2 * Copyright (C) 2010 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef ANDROID_GUI_SURFACETEXTURE_H
18 #define ANDROID_GUI_SURFACETEXTURE_H
21 #include <EGL/eglext.h>
22 #include <GLES2/gl2.h>
23 #include <GLES2/gl2ext.h>
25 #include <gui/ISurfaceTexture.h>
26 #include <gui/BufferQueue.h>
27 #include <gui/ConsumerBase.h>
29 #include <ui/GraphicBuffer.h>
31 #include <utils/String8.h>
32 #include <utils/Vector.h>
33 #include <utils/threads.h>
35 #define ANDROID_GRAPHICS_SURFACETEXTURE_JNI_ID "mSurfaceTexture"
38 // ----------------------------------------------------------------------------
43 class SurfaceTexture : public ConsumerBase {
45 typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
47 // SurfaceTexture constructs a new SurfaceTexture object. tex indicates the
48 // name of the OpenGL ES texture to which images are to be streamed.
49 // allowSynchronousMode specifies whether or not synchronous mode can be
50 // enabled. texTarget specifies the OpenGL ES texture target to which the
51 // texture will be bound in updateTexImage. useFenceSync specifies whether
52 // fences should be used to synchronize access to buffers if that behavior
53 // is enabled at compile-time. A custom bufferQueue can be specified
54 // if behavior for queue/dequeue/connect etc needs to be customized.
55 // Otherwise a default BufferQueue will be created and used.
57 // For legacy reasons, the SurfaceTexture is created in a state where it is
58 // considered attached to an OpenGL ES context for the purposes of the
59 // attachToContext and detachFromContext methods. However, despite being
60 // considered "attached" to a context, the specific OpenGL ES context
61 // doesn't get latched until the first call to updateTexImage. After that
62 // point, all calls to updateTexImage must be made with the same OpenGL ES
65 // A SurfaceTexture may be detached from one OpenGL ES context and then
66 // attached to a different context using the detachFromContext and
67 // attachToContext methods, respectively. The intention of these methods is
68 // purely to allow a SurfaceTexture to be transferred from one consumer
69 // context to another. If such a transfer is not needed there is no
70 // requirement that either of these methods be called.
71 SurfaceTexture(GLuint tex, bool allowSynchronousMode = true,
72 GLenum texTarget = GL_TEXTURE_EXTERNAL_OES, bool useFenceSync = true,
73 const sp<BufferQueue> &bufferQueue = 0);
75 // updateTexImage sets the image contents of the target texture to that of
76 // the most recently queued buffer.
78 // This call may only be made while the OpenGL ES context to which the
79 // target texture belongs is bound to the calling thread.
80 status_t updateTexImage();
82 // setReleaseFence stores a fence file descriptor that will signal when the
83 // current buffer is no longer being read. This fence will be returned to
84 // the producer when the current buffer is released by updateTexImage().
85 // Multiple fences can be set for a given buffer; they will be merged into
86 // a single union fence. The SurfaceTexture will close the file descriptor
87 // when finished with it.
88 void setReleaseFence(int fenceFd);
90 // setBufferCountServer set the buffer count. If the client has requested
91 // a buffer count using setBufferCount, the server-buffer count will
92 // take effect once the client sets the count back to zero.
93 status_t setBufferCountServer(int bufferCount);
95 // getTransformMatrix retrieves the 4x4 texture coordinate transform matrix
96 // associated with the texture image set by the most recent call to
99 // This transform matrix maps 2D homogeneous texture coordinates of the form
100 // (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture
101 // coordinate that should be used to sample that location from the texture.
102 // Sampling the texture outside of the range of this transform is undefined.
104 // This transform is necessary to compensate for transforms that the stream
105 // content producer may implicitly apply to the content. By forcing users of
106 // a SurfaceTexture to apply this transform we avoid performing an extra
107 // copy of the data that would be needed to hide the transform from the
110 // The matrix is stored in column-major order so that it may be passed
111 // directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv
113 void getTransformMatrix(float mtx[16]);
115 // getTimestamp retrieves the timestamp associated with the texture image
116 // set by the most recent call to updateTexImage.
