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Diffstat (limited to 'include/gui/GLConsumer.h')
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diff --git a/include/gui/GLConsumer.h b/include/gui/GLConsumer.h new file mode 100644 index 0000000..e0fa893 --- /dev/null +++ b/include/gui/GLConsumer.h @@ -0,0 +1,432 @@ +/* + * 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_CONSUMER_H +#define ANDROID_GUI_CONSUMER_H + +#include <EGL/egl.h> +#include <EGL/eglext.h> +#include <GLES2/gl2.h> +#include <GLES2/gl2ext.h> + +#include <gui/IGraphicBufferProducer.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" +#define ANDROID_GRAPHICS_FRAMEAVAILABLELISTENER_JNI_ID \ + "mFrameAvailableListener" + +namespace android { +// ---------------------------------------------------------------------------- + + +class String8; + +/* + * GLConsumer consumes buffers of graphics data from a BufferQueue, + * and makes them available to OpenGL as a texture. + * + * A typical usage pattern is to set up the GLConsumer 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. + * + * By default, the texture is attached to the GL_TEXTURE_EXTERNAL_OES + * texture target, in the EGL context of the first thread that calls + * updateTexImage(). + * + * This class was previously called SurfaceTexture. + */ +class GLConsumer : public ConsumerBase { +public: + typedef ConsumerBase::FrameAvailableListener FrameAvailableListener; + + // GLConsumer constructs a new GLConsumer 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 GLConsumer 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 GLConsumer 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 GLConsumer 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. + GLConsumer(GLuint tex, bool allowSynchronousMode = true, + GLenum texTarget = GL_TEXTURE_EXTERNAL_OES, bool useFenceSync = true, + const sp<BufferQueue> &bufferQueue = 0); + + // 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(); + + // 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 GLConsumer 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 GLConsumer 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. + status_t doGLFenceWait() const; + + // isSynchronousMode returns whether the GLConsumer is currently in + // synchronous mode. + bool isSynchronousMode() const; + + // set the name of the GLConsumer 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 + // GLConsumer is connected. + sp<BufferQueue> getBufferQueue() const { + return mBufferQueue; + } + + // detachFromContext detaches the GLConsumer 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 GLConsumer 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 GLConsumer has been detached from the OpenGL ES + // context calls to updateTexImage will fail returning INVALID_OPERATION + // until the GLConsumer is attached to a new OpenGL ES context using the + // attachToContext method. + status_t detachFromContext(); + + // attachToContext attaches a GLConsumer that is currently in the + // 'detached' state to the current OpenGL ES context. A GLConsumer 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 + // GLConsumer 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 GLConsumer- + // 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); + + status_t releaseBufferLocked(int buf, EGLSyncKHR eglFence) { + return releaseBufferLocked(buf, mEglDisplay, eglFence); + } + + static bool isExternalFormat(uint32_t format); + + // This releases the buffer in the slot referenced by mCurrentTexture, + // then updates state to refer to the BufferItem, which must be a + // newly-acquired buffer. + status_t releaseAndUpdateLocked(const BufferQueue::BufferItem& item); + + // Binds mTexName and the current buffer to mTexTarget. Uses + // mCurrentTexture if it's set, mCurrentTextureBuf if not. If the + // bind succeeds, this calls doGLFenceWait. + status_t bindTextureImageLocked(); + + // Gets the current EGLDisplay and EGLContext values, and compares them + // to mEglDisplay and mEglContext. If the fields have been previously + // set, the values must match; if not, the fields are set to the current + // values. + status_t checkAndUpdateEglStateLocked(); + + // If set, GLConsumer will use the EGL_ANDROID_native_fence_sync + // extension to create Android native fences for GLES activity. + static const bool sUseNativeFenceSync; + +private: + // 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. + 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); + + // Normally, when we bind a buffer to a texture target, we bind a buffer + // that is referenced by an entry in mEglSlots. In some situations we + // have a buffer in mCurrentTextureBuf, but no corresponding entry for + // it in our slot array. bindUnslottedBuffer handles that situation by + // binding the buffer without touching the EglSlots. + status_t bindUnslottedBufferLocked(EGLDisplay dpy); + + // The default consumer usage flags that GLConsumer always sets on its + // BufferQueue instance; these will be OR:d with any additional flags passed + // from the GLConsumer user. In particular, GLConsumer 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 + // GLConsumer 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 GLConsumer 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 GLConsumer 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_CONSUMER_H |