/* * 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 <gui/ISurfaceTexture.h> #include <ui/GraphicBuffer.h> #include <utils/threads.h> #include <utils/Vector.h> #define ANDROID_GRAPHICS_SURFACETEXTURE_JNI_ID "mSurfaceTexture" namespace android { // ---------------------------------------------------------------------------- class IGraphicBufferAlloc; class SurfaceTexture : public BnSurfaceTexture { public: enum { MIN_BUFFER_SLOTS = 3 }; enum { NUM_BUFFER_SLOTS = 32 }; struct FrameAvailableListener : public virtual RefBase { virtual void onFrameAvailable() = 0; }; // tex indicates the name OpenGL texture to which images are to be streamed. // This texture name cannot be changed once the SurfaceTexture is created. SurfaceTexture(GLuint tex); virtual ~SurfaceTexture(); // setBufferCount updates the number of available buffer slots. After // calling this all buffer slots are both unallocated and owned by the // SurfaceTexture object (i.e. they are not owned by the client). virtual status_t setBufferCount(int bufferCount); virtual sp<GraphicBuffer> requestBuffer(int buf, uint32_t w, uint32_t h, uint32_t format, uint32_t usage); // dequeueBuffer gets the next buffer slot index for the client to use. If a // buffer slot is available then that slot index is written to the location // pointed to by the buf argument and a status of OK is returned. If no // slot is available then a status of -EBUSY is returned and buf is // unmodified. virtual status_t dequeueBuffer(int *buf); virtual status_t queueBuffer(int buf); virtual void cancelBuffer(int buf); virtual status_t setCrop(const Rect& reg); virtual status_t setTransform(uint32_t transform); // 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. status_t updateTexImage(); // 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]); // setFrameAvailableListener sets the listener object that will be notified // when a new frame becomes available. void setFrameAvailableListener(const sp<FrameAvailableListener>& l); private: // freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for // all slots. void freeAllBuffers(); // createImage creates a new EGLImage from a GraphicBuffer. EGLImageKHR createImage(EGLDisplay dpy, const sp<GraphicBuffer>& graphicBuffer); enum { INVALID_BUFFER_SLOT = -1 }; struct BufferSlot { // mGraphicBuffer points to the buffer allocated for this slot or is NULL // if no buffer has been allocated. sp<GraphicBuffer> mGraphicBuffer; // mEglImage is the EGLImage created from mGraphicBuffer. EGLImageKHR mEglImage; // mEglDisplay is the EGLDisplay used to create mEglImage. EGLDisplay mEglDisplay; // mOwnedByClient indicates whether the slot is currently accessible to a // client and should not be used by the SurfaceTexture object. It gets // set to true when dequeueBuffer returns the slot and is reset to false // when the client calls either queueBuffer or cancelBuffer on the slot. bool mOwnedByClient; }; // mSlots is the array of buffer slots that must be mirrored on the client // side. This allows buffer ownership to be transferred between the client // and server without sending a GraphicBuffer over binder. The entire array // is initialized to NULL at construction time, and buffers are allocated // for a slot when requestBuffer is called with that slot's index. BufferSlot mSlots[NUM_BUFFER_SLOTS]; // mBufferCount is the number of buffer slots that the client and server // must maintain. It defaults to MIN_BUFFER_SLOTS and can be changed by // calling setBufferCount. int mBufferCount; // 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; // 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 properly use // IGraphicBufferAlloc::freeAllGraphicBuffersExcept. sp<GraphicBuffer> mCurrentTextureBuf; // mCurrentCrop is the crop rectangle that applies to the current texture. // It gets set to mLastQueuedCrop each time updateTexImage is called. Rect mCurrentCrop; // mCurrentTransform is the transform identifier for the current texture. It // gets set to mLastQueuedTransform each time updateTexImage is called. uint32_t mCurrentTransform; // mLastQueued is the buffer slot index of the most recently enqueued buffer. // At construction time it is initialized to INVALID_BUFFER_SLOT, and is // updated each time queueBuffer is called. int mLastQueued; // mLastQueuedCrop is the crop rectangle for the buffer that was most // recently queued. This gets set to mNextCrop each time queueBuffer gets // called. Rect mLastQueuedCrop; // mLastQueuedTransform is the transform identifier for the buffer that was // most recently queued. This gets set to mNextTransform each time // queueBuffer gets called. uint32_t mLastQueuedTransform; // mNextCrop is the crop rectangle that will be used for the next buffer // that gets queued. It is set by calling setCrop. Rect mNextCrop; // mNextTransform is the transform identifier that will be used for the next // buffer that gets queued. It is set by calling setTransform. uint32_t mNextTransform; // 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 // changed with a call to setTexName. const GLuint mTexName; // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to // allocate new GraphicBuffer objects. sp<IGraphicBufferAlloc> mGraphicBufferAlloc; // mAllocdBuffers is mirror of the list of buffers that SurfaceFlinger is // referencing. This is kept so that gralloc implementations do not need to // properly handle the case where SurfaceFlinger no longer holds a reference // to a buffer, but other processes do. Vector<sp<GraphicBuffer> > mAllocdBuffers; // mFrameAvailableListener is the listener object that will be called when a // new frame becomes available. If it is not NULL it will be called from // queueBuffer. sp<FrameAvailableListener> mFrameAvailableListener; // mMutex is the mutex used to prevent concurrent access to the member // variables of SurfaceTexture objects. It must be locked whenever the // member variables are accessed. Mutex mMutex; }; // ---------------------------------------------------------------------------- }; // namespace android #endif // ANDROID_GUI_SURFACETEXTURE_H