118 // The timestamp is in nanoseconds, and is monotonically increasing. Its
119 // other semantics (zero point, etc) are source-dependent and should be
120 // documented by the source.
121 int64_t getTimestamp();
123 // setDefaultBufferSize is used to set the size of buffers returned by
124 // requestBuffers when a with and height of zero is requested.
125 // A call to setDefaultBufferSize() may trigger requestBuffers() to
126 // be called from the client.
127 // The width and height parameters must be no greater than the minimum of
128 // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
129 // An error due to invalid dimensions might not be reported until
130 // updateTexImage() is called.
131 status_t setDefaultBufferSize(uint32_t width, uint32_t height);
133 // setFilteringEnabled sets whether the transform matrix should be computed
134 // for use with bilinear filtering.
135 void setFilteringEnabled(bool enabled);
137 // getCurrentBuffer returns the buffer associated with the current image.
138 sp<GraphicBuffer> getCurrentBuffer() const;
140 // getCurrentTextureTarget returns the texture target of the current
141 // texture as returned by updateTexImage().
142 GLenum getCurrentTextureTarget() const;
144 // getCurrentCrop returns the cropping rectangle of the current buffer.
145 Rect getCurrentCrop() const;
147 // getCurrentTransform returns the transform of the current buffer.
148 uint32_t getCurrentTransform() const;
150 // getCurrentScalingMode returns the scaling mode of the current buffer.
151 uint32_t getCurrentScalingMode() const;
153 // getCurrentFence returns the fence indicating when the current buffer is
154 // ready to be read from.
155 sp<Fence> getCurrentFence() const;
157 // isSynchronousMode returns whether the SurfaceTexture is currently in
159 bool isSynchronousMode() const;
161 // set the name of the SurfaceTexture that will be used to identify it in
163 void setName(const String8& name);
165 // These functions call the corresponding BufferQueue implementation
166 // so the refactoring can proceed smoothly
167 status_t setDefaultBufferFormat(uint32_t defaultFormat);
168 status_t setConsumerUsageBits(uint32_t usage);
169 status_t setTransformHint(uint32_t hint);
170 virtual status_t setSynchronousMode(bool enabled);
172 // getBufferQueue returns the BufferQueue object to which this
173 // SurfaceTexture is connected.
174 sp<BufferQueue> getBufferQueue() const {
178 // detachFromContext detaches the SurfaceTexture from the calling thread's
179 // current OpenGL ES context. This context must be the same as the context
180 // that was current for previous calls to updateTexImage.
182 // Detaching a SurfaceTexture from an OpenGL ES context will result in the
183 // deletion of the OpenGL ES texture object into which the images were being
184 // streamed. After a SurfaceTexture has been detached from the OpenGL ES
185 // context calls to updateTexImage will fail returning INVALID_OPERATION
186 // until the SurfaceTexture is attached to a new OpenGL ES context using the
187 // attachToContext method.
188 status_t detachFromContext();
190 // attachToContext attaches a SurfaceTexture that is currently in the
191 // 'detached' state to the current OpenGL ES context. A SurfaceTexture is
192 // in the 'detached' state iff detachFromContext has successfully been
193 // called and no calls to attachToContext have succeeded since the last
194 // detachFromContext call. Calls to attachToContext made on a
195 // SurfaceTexture that is not in the 'detached' state will result in an
196 // INVALID_OPERATION error.
198 // The tex argument specifies the OpenGL ES texture object name in the
199 // new context into which the image contents will be streamed. A successful
200 // call to attachToContext will result in this texture object being bound to
201 // the texture target and populated with the image contents that were
202 // current at the time of the last call to detachFromContext.
