SurfaceTexture.h revision a5c75c01620179ce00812354778a29a80d76e71f
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ANDROID_GUI_SURFACETEXTURE_H 18#define ANDROID_GUI_SURFACETEXTURE_H 19 20#include <EGL/egl.h> 21#include <EGL/eglext.h> 22#include <GLES2/gl2.h> 23 24#include <gui/ISurfaceTexture.h> 25 26#include <ui/GraphicBuffer.h> 27 28#include <utils/threads.h> 29#include <utils/Vector.h> 30 31#define ANDROID_GRAPHICS_SURFACETEXTURE_JNI_ID "mSurfaceTexture" 32 33namespace android { 34// ---------------------------------------------------------------------------- 35 36class IGraphicBufferAlloc; 37 38class SurfaceTexture : public BnSurfaceTexture { 39public: 40 enum { MIN_UNDEQUEUED_BUFFERS = 2 }; 41 enum { MIN_BUFFER_SLOTS = MIN_UNDEQUEUED_BUFFERS + 1 }; 42 enum { NUM_BUFFER_SLOTS = 32 }; 43 44 struct FrameAvailableListener : public virtual RefBase { 45 virtual void onFrameAvailable() = 0; 46 }; 47 48 // tex indicates the name OpenGL texture to which images are to be streamed. 49 // This texture name cannot be changed once the SurfaceTexture is created. 50 SurfaceTexture(GLuint tex); 51 52 virtual ~SurfaceTexture(); 53 54 // setBufferCount updates the number of available buffer slots. After 55 // calling this all buffer slots are both unallocated and owned by the 56 // SurfaceTexture object (i.e. they are not owned by the client). 57 virtual status_t setBufferCount(int bufferCount); 58 59 virtual sp<GraphicBuffer> requestBuffer(int buf, uint32_t w, uint32_t h, 60 uint32_t format, uint32_t usage); 61 62 // dequeueBuffer gets the next buffer slot index for the client to use. If a 63 // buffer slot is available then that slot index is written to the location 64 // pointed to by the buf argument and a status of OK is returned. If no 65 // slot is available then a status of -EBUSY is returned and buf is 66 // unmodified. 67 virtual status_t dequeueBuffer(int *buf); 68 69 // queueBuffer returns a filled buffer to the SurfaceTexture. In addition, a 70 // timestamp must be provided for the buffer. The timestamp is in 71 // nanoseconds, and must be monotonically increasing. Its other semantics 72 // (zero point, etc) are client-dependent and should be documented by the 73 // client. 74 virtual status_t queueBuffer(int buf, int64_t timestamp); 75 virtual void cancelBuffer(int buf); 76 virtual status_t setCrop(const Rect& reg); 77 virtual status_t setTransform(uint32_t transform); 78 79 // updateTexImage sets the image contents of the target texture to that of 80 // the most recently queued buffer. 81 // 82 // This call may only be made while the OpenGL ES context to which the 83 // target texture belongs is bound to the calling thread. 84 status_t updateTexImage(); 85 86 // getTransformMatrix retrieves the 4x4 texture coordinate transform matrix 87 // associated with the texture image set by the most recent call to 88 // updateTexImage. 89 // 90 // This transform matrix maps 2D homogeneous texture coordinates of the form 91 // (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture 92 // coordinate that should be used to sample that location from the texture. 93 // Sampling the texture outside of the range of this transform is undefined. 94 // 95 // This transform is necessary to compensate for transforms that the stream 96 // content producer may implicitly apply to the content. By forcing users of 97 // a SurfaceTexture to apply this transform we avoid performing an extra 98 // copy of the data that would be needed to hide the transform from the 99 // user. 100 // 101 // The matrix is stored in column-major order so that it may be passed 102 // directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv 103 // functions. 104 void getTransformMatrix(float mtx[16]); 105 106 // getTimestamp retrieves the timestamp associated with the texture image 107 // set by the most recent call to updateTexImage. 108 // 109 // The timestamp is in nanoseconds, and is monotonically increasing. Its 110 // other semantics (zero point, etc) are source-dependent and should be 111 // documented by the source. 112 int64_t getTimestamp(); 113 114 // setFrameAvailableListener sets the listener object that will be notified 115 // when a new frame becomes available. 116 void setFrameAvailableListener(const sp<FrameAvailableListener>& l); 117 118 // getAllocator retrieves the binder object that must be referenced as long 119 // as the GraphicBuffers dequeued from this SurfaceTexture are referenced. 120 // Holding this binder reference prevents SurfaceFlinger from freeing the 121 // buffers before the client is done with them. 122 sp<IBinder> getAllocator(); 123 124 // setDefaultBufferSize is used to set the size of buffers returned by 125 // requestBuffers when a with and height of zero is requested. 126 // A call to setDefaultBufferSize() may trigger requestBuffers() to 127 // be called from the client. 128 status_t setDefaultBufferSize(uint32_t w, uint32_t h); 129 130private: 131 132 // freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for 133 // all slots. 134 void freeAllBuffers(); 135 136 // createImage creates a new EGLImage from a GraphicBuffer. 137 EGLImageKHR createImage(EGLDisplay dpy, 138 const sp<GraphicBuffer>& graphicBuffer); 139 140 enum { INVALID_BUFFER_SLOT = -1 }; 141 142 struct BufferSlot { 143 // mGraphicBuffer points to the buffer allocated for this slot or is NULL 144 // if no buffer has been allocated. 145 sp<GraphicBuffer> mGraphicBuffer; 146 147 // mEglImage is the EGLImage created from mGraphicBuffer. 148 EGLImageKHR mEglImage; 149 150 // mEglDisplay is the EGLDisplay used to create mEglImage. 