SurfaceTexture.h revision eafabcdc1639fb96062d9e3c39b0ae27b0238ae1
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 virtual int query(int what, int* value); 80 81 // updateTexImage sets the image contents of the target texture to that of 82 // the most recently queued buffer. 83 // 84 // This call may only be made while the OpenGL ES context to which the 85 // target texture belongs is bound to the calling thread. 86 status_t updateTexImage(); 87 88 // getTransformMatrix retrieves the 4x4 texture coordinate transform matrix 89 // associated with the texture image set by the most recent call to 90 // updateTexImage. 91 // 92 // This transform matrix maps 2D homogeneous texture coordinates of the form 93 // (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture 94 // coordinate that should be used to sample that location from the texture. 95 // Sampling the texture outside of the range of this transform is undefined. 96 // 97 // This transform is necessary to compensate for transforms that the stream 98 // content producer may implicitly apply to the content. By forcing users of 99 // a SurfaceTexture to apply this transform we avoid performing an extra 100 // copy of the data that would be needed to hide the transform from the 101 // user. 102 // 103 // The matrix is stored in column-major order so that it may be passed 104 // directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv 105 // functions. 106 void getTransformMatrix(float mtx[16]); 107 108 // getTimestamp retrieves the timestamp associated with the texture image 109 // set by the most recent call to updateTexImage. 110 // 111 // The timestamp is in nanoseconds, and is monotonically increasing. Its 112 // other semantics (zero point, etc) are source-dependent and should be 113 // documented by the source. 114 int64_t getTimestamp(); 115 116 // setFrameAvailableListener sets the listener object that will be notified 117 // when a new frame becomes available. 118 void setFrameAvailableListener(const sp<FrameAvailableListener>& l); 119 120 // getAllocator retrieves the binder object that must be referenced as long 121 // as the GraphicBuffers dequeued from this SurfaceTexture are referenced. 122 // Holding this binder reference prevents SurfaceFlinger from freeing the 123 // buffers before the client is done with them. 124 sp<IBinder> getAllocator(); 125 126 // setDefaultBufferSize is used to set the size of buffers returned by 127 // requestBuffers when a with and height of zero is requested. 128 // A call to setDefaultBufferSize() may trigger requestBuffers() to 129 // be called from the client. 130 status_t setDefaultBufferSize(uint32_t w, uint32_t h); 131 132 // getCurrentBuffer returns the buffer associated with the current image. 133 sp<GraphicBuffer> getCurrentBuffer() const; 134 135 // getCurrentTextureTarget returns the texture target of the current 136 // texture as returned by updateTexImage(). 137 GLenum getCurrentTextureTarget() const; 138 139 // getCurrentCrop returns the cropping rectangle of the current buffer 140 Rect getCurrentCrop() const; 141 142 // getCurrentTransform returns the transform of the current buffer 143 uint32_t getCurrentTransform() const; 144 145protected: 146 147 // freeAllBuffers frees the resources (both GraphicBuffer and EGLImage) for 148 // all slots. 149 void freeAllBuffers(); 150 static bool isExternalFormat(uint32_t format); 151 static GLenum getTextureTarget(uint32_t format); 152 153private: 154 155 // createImage creates a new EGLImage from a GraphicBuffer. 156 EGLImageKHR createImage(EGLDisplay dpy, 157 const sp<GraphicBuffer>& graphicBuffer); 158 159 enum { INVALID_BUFFER_SLOT = -1 }; 160 161 struct BufferSlot { 162 // mGraphicBuffer points to the buffer allocated for this slot or is NULL 163 // if no buffer has been allocated. 164 sp<GraphicBuffer> mGraphicBuffer; 165 166 // mEglImage is the EGLImage created from mGraphicBuffer. 167 EGLImageKHR mEglImage; 168 169 // mEglDisplay is the EGLDisplay used to create mEglImage. 170 EGLDisplay mEglDisplay; 171 172 // mOwnedByClient indicates whether the slot is currently accessible to a 173 // client and should not be used by the SurfaceTexture object. It gets 174 // set to true when dequeueBuffer returns the slot and is reset to false 175 // when the client calls either queueBuffer or cancelBuffer on the slot. 176 bool mOwnedByClient; 177 }; 178 179 // mSlots is the array of buffer slots that must be mirrored on the client 180 // side. This allows buffer ownership to be transferred between the client 181 // and server without sending a GraphicBuffer over binder. The entire array 182 // is initialized to NULL at construction time, and buffers are allocated 183 // for a slot when requestBuffer is called with that slot's index. 