203 status_t attachToContext(GLuint tex);
207 // abandonLocked overrides the ConsumerBase method to clear
208 // mCurrentTextureBuf in addition to the ConsumerBase behavior.
209 virtual void abandonLocked();
211 // dumpLocked overrides the ConsumerBase method to dump SurfaceTexture-
212 // specific info in addition to the ConsumerBase behavior.
213 virtual void dumpLocked(String8& result, const char* prefix, char* buffer,
216 // acquireBufferLocked overrides the ConsumerBase method to update the
217 // mEglSlots array in addition to the ConsumerBase behavior.
218 virtual status_t acquireBufferLocked(BufferQueue::BufferItem *item);
220 // releaseBufferLocked overrides the ConsumerBase method to update the
221 // mEglSlots array in addition to the ConsumerBase.
222 virtual status_t releaseBufferLocked(int buf, EGLDisplay display,
223 EGLSyncKHR eglFence, const sp<Fence>& fence);
225 static bool isExternalFormat(uint32_t format);
228 // this version of updateTexImage() takes a functor used to reject or not
229 // the newly acquired buffer.
230 // this API is TEMPORARY and intended to be used by SurfaceFlinger only,
231 // which is why class Layer is made a friend of SurfaceTexture below.
232 class BufferRejecter {
233 friend class SurfaceTexture;
234 virtual bool reject(const sp<GraphicBuffer>& buf,
235 const BufferQueue::BufferItem& item) = 0;
237 virtual ~BufferRejecter() { }
240 status_t updateTexImage(BufferRejecter* rejecter);
242 // createImage creates a new EGLImage from a GraphicBuffer.
243 EGLImageKHR createImage(EGLDisplay dpy,
244 const sp<GraphicBuffer>& graphicBuffer);
246 // freeBufferLocked frees up the given buffer slot. If the slot has been
247 // initialized this will release the reference to the GraphicBuffer in that
248 // slot and destroy the EGLImage in that slot. Otherwise it has no effect.
250 // This method must be called with mMutex locked.
251 virtual void freeBufferLocked(int slotIndex);
253 // computeCurrentTransformMatrix computes the transform matrix for the
254 // current texture. It uses mCurrentTransform and the current GraphicBuffer
255 // to compute this matrix and stores it in mCurrentTransformMatrix.
256 void computeCurrentTransformMatrix();
258 // syncForReleaseLocked performs the synchronization needed to release the
259 // current slot from an OpenGL ES context. If needed it will set the
260 // current slot's fence to guard against a producer accessing the buffer
261 // before the outstanding accesses have completed.
262 status_t syncForReleaseLocked(EGLDisplay dpy);
264 // The default consumer usage flags that SurfaceTexture always sets on its
265 // BufferQueue instance; these will be OR:d with any additional flags passed
266 // from the SurfaceTexture user. In particular, SurfaceTexture will always
267 // consume buffers as hardware textures.
268 static const uint32_t DEFAULT_USAGE_FLAGS = GraphicBuffer::USAGE_HW_TEXTURE;
270 // mCurrentTextureBuf is the graphic buffer of the current texture. It's
271 // possible that this buffer is not associated with any buffer slot, so we
272 // must track it separately in order to support the getCurrentBuffer method.
273 sp<GraphicBuffer> mCurrentTextureBuf;
275 // mCurrentCrop is the crop rectangle that applies to the current texture.
276 // It gets set each time updateTexImage is called.
279 // mCurrentTransform is the transform identifier for the current texture. It
280 // gets set each time updateTexImage is called.
281 uint32_t mCurrentTransform;
283 // mCurrentScalingMode is the scaling mode for the current texture. It gets
284 // set to each time updateTexImage is called.
285 uint32_t mCurrentScalingMode;
287 // mCurrentFence is the fence received from BufferQueue in updateTexImage.
288 sp<Fence> mCurrentFence;
290 // mCurrentTransformMatrix is the transform matrix for the current texture.
