/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <gui/BufferQueueDefs.h>
#include <gui/ConsumerBase.h>
#include <ui/FenceTime.h>
#include <ui/GraphicBuffer.h>
#include <utils/Mutex.h>
#include <utils/String8.h>
#include "EGLConsumer.h"
#include "ImageConsumer.h"
namespace android {
namespace uirenderer {
class RenderState;
}
/*
* SurfaceTexture consumes buffers of graphics data from a BufferQueue,
* and makes them available to HWUI render thread as a SkImage and to
* an application GL render thread as an OpenGL texture.
*
* When attached to an application GL render thread, a typical usage
* pattern is to set up the SurfaceTexture with the
* desired options, and call updateTexImage() when a new frame is desired.
* If a new frame is available, the texture will be updated. If not,
* the previous contents are retained.
*
* When attached to a HWUI render thread, the TextureView implementation
* calls dequeueImage, which either pulls a new SkImage or returns the
* last cached SkImage if BufferQueue is empty.
* When attached to HWUI render thread, SurfaceTexture is compatible to
* both Vulkan and GL drawing pipelines.
*/
class ANDROID_API SurfaceTexture : public ConsumerBase {
public:
enum { TEXTURE_EXTERNAL = 0x8D65 }; // GL_TEXTURE_EXTERNAL_OES
typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
/**
* SurfaceTexture constructs a new SurfaceTexture object. If the constructor with
* the tex parameter is used, tex indicates the name of the OpenGL ES
* texture to which images are to be streamed. texTarget specifies the
* OpenGL ES texture target to which the texture will be bound in
* updateTexImage. useFenceSync specifies whether fences should be used to
* synchronize access to buffers if that behavior is enabled at
* compile-time.
*
* A SurfaceTexture may be detached from one OpenGL ES context and then
* attached to a different context using the detachFromContext and
* attachToContext methods, respectively. The intention of these methods is
* purely to allow a SurfaceTexture to be transferred from one consumer
* context to another. If such a transfer is not needed there is no
* requirement that either of these methods be called.
*
* If the constructor with the tex parameter is used, the SurfaceTexture is
* created in a state where it is considered attached to an OpenGL ES
* context for the purposes of the attachToContext and detachFromContext
* methods. However, despite being considered "attached" to a context, the
* specific OpenGL ES context doesn't get latched until the first call to
* updateTexImage. After that point, all calls to updateTexImage must be
* made with the same OpenGL ES context current.
*
* If the constructor without the tex parameter is used, the SurfaceTexture is
* created in a detached state, and attachToContext must be called before
* calls to updateTexImage.
*/
SurfaceTexture(const sp<IGraphicBufferConsumer>& bq, uint32_t tex, uint32_t texureTarget,
bool useFenceSync, bool isControlledByApp);
SurfaceTexture(const sp<IGraphicBufferConsumer>& bq, uint32_t texureTarget, bool useFenceSync,
bool isControlledByApp);
/**
* updateTexImage acquires the most recently queued buffer, and sets the
* image contents of the target texture to it.
*
* This call may only be made while the OpenGL ES context to which the
* target texture belongs is bound to the calling thread.
*
* This calls doGLFenceWait to ensure proper synchronization.
*/
status_t updateTexImage();
/**
* releaseTexImage releases the texture acquired in updateTexImage().
* This is intended to be used in single buffer mode.
*
* This call may only be made while the OpenGL ES context to which the
* target texture belongs is bound to the calling thread.
*/
status_t releaseTexImage();
/**
* getTransformMatrix retrieves the 4x4 texture coordinate transform matrix
* associated with the texture image set by the most recent call to
* updateTexImage.
*
* This transform matrix maps 2D homogeneous texture coordinates of the form
* (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture
* coordinate that should be used to sample that location from the texture.
* Sampling the texture outside of the range of this transform is undefined.
*
* This transform is necessary to compensate for transforms that the stream
* content producer may implicitly apply to the content. By forcing users of
* a SurfaceTexture to apply this transform we avoid performing an extra
* copy of the data that would be needed to hide the transform from the
* user.
*
* The matrix is stored in column-major order so that it may be passed
* directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv
* functions.
*/
void getTransformMatrix(float mtx[16]);
/**
* Computes the transform matrix documented by getTransformMatrix
* from the BufferItem sub parts.
*/
static void computeTransformMatrix(float outTransform[16], const sp<GraphicBuffer>& buf,
const Rect& cropRect, uint32_t transform, bool filtering);
/**
* Scale the crop down horizontally or vertically such that it has the
* same aspect ratio as the buffer does.
*/
static Rect scaleDownCrop(const Rect& crop, uint32_t bufferWidth, uint32_t bufferHeight);
/**
* getTimestamp retrieves the timestamp associated with the texture image
* set by the most recent call to updateTexImage.
*
* The timestamp is in nanoseconds, and is monotonically increasing. Its
* other semantics (zero point, etc) are source-dependent and should be
* documented by the source.