184 BufferSlot mSlots[NUM_BUFFER_SLOTS]; 185 186 // mDefaultWidth holds the default width of allocated buffers. It is used 187 // in requestBuffers() if a width and height of zero is specified. 188 uint32_t mDefaultWidth; 189 190 // mDefaultHeight holds the default height of allocated buffers. It is used 191 // in requestBuffers() if a width and height of zero is specified. 192 uint32_t mDefaultHeight; 193 194 // mPixelFormat holds the pixel format of allocated buffers. It is used 195 // in requestBuffers() if a format of zero is specified. 196 uint32_t mPixelFormat; 197 198 // mBufferCount is the number of buffer slots that the client and server 199 // must maintain. It defaults to MIN_BUFFER_SLOTS and can be changed by 200 // calling setBufferCount. 201 int mBufferCount; 202 203 // mCurrentTexture is the buffer slot index of the buffer that is currently 204 // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT, 205 // indicating that no buffer slot is currently bound to the texture. Note, 206 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean 207 // that no buffer is bound to the texture. A call to setBufferCount will 208 // reset mCurrentTexture to INVALID_BUFFER_SLOT. 209 int mCurrentTexture; 210 211 // mCurrentTextureTarget is the GLES texture target to be used with the 212 // current texture. 213 GLenum mCurrentTextureTarget; 214 215 // mCurrentTextureBuf is the graphic buffer of the current texture. It's 216 // possible that this buffer is not associated with any buffer slot, so we 217 // must track it separately in order to properly use 218 // IGraphicBufferAlloc::freeAllGraphicBuffersExcept. 219 sp<GraphicBuffer> mCurrentTextureBuf; 220 221 // mCurrentCrop is the crop rectangle that applies to the current texture. 222 // It gets set to mLastQueuedCrop each time updateTexImage is called. 223 Rect mCurrentCrop; 224 225 // mCurrentTransform is the transform identifier for the current texture. It 226 // gets set to mLastQueuedTransform each time updateTexImage is called. 227 uint32_t mCurrentTransform; 228 229 // mCurrentTimestamp is the timestamp for the current texture. It 230 // gets set to mLastQueuedTimestamp each time updateTexImage is called. 231 int64_t mCurrentTimestamp; 232 233 // mLastQueued is the buffer slot index of the most recently enqueued buffer. 234 // At construction time it is initialized to INVALID_BUFFER_SLOT, and is 235 // updated each time queueBuffer is called. 236 int mLastQueued; 237 238 // mLastQueuedCrop is the crop rectangle for the buffer that was most 239 // recently queued. This gets set to mNextCrop each time queueBuffer gets 240 // called. 241 Rect mLastQueuedCrop; 242 243 // mLastQueuedTransform is the transform identifier for the buffer that was 244 // most recently queued. This gets set to mNextTransform each time 245 // queueBuffer gets called. 246 uint32_t mLastQueuedTransform; 247 248 // mLastQueuedTimestamp is the timestamp for the buffer that was most 249 // recently queued. This gets set by queueBuffer. 250 int64_t mLastQueuedTimestamp; 251 252 // mNextCrop is the crop rectangle that will be used for the next buffer 253 // that gets queued. It is set by calling setCrop. 254 Rect mNextCrop; 255 256 // mNextTransform is the transform identifier that will be used for the next 257 // buffer that gets queued. It is set by calling setTransform. 258 uint32_t mNextTransform; 259 260 // mTexName is the name of the OpenGL texture to which streamed images will 261 // be bound when updateTexImage is called. It is set at construction time 262 // changed with a call to setTexName. 263 const GLuint mTexName; 264 265 // mGraphicBufferAlloc is the connection to SurfaceFlinger that is used to 266 // allocate new GraphicBuffer objects. 267 sp<IGraphicBufferAlloc> mGraphicBufferAlloc; 268 269 // mFrameAvailableListener is the listener object that will be called when a 270 // new frame becomes available. If it is not NULL it will be called from 271 // queueBuffer. 272 sp<FrameAvailableListener> mFrameAvailableListener; 273 274 // mMutex is the mutex used to prevent concurrent access to the member 275 // variables of SurfaceTexture objects. It must be locked whenever the 276 // member variables are accessed. 277 mutable Mutex mMutex; 278}; 279 280// ---------------------------------------------------------------------------- 281}; // namespace android 282 283#endif // ANDROID_GUI_SURFACETEXTURE_H 284