/*
* Copyright (C) 2010 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.
*/
#ifndef ANDROID_GUI_SURFACETEXTURE_H
#define ANDROID_GUI_SURFACETEXTURE_H
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <GLES2/gl2.h>
#include <GLES2/gl2ext.h>
#include <gui/ISurfaceTexture.h>
#include <gui/BufferQueue.h>
#include <gui/ConsumerBase.h>
#include <ui/GraphicBuffer.h>
#include <utils/String8.h>
#include <utils/Vector.h>
#include <utils/threads.h>
#define ANDROID_GRAPHICS_SURFACETEXTURE_JNI_ID "mSurfaceTexture"
namespace android {
// ----------------------------------------------------------------------------
class String8;
class SurfaceTexture : public ConsumerBase {
public:
typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
// SurfaceTexture constructs a new SurfaceTexture object. tex indicates the
// name of the OpenGL ES texture to which images are to be streamed.
// allowSynchronousMode specifies whether or not synchronous mode can be
// enabled. 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 custom bufferQueue can be specified
// if behavior for queue/dequeue/connect etc needs to be customized.
// Otherwise a default BufferQueue will be created and used.
//
// For legacy reasons, 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.
//
// 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.
SurfaceTexture(GLuint tex, bool allowSynchronousMode = true,
GLenum texTarget = GL_TEXTURE_EXTERNAL_OES, bool useFenceSync = true,
const sp<BufferQueue> &bufferQueue = 0);
// updateTexImage sets the image contents of the target texture to that of
// the most recently queued buffer.
//
// This call may only be made while the OpenGL ES context to which the
// target texture belongs is bound to the calling thread.
//
// After calling this method the doGLFenceWait method must be called
// before issuing OpenGL ES commands that access the texture contents.
status_t updateTexImage();
// setReleaseFence stores a fence file descriptor that will signal when the
// current buffer is no longer being read. This fence will be returned to
// the producer when the current buffer is released by updateTexImage().
// Multiple fences can be set for a given buffer; they will be merged into
// a single union fence. The SurfaceTexture will close the file descriptor
// when finished with it.
void setReleaseFence(int fenceFd);
// setDefaultMaxBufferCount sets the default limit on the maximum number
// of buffers that will be allocated at one time. The image producer may
// override the limit.
status_t setDefaultMaxBufferCount(int bufferCount);
// 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]);
// 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();
// 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);
// getCurrentBuffer returns the buffer associated with the current image.
sp<GraphicBuffer> getCurrentBuffer() const;
// getCurrentTextureTarget returns the texture target of the current
// texture as returned by updateTexImage().
GLenum 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;
// doGLFenceWait inserts a wait command into the OpenGL ES command stream
// to ensure that it is safe for future OpenGL ES commands to access the
// current texture buffer. This must be called each time updateTexImage
// is called before issuing OpenGL ES commands that access the texture.
status_t doGLFenceWait() const;
// isSynchronousMode returns whether the SurfaceTexture is currently in
// synchronous mode.
bool isSynchronousMode() const;
// set the name of the SurfaceTexture that will be used to identify it in
// log messages.
void setName(const String8& name);
// These functions call the corresponding BufferQueue implementation
// so the refactoring can proceed smoothly
status_t setDefaultBufferFormat(uint32_t defaultFormat);
status_t setConsumerUsageBits(uint32_t usage);
status_t setTransformHint(uint32_t hint);
virtual status_t setSynchronousMode(bool enabled);
// getBufferQueue returns the BufferQueue object to which this
// SurfaceTexture is connected.
sp<BufferQueue> getBufferQueue() const {
return mBufferQueue;
}
// 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(GLuint tex);
protected:
// abandonLocked overrides the ConsumerBase method to clear
// mCurrentTextureBuf 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, char* buffer,
size_t size) const;
// acquireBufferLocked overrides the ConsumerBase method to update the
// mEglSlots array in addition to the ConsumerBase behavior.
virtual status_t acquireBufferLocked(BufferQueue::BufferItem *item);
// releaseBufferLocked overrides the ConsumerBase method to update the
// mEglSlots array in addition to the ConsumerBase.
virtual status_t releaseBufferLocked(int buf, EGLDisplay display,
EGLSyncKHR eglFence);
static bool isExternalFormat(uint32_t format);
private:
// this version of updateTexImage() takes a functor used to reject or not
// the newly acquired buffer.