*/
int64_t getTimestamp();
/**
* getDataSpace retrieves the DataSpace associated with the texture image
* set by the most recent call to updateTexImage.
*/
android_dataspace getCurrentDataSpace();
/**
* getFrameNumber retrieves the frame number associated with the texture
* image set by the most recent call to updateTexImage.
*
* The frame number is an incrementing counter set to 0 at the creation of
* the BufferQueue associated with this consumer.
*/
uint64_t getFrameNumber();
/**
* setDefaultBufferSize is used to set the size of buffers returned by
* requestBuffers when a with and height of zero is requested.
* A call to setDefaultBufferSize() may trigger requestBuffers() to
* be called from the client.
* The width and height parameters must be no greater than the minimum of
* GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
* An error due to invalid dimensions might not be reported until
* updateTexImage() is called.
*/
status_t setDefaultBufferSize(uint32_t width, uint32_t height);
/**
* setFilteringEnabled sets whether the transform matrix should be computed
* for use with bilinear filtering.
*/
void setFilteringEnabled(bool enabled);
/**
* getCurrentTextureTarget returns the texture target of the current
* texture as returned by updateTexImage().
*/
uint32_t getCurrentTextureTarget() const;
/**
* getCurrentCrop returns the cropping rectangle of the current buffer.
*/
Rect getCurrentCrop() const;
/**
* getCurrentTransform returns the transform of the current buffer.
*/
uint32_t getCurrentTransform() const;
/**
* getCurrentScalingMode returns the scaling mode of the current buffer.
*/
uint32_t getCurrentScalingMode() const;
/**
* getCurrentFence returns the fence indicating when the current buffer is
* ready to be read from.
*/
sp<Fence> getCurrentFence() const;
/**
* getCurrentFence returns the FenceTime indicating when the current
* buffer is ready to be read from.
*/
std::shared_ptr<FenceTime> getCurrentFenceTime() const;
/**
* setConsumerUsageBits overrides the ConsumerBase method to OR
* DEFAULT_USAGE_FLAGS to usage.
*/
status_t setConsumerUsageBits(uint64_t usage);
/**
* detachFromContext detaches the SurfaceTexture from the calling thread's
* current OpenGL ES context. This context must be the same as the context
* that was current for previous calls to updateTexImage.
*
* Detaching a SurfaceTexture from an OpenGL ES context will result in the
* deletion of the OpenGL ES texture object into which the images were being
* streamed. After a SurfaceTexture has been detached from the OpenGL ES
* context calls to updateTexImage will fail returning INVALID_OPERATION
* until the SurfaceTexture is attached to a new OpenGL ES context using the
* attachToContext method.
*/
status_t detachFromContext();
/**
* attachToContext attaches a SurfaceTexture that is currently in the
* 'detached' state to the current OpenGL ES context. A SurfaceTexture is
* in the 'detached' state iff detachFromContext has successfully been
* called and no calls to attachToContext have succeeded since the last
* detachFromContext call. Calls to attachToContext made on a
* SurfaceTexture that is not in the 'detached' state will result in an
* INVALID_OPERATION error.
*
* The tex argument specifies the OpenGL ES texture object name in the
* new context into which the image contents will be streamed. A successful
* call to attachToContext will result in this texture object being bound to
* the texture target and populated with the image contents that were
* current at the time of the last call to detachFromContext.
*/
status_t attachToContext(uint32_t tex);
sk_sp<SkImage> dequeueImage(SkMatrix& transformMatrix, bool* queueEmpty,
uirenderer::RenderState& renderState);
/**
* attachToView attaches a SurfaceTexture that is currently in the
* 'detached' state to HWUI View system.
*/
void attachToView();
/**
* detachFromView detaches a SurfaceTexture from HWUI View system.
*/
void detachFromView();
protected:
/**
* abandonLocked overrides the ConsumerBase method to clear
* mCurrentTextureImage in addition to the ConsumerBase behavior.
*/
virtual void abandonLocked();
/**
* dumpLocked overrides the ConsumerBase method to dump SurfaceTexture-
* specific info in addition to the ConsumerBase behavior.
*/
virtual void dumpLocked(String8& result, const char* prefix) const override;
/**
* acquireBufferLocked overrides the ConsumerBase method to update the
* mEglSlots array in addition to the ConsumerBase behavior.
*/
virtual status_t acquireBufferLocked(BufferItem* item, nsecs_t presentWhen,
uint64_t maxFrameNumber = 0) override;
/**
* releaseBufferLocked overrides the ConsumerBase method to update the
* mEglSlots array in addition to the ConsumerBase.
*/
virtual status_t releaseBufferLocked(int slot, const sp<GraphicBuffer> graphicBuffer,
EGLDisplay display, EGLSyncKHR eglFence) override;
/**
* freeBufferLocked frees up the given buffer slot. If the slot has been
* initialized this will release the reference to the GraphicBuffer in that
* slot and destroy the EGLImage in that slot. Otherwise it has no effect.
