_image =
      impeller::EGLImageKHRWithDisplay{
          eglCreateImageKHR(display, EGL_NO_CONTEXT, EGL_NATIVE_BUFFER_ANDROID,
                            client_buffer, 0),
          display};
 
  return impeller::UniqueEGLImageKHR(maybe_image);
}

References FML_DCHECK, FML_LOG, and impeller::android::GetProcTable().

Referenced by UpdateImage().

Detach()

void flutter::ImageExternalTextureGL::Detach ( )

overrideprotectedvirtual

Implements flutter::ImageExternalTexture.

Definition at line 79 of file image_external_texture_gl.cc.

                                    {
  image_lru_.Clear();
  gl_entries_.clear();
}

References flutter::ImageLRU::Clear(), gl_entries_, and flutter::ImageExternalTexture::image_lru_.

FML_DISALLOW_COPY_AND_ASSIGN()

flutter::ImageExternalTextureGL::FML_DISALLOW_COPY_AND_ASSIGN ( ImageExternalTextureGL  )

protected

ProcessFrame()

void flutter::ImageExternalTextureGL::ProcessFrame ( PaintContext &  context, const SkRect &  bounds  )

overrideprotectedvirtual

Subclasses override this method to bind the latest representation of the hardware buffer wrapped by this texture instance to their own graphics package specific texture classes (SkImage, impeller::Texture, etc...).

After a call to this method, attachment state of this instance must be kAttached. That is the responsibility of the subclass.

Parameters

	context	The context
[in]	bounds	The bounds

Implements flutter::ImageExternalTexture.

Definition at line 68 of file image_external_texture_gl.cc.

                                                                {
  JavaLocalRef image = AcquireLatestImage();
  if (image.is_null()) {
    return;
  }
  JavaLocalRef hardware_buffer = HardwareBufferFor(image);
  UpdateImage(hardware_buffer, bounds, context);
  CloseHardwareBuffer(hardware_buffer);
}

References flutter::ImageExternalTexture::AcquireLatestImage(), flutter::ImageExternalTexture::CloseHardwareBuffer(), flutter::ImageExternalTexture::HardwareBufferFor(), image, and UpdateImage().

UpdateImage()

void flutter::ImageExternalTextureGL::UpdateImage ( JavaLocalRef &  hardware_buffer, const SkRect &  bounds, PaintContext &  context  )

protected

Definition at line 44 of file image_external_texture_gl.cc.

                                                                {
  AHardwareBuffer* latest_hardware_buffer = AHardwareBufferFor(hardware_buffer);
  std::optional<HardwareBufferKey> key =
      impeller::android::HardwareBuffer::GetSystemUniqueID(
          latest_hardware_buffer);
  auto existing_image = image_lru_.FindImage(key);
  if (existing_image != nullptr) {
    dl_image_ = existing_image;
    return;
  }
 
  auto egl_image = CreateEGLImage(latest_hardware_buffer);
  if (!egl_image.is_valid()) {
    return;
  }
 
  dl_image_ = CreateDlImage(context, bounds, key, std::move(egl_image));
  if (key.has_value()) {
    gl_entries_.erase(image_lru_.AddImage(dl_image_, key.value()));
  }
}

References flutter::ImageLRU::AddImage(), flutter::ImageExternalTexture::AHardwareBufferFor(), CreateDlImage(), CreateEGLImage(), flutter::ImageExternalTexture::dl_image_, flutter::ImageLRU::FindImage(), impeller::android::HardwareBuffer::GetSystemUniqueID(), gl_entries_, flutter::ImageExternalTexture::image_lru_, and key.

Referenced by ProcessFrame().

Member Data Documentation

gl_entries_

std::unordered_map<HardwareBufferKey, GlEntry> flutter::ImageExternalTextureGL::gl_entries_

protected

Definition at line 56 of file image_external_texture_gl.h.

Referenced by Detach(), and UpdateImage().

---

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

• shell/platform/android/image_external_texture_gl.h
• shell/platform/android/image_external_texture_gl.cc