291 // It gets computed by computeTransformMatrix each time updateTexImage is
293 float mCurrentTransformMatrix[16];
295 // mCurrentTimestamp is the timestamp for the current texture. It
296 // gets set each time updateTexImage is called.
297 int64_t mCurrentTimestamp;
299 uint32_t mDefaultWidth, mDefaultHeight;
301 // mFilteringEnabled indicates whether the transform matrix is computed for
302 // use with bilinear filtering. It defaults to true and is changed by
303 // setFilteringEnabled().
304 bool mFilteringEnabled;
306 // mTexName is the name of the OpenGL texture to which streamed images will
307 // be bound when updateTexImage is called. It is set at construction time
308 // and can be changed with a call to attachToContext.
311 // mUseFenceSync indicates whether creation of the EGL_KHR_fence_sync
312 // extension should be used to prevent buffers from being dequeued before
313 // it's safe for them to be written. It gets set at construction time and
315 const bool mUseFenceSync;
317 // mTexTarget is the GL texture target with which the GL texture object is
318 // associated. It is set in the constructor and never changed. It is
319 // almost always GL_TEXTURE_EXTERNAL_OES except for one use case in Android
320 // Browser. In that case it is set to GL_TEXTURE_2D to allow
321 // glCopyTexSubImage to read from the texture. This is a hack to work
322 // around a GL driver limitation on the number of FBO attachments, which the
323 // browser's tile cache exceeds.
324 const GLenum mTexTarget;
326 // EGLSlot contains the information and object references that
327 // SurfaceTexture maintains about a BufferQueue buffer slot.
330 : mEglImage(EGL_NO_IMAGE_KHR),
331 mEglFence(EGL_NO_SYNC_KHR) {
334 // mEglImage is the EGLImage created from mGraphicBuffer.
335 EGLImageKHR mEglImage;
337 // mFence is the EGL sync object that must signal before the buffer
338 // associated with this buffer slot may be dequeued. It is initialized
339 // to EGL_NO_SYNC_KHR when the buffer is created and (optionally, based
340 // on a compile-time option) set to a new sync object in updateTexImage.
341 EGLSyncKHR mEglFence;
344 // mEglDisplay is the EGLDisplay with which this SurfaceTexture is currently
345 // associated. It is intialized to EGL_NO_DISPLAY and gets set to the
346 // current display when updateTexImage is called for the first time and when
347 // attachToContext is called.
348 EGLDisplay mEglDisplay;
350 // mEglContext is the OpenGL ES context with which this SurfaceTexture is
351 // currently associated. It is initialized to EGL_NO_CONTEXT and gets set
352 // to the current GL context when updateTexImage is called for the first
353 // time and when attachToContext is called.
354 EGLContext mEglContext;
356 // mEGLSlots stores the buffers that have been allocated by the BufferQueue
357 // for each buffer slot. It is initialized to null pointers, and gets
358 // filled in with the result of BufferQueue::acquire when the
359 // client dequeues a buffer from a
360 // slot that has not yet been used. The buffer allocated to a slot will also
361 // be replaced if the requested buffer usage or geometry differs from that
362 // of the buffer allocated to a slot.
363 EGLSlot mEglSlots[BufferQueue::NUM_BUFFER_SLOTS];
365 // mCurrentTexture is the buffer slot index of the buffer that is currently
366 // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
367 // indicating that no buffer slot is currently bound to the texture. Note,
368 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean
369 // that no buffer is bound to the texture. A call to setBufferCount will
370 // reset mCurrentTexture to INVALID_BUFFER_SLOT.
373 // mAttached indicates whether the ConsumerBase is currently attached to
374 // an OpenGL ES context. For legacy reasons, this is initialized to true,
375 // indicating that the ConsumerBase is considered to be attached to
376 // whatever context is current at the time of the first updateTexImage call.
377 // It is set to false by detachFromContext, and then set to true again by
382 // ----------------------------------------------------------------------------
383 }; // namespace android
385 #endif // ANDROID_GUI_SURFACETEXTURE_H