*
* This method must be called with mMutex locked.
*/
virtual void freeBufferLocked(int slotIndex);
/**
* computeCurrentTransformMatrixLocked computes the transform matrix for the
* current texture. It uses mCurrentTransform and the current GraphicBuffer
* to compute this matrix and stores it in mCurrentTransformMatrix.
* mCurrentTextureImage must not be NULL.
*/
void computeCurrentTransformMatrixLocked();
/**
* The default consumer usage flags that SurfaceTexture always sets on its
* BufferQueue instance; these will be OR:d with any additional flags passed
* from the SurfaceTexture user. In particular, SurfaceTexture will always
* consume buffers as hardware textures.
*/
static const uint64_t DEFAULT_USAGE_FLAGS = GraphicBuffer::USAGE_HW_TEXTURE;
/**
* mCurrentCrop is the crop rectangle that applies to the current texture.
* It gets set each time updateTexImage is called.
*/
Rect mCurrentCrop;
/**
* mCurrentTransform is the transform identifier for the current texture. It
* gets set each time updateTexImage is called.
*/
uint32_t mCurrentTransform;
/**
* mCurrentScalingMode is the scaling mode for the current texture. It gets
* set each time updateTexImage is called.
*/
uint32_t mCurrentScalingMode;
/**
* mCurrentFence is the fence received from BufferQueue in updateTexImage.
*/
sp<Fence> mCurrentFence;
/**
* The FenceTime wrapper around mCurrentFence.
*/
std::shared_ptr<FenceTime> mCurrentFenceTime{FenceTime::NO_FENCE};
/**
* mCurrentTransformMatrix is the transform matrix for the current texture.
* It gets computed by computeTransformMatrix each time updateTexImage is
* called.
*/
float mCurrentTransformMatrix[16];
/**
* mCurrentTimestamp is the timestamp for the current texture. It
* gets set each time updateTexImage is called.
*/
int64_t mCurrentTimestamp;
/**
* mCurrentDataSpace is the dataspace for the current texture. It
* gets set each time updateTexImage is called.
*/
android_dataspace mCurrentDataSpace;
/**
* mCurrentFrameNumber is the frame counter for the current texture.
* It gets set each time updateTexImage is called.
*/
uint64_t mCurrentFrameNumber;
uint32_t mDefaultWidth, mDefaultHeight;
/**
* mFilteringEnabled indicates whether the transform matrix is computed for
* use with bilinear filtering. It defaults to true and is changed by
* setFilteringEnabled().
*/
bool mFilteringEnabled;
/**
* mTexName is the name of the OpenGL texture to which streamed images will
* be bound when updateTexImage is called. It is set at construction time
* and can be changed with a call to attachToContext.
*/
uint32_t mTexName;
/**
* mUseFenceSync indicates whether creation of the EGL_KHR_fence_sync
* extension should be used to prevent buffers from being dequeued before
* it's safe for them to be written. It gets set at construction time and
* never changes.
*/
const bool mUseFenceSync;
/**
* mTexTarget is the GL texture target with which the GL texture object is
* associated. It is set in the constructor and never changed. It is
* almost always GL_TEXTURE_EXTERNAL_OES except for one use case in Android
* Browser. In that case it is set to GL_TEXTURE_2D to allow
* glCopyTexSubImage to read from the texture. This is a hack to work
* around a GL driver limitation on the number of FBO attachments, which the
* browser's tile cache exceeds.
*/
const uint32_t mTexTarget;
/**
* mCurrentTexture is the buffer slot index of the buffer that is currently
* bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
* indicating that no buffer slot is currently bound to the texture. Note,
* however, that a value of INVALID_BUFFER_SLOT does not necessarily mean
* that no buffer is bound to the texture. A call to setBufferCount will
* reset mCurrentTexture to INVALID_BUFFER_SLOT.
*/
int mCurrentTexture;
enum class OpMode { detached, attachedToView, attachedToGL };
/**
* mOpMode indicates whether the SurfaceTexture is currently attached to
* an OpenGL ES context or the HWUI view system. For legacy reasons, this is initialized to,
* "attachedToGL" indicating that the SurfaceTexture is considered to be attached to
* whatever GL context is current at the time of the first updateTexImage call.
* It is set to "detached" by detachFromContext, and then set to "attachedToGL" again by
* attachToContext.
* attachToView/detachFromView are used to attach/detach from HWUI view system.
*/
OpMode mOpMode;
/**
* mEGLConsumer has SurfaceTexture logic used when attached to GL context.
*/
EGLConsumer mEGLConsumer;
/**
* mImageConsumer has SurfaceTexture logic used when attached to HWUI view system.
*/
ImageConsumer mImageConsumer;
friend class ImageConsumer;
friend class EGLConsumer;
};
// ----------------------------------------------------------------------------
} // namespace android