SurfaceTexture.h revision c04f153353cdb0d291297d10452239f791d3fd2b
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); 60 61 // dequeueBuffer gets the next buffer slot index for the client to use. If a 62 // buffer slot is available then that slot index is written to the location 63 // pointed to by the buf argument and a status of OK is returned. If no 64 // slot is available then a status of -EBUSY is returned and buf is 65 // unmodified. 66 virtual status_t dequeueBuffer(int *buf, uint32_t w, uint32_t h, 67 uint32_t format, uint32_t usage); 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); 129 130 // getCurrentBuffer returns the buffer associated with the current image. 131 sp<GraphicBuffer> getCurrentBuffer() const; 132 133 // getCurrentTextureTarget returns the texture target of the current 134 // texture as returned by updateTexImage(). 135 GLenum getCurrentTextureTarget() const; 136 137 // getCurrentCrop returns the cropping rectangle of the current buffer 138 Rect getCurrentCrop() const; 139 140 // getCurrentTransform returns the transform of the current buffer 141 uint32_t getCurrentTransform() const; 142 143protected: 144 145 // freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for 146 // all slots. 147 void freeAllBuffers(); 148 static bool isExternalFormat(uint32_t format); 149 static GLenum getTextureTarget(uint32_t format); 150 151private: 152 153 // createImage creates a new EGLImage from a GraphicBuffer. 154 EGLImageKHR createImage(EGLDisplay dpy, 155 const sp<GraphicBuffer>& graphicBuffer); 156 157 enum { INVALID_BUFFER_SLOT = -1 }; 158 159 struct BufferSlot { 160 // mGraphicBuffer points to the buffer allocated for this slot or is NULL 161 // if no buffer has been allocated. 162 sp<GraphicBuffer> mGraphicBuffer; 163 164 // mEglImage is the EGLImage created from mGraphicBuffer. 165 EGLImageKHR mEglImage; 166 167 // mEglDisplay is the EGLDisplay used to create mEglImage. 168 EGLDisplay mEglDisplay; 169 170 // mOwnedByClient indicates whether the slot is currently accessible to a 171 // client and should not be used by the SurfaceTexture object. It gets 172 // set to true when dequeueBuffer returns the slot and is reset to false 173 // when the client calls either queueBuffer or cancelBuffer on the slot. 174 bool mOwnedByClient; 175 }; 176 177 // mSlots is the array of buffer slots that must be mirrored on the client 178 // side. This allows buffer ownership to be transferred between the client 179 // and server without sending a GraphicBuffer over binder. The entire array 180 // is initialized to NULL at construction time, and buffers are allocated 181 // for a slot when requestBuffer is called with that slot's index. 182 BufferSlot mSlots[NUM_BUFFER_SLOTS]; 183 184 // mDefaultWidth holds the default width of allocated buffers. It is used 185 // in requestBuffers() if a width and height of zero is specified. 186 uint32_t mDefaultWidth; 187 188 // mDefaultHeight holds the default height of allocated buffers. It is used 189 // in requestBuffers() if a width and height of zero is specified. 190 uint32_t mDefaultHeight; 191 192 // mPixelFormat holds the pixel format of allocated buffers. It is used 193 // in requestBuffers() if a format of zero is specified. 194 uint32_t mPixelFormat; 195 196 // mBufferCount is the number of buffer slots that the client and server 197 // must maintain. It defaults to MIN_BUFFER_SLOTS and can be changed by 198 // calling setBufferCount. 199 int mBufferCount; 200 201 // mCurrentTexture is the buffer slot index of the buffer that is currently 202 // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT, 203 // indicating that no buffer slot is currently bound to the texture. Note, 204 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean 205 // that no buffer is bound to the texture. A call to setBufferCount will 206 // reset mCurrentTexture to INVALID_BUFFER_SLOT. 207 int mCurrentTexture; 208 209 // mCurrentTextureTarget is the GLES texture target to be used with the 210 // current texture. 211 GLenum mCurrentTextureTarget; 212 213 // mCurrentTextureBuf is the graphic buffer of the current texture. It's 214 // possible that this buffer is not associated with any buffer slot, so we 215 // must track it separately in order to properly use 216 // IGraphicBufferAlloc::freeAllGraphicBuffersExcept. 217 sp<GraphicBuffer> mCurrentTextureBuf; 218 219 // mCurrentCrop is the crop rectangle that applies to the current texture. 220 // It gets set to mLastQueuedCrop each time updateTexImage is called. 221 Rect mCurrentCrop; 222 223 // mCurrentTransform is the transform identifier for the current texture. It 224 // gets set to mLastQueuedTransform each time updateTexImage is called. 225 uint32_t mCurrentTransform; 226 227 // mCurrentTimestamp is the timestamp for the current texture. It 228 // gets set to mLastQueuedTimestamp each time updateTexImage is called. 229 int64_t mCurrentTimestamp; 230 231 // mLastQueued is the buffer slot index of the most recently enqueued buffer. 232 // At construction time it is initialized to INVALID_BUFFER_SLOT, and is 233 // updated each time queueBuffer is called. 234 int mLastQueued; 235 236 // mLastQueuedCrop is the crop rectangle for the buffer that was most 237 // recently queued. This gets set to mNextCrop each time queueBuffer gets 238 // called. 239 Rect mLastQueuedCrop; 240 241 // mLastQueuedTransform is the transform identifier for the buffer that was 242 // most recently queued. This gets set to mNextTransform each time 243 // queueBuffer gets called. 244 uint32_t mLastQueuedTransform; 245 246 // mLastQueuedTimestamp is the timestamp for the buffer that was most 247 // recently queued. This gets set by queueBuffer. 248 int64_t mLastQueuedTimestamp; 249 250 // mNextCrop is the crop rectangle that will be used for the next buffer 251 // that gets queued. It is set by calling setCrop. 252 Rect mNextCrop; 253 254 // mNextTransform is the transform identifier that will be used for the next 255 // buffer that gets queued. It is set by calling setTransform. 256 uint32_t mNextTransform; 257 258 // mTexName is the name of the OpenGL texture to which streamed images will 259 // be bound when updateTexImage is called. It is set at construction time 260 // changed with a call to setTexName. 261 const GLuint mTexName; 262 263 // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to 264 // allocate new GraphicBuffer objects. 265 sp<IGraphicBufferAlloc> mGraphicBufferAlloc; 266 267 // mFrameAvailableListener is the listener object that will be called when a 268 // new frame becomes available. If it is not NULL it will be called from 269 // queueBuffer. 270 sp<FrameAvailableListener> mFrameAvailableListener; 271 272 // mMutex is the mutex used to prevent concurrent access to the member 273 // variables of SurfaceTexture objects. It must be locked whenever the 274 // member variables are accessed. 275 mutable Mutex mMutex; 276}; 277 278// ---------------------------------------------------------------------------- 279}; // namespace android 280 281#endif // ANDROID_GUI_SURFACETEXTURE_H 282