151 EGLDisplay mEglDisplay; 152 153 // mOwnedByClient indicates whether the slot is currently accessible to a 154 // client and should not be used by the SurfaceTexture object. It gets 155 // set to true when dequeueBuffer returns the slot and is reset to false 156 // when the client calls either queueBuffer or cancelBuffer on the slot. 157 bool mOwnedByClient; 158 }; 159 160 // mSlots is the array of buffer slots that must be mirrored on the client 161 // side. This allows buffer ownership to be transferred between the client 162 // and server without sending a GraphicBuffer over binder. The entire array 163 // is initialized to NULL at construction time, and buffers are allocated 164 // for a slot when requestBuffer is called with that slot's index. 165 BufferSlot mSlots[NUM_BUFFER_SLOTS]; 166 167 // mDefaultWidth holds the default width of allocated buffers. It is used 168 // in requestBuffers() if a width and height of zero is specified. 169 uint32_t mDefaultWidth; 170 171 // mDefaultHeight holds the default height of allocated buffers. It is used 172 // in requestBuffers() if a width and height of zero is specified. 173 uint32_t mDefaultHeight; 174 175 // mPixelFormat holds the pixel format of allocated buffers. It is used 176 // in requestBuffers() if a format of zero is specified. 177 uint32_t mPixelFormat; 178 179 // mUseDefaultSize indicates whether or not the default size should be used 180 // that is, if the last requestBuffer has been called with both width 181 // and height null. 182 bool mUseDefaultSize; 183 184 // mBufferCount is the number of buffer slots that the client and server 185 // must maintain. It defaults to MIN_BUFFER_SLOTS and can be changed by 186 // calling setBufferCount. 187 int mBufferCount; 188 189 // mCurrentTexture is the buffer slot index of the buffer that is currently 190 // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT, 191 // indicating that no buffer slot is currently bound to the texture. Note, 192 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean 193 // that no buffer is bound to the texture. A call to setBufferCount will 194 // reset mCurrentTexture to INVALID_BUFFER_SLOT. 195 int mCurrentTexture; 196 197 // mCurrentTextureBuf is the graphic buffer of the current texture. It's 198 // possible that this buffer is not associated with any buffer slot, so we 199 // must track it separately in order to properly use 200 // IGraphicBufferAlloc::freeAllGraphicBuffersExcept. 201 sp<GraphicBuffer> mCurrentTextureBuf; 202 203 // mCurrentCrop is the crop rectangle that applies to the current texture. 204 // It gets set to mLastQueuedCrop each time updateTexImage is called. 205 Rect mCurrentCrop; 206 207 // mCurrentTransform is the transform identifier for the current texture. It 208 // gets set to mLastQueuedTransform each time updateTexImage is called. 209 uint32_t mCurrentTransform; 210 211 // mCurrentTimestamp is the timestamp for the current texture. It 212 // gets set to mLastQueuedTimestamp each time updateTexImage is called. 213 int64_t mCurrentTimestamp; 214 215 // mLastQueued is the buffer slot index of the most recently enqueued buffer. 216 // At construction time it is initialized to INVALID_BUFFER_SLOT, and is 217 // updated each time queueBuffer is called. 218 int mLastQueued; 219 220 // mLastQueuedCrop is the crop rectangle for the buffer that was most 221 // recently queued. This gets set to mNextCrop each time queueBuffer gets 222 // called. 223 Rect mLastQueuedCrop; 224 225 // mLastQueuedTransform is the transform identifier for the buffer that was 226 // most recently queued. This gets set to mNextTransform each time 227 // queueBuffer gets called. 228 uint32_t mLastQueuedTransform; 229 230 // mLastQueuedTimestamp is the timestamp for the buffer that was most 231 // recently queued. This gets set by queueBuffer. 232 int64_t mLastQueuedTimestamp; 233 234 // mNextCrop is the crop rectangle that will be used for the next buffer 235 // that gets queued. It is set by calling setCrop. 236 Rect mNextCrop; 237 238 // mNextTransform is the transform identifier that will be used for the next 239 // buffer that gets queued. It is set by calling setTransform. 240 uint32_t mNextTransform; 241 242 // mTexName is the name of the OpenGL texture to which streamed images will 243 // be bound when updateTexImage is called. It is set at construction time 244 // changed with a call to setTexName. 245 const GLuint mTexName; 246 247 // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to 248 // allocate new GraphicBuffer objects. 249 sp<IGraphicBufferAlloc> mGraphicBufferAlloc; 250 251 // mAllocdBuffers is mirror of the list of buffers that SurfaceFlinger is 252 // referencing. This is kept so that gralloc implementations do not need to 253 // properly handle the case where SurfaceFlinger no longer holds a reference 254 // to a buffer, but other processes do. 255 Vector<sp<GraphicBuffer> > mAllocdBuffers; 256 257 // mFrameAvailableListener is the listener object that will be called when a 258 // new frame becomes available. If it is not NULL it will be called from 259 // queueBuffer. 260 sp<FrameAvailableListener> mFrameAvailableListener; 261 262 // mMutex is the mutex used to prevent concurrent access to the member 263 // variables of SurfaceTexture objects. It must be locked whenever the 264 // member variables are accessed. 265 Mutex mMutex; 266}; 267 268// ---------------------------------------------------------------------------- 269}; // namespace android 270 271#endif // ANDROID_GUI_SURFACETEXTURE_H 272