// this API is TEMPORARY and intended to be used by SurfaceFlinger only,
// which is why class Layer is made a friend of SurfaceTexture below.
class BufferRejecter {
friend class SurfaceTexture;
virtual bool reject(const sp<GraphicBuffer>& buf,
const BufferQueue::BufferItem& item) = 0;
protected:
virtual ~BufferRejecter() { }
};
friend class Layer;
status_t updateTexImage(BufferRejecter* rejecter, bool skipSync);
// createImage creates a new EGLImage from a GraphicBuffer.
EGLImageKHR createImage(EGLDisplay dpy,
const sp<GraphicBuffer>& graphicBuffer);
// 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.
// mCurrentTextureBuf must not be NULL.
void computeCurrentTransformMatrixLocked();
// doGLFenceWaitLocked inserts a wait command into the OpenGL ES command
// stream to ensure that it is safe for future OpenGL ES commands to
// access the current texture buffer. This must be called each time
// updateTexImage is called before issuing OpenGL ES commands that access
// the texture.
status_t doGLFenceWaitLocked() const;
// syncForReleaseLocked performs the synchronization needed to release the
// current slot from an OpenGL ES context. If needed it will set the
// current slot's fence to guard against a producer accessing the buffer
// before the outstanding accesses have completed.
status_t syncForReleaseLocked(EGLDisplay dpy);
// 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 uint32_t DEFAULT_USAGE_FLAGS = GraphicBuffer::USAGE_HW_TEXTURE;
// mCurrentTextureBuf is the graphic buffer of the current texture. It's
// possible that this buffer is not associated with any buffer slot, so we
// must track it separately in order to support the getCurrentBuffer method.
sp<GraphicBuffer> mCurrentTextureBuf;
// 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 to each time updateTexImage is called.
uint32_t mCurrentScalingMode;
// mCurrentFence is the fence received from BufferQueue in updateTexImage.
sp<Fence> mCurrentFence;
// 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;
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.
GLuint 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 GLenum mTexTarget;
// EGLSlot contains the information and object references that
// SurfaceTexture maintains about a BufferQueue buffer slot.
struct EGLSlot {
EGLSlot()
: mEglImage(EGL_NO_IMAGE_KHR),
mEglFence(EGL_NO_SYNC_KHR) {
}
// mEglImage is the EGLImage created from mGraphicBuffer.
EGLImageKHR mEglImage;
// mFence is the EGL sync object that must signal before the buffer
// associated with this buffer slot may be dequeued. It is initialized
// to EGL_NO_SYNC_KHR when the buffer is created and (optionally, based
// on a compile-time option) set to a new sync object in updateTexImage.
EGLSyncKHR mEglFence;
};
// mEglDisplay is the EGLDisplay with which this SurfaceTexture is currently
// associated. It is intialized to EGL_NO_DISPLAY and gets set to the
// current display when updateTexImage is called for the first time and when
// attachToContext is called.
EGLDisplay mEglDisplay;
// mEglContext is the OpenGL ES context with which this SurfaceTexture is
// currently associated. It is initialized to EGL_NO_CONTEXT and gets set
// to the current GL context when updateTexImage is called for the first
// time and when attachToContext is called.
EGLContext mEglContext;
// mEGLSlots stores the buffers that have been allocated by the BufferQueue
// for each buffer slot. It is initialized to null pointers, and gets
// filled in with the result of BufferQueue::acquire when the
// client dequeues a buffer from a
// slot that has not yet been used. The buffer allocated to a slot will also
// be replaced if the requested buffer usage or geometry differs from that
// of the buffer allocated to a slot.
EGLSlot mEglSlots[BufferQueue::NUM_BUFFER_SLOTS];
// 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;
// mAttached indicates whether the ConsumerBase is currently attached to
// an OpenGL ES context. For legacy reasons, this is initialized to true,
// indicating that the ConsumerBase is considered to be attached to
// whatever context is current at the time of the first updateTexImage call.
// It is set to false by detachFromContext, and then set to true again by
// attachToContext.
bool mAttached;
};
// ----------------------------------------------------------------------------
}; // namespace android
#endif // ANDROID_GUI_SURFACETEXTURE_H