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_CONSUMER_H
18 #define ANDROID_GUI_CONSUMER_H
21 #include <EGL/eglext.h>
22 #include <GLES2/gl2.h>
23 #include <GLES2/gl2ext.h>
25 #include <gui/IGraphicBufferProducer.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"
36 #define ANDROID_GRAPHICS_FRAMEAVAILABLELISTENER_JNI_ID \
37 "mFrameAvailableListener"
40 // ----------------------------------------------------------------------------
46 * GLConsumer consumes buffers of graphics data from a BufferQueue,
47 * and makes them available to OpenGL as a texture.
49 * A typical usage pattern is to set up the GLConsumer with the
50 * desired options, and call updateTexImage() when a new frame is desired.
51 * If a new frame is available, the texture will be updated. If not,
52 * the previous contents are retained.
54 * By default, the texture is attached to the GL_TEXTURE_EXTERNAL_OES
55 * texture target, in the EGL context of the first thread that calls
58 * This class was previously called SurfaceTexture.
60 class GLConsumer : public ConsumerBase {
62 typedef ConsumerBase::FrameAvailableListener FrameAvailableListener;
64 // GLConsumer constructs a new GLConsumer object. tex indicates the
65 // name of the OpenGL ES texture to which images are to be streamed.
66 // allowSynchronousMode specifies whether or not synchronous mode can be
67 // enabled. texTarget specifies the OpenGL ES texture target to which the
68 // texture will be bound in updateTexImage. useFenceSync specifies whether
69 // fences should be used to synchronize access to buffers if that behavior
70 // is enabled at compile-time. A custom bufferQueue can be specified
71 // if behavior for queue/dequeue/connect etc needs to be customized.
72 // Otherwise a default BufferQueue will be created and used.
74 // For legacy reasons, the GLConsumer is created in a state where it is
75 // considered attached to an OpenGL ES context for the purposes of the
76 // attachToContext and detachFromContext methods. However, despite being
77 // considered "attached" to a context, the specific OpenGL ES context
78 // doesn't get latched until the first call to updateTexImage. After that
79 // point, all calls to updateTexImage must be made with the same OpenGL ES
82 // A GLConsumer may be detached from one OpenGL ES context and then
83 // attached to a different context using the detachFromContext and
84 // attachToContext methods, respectively. The intention of these methods is
85 // purely to allow a GLConsumer to be transferred from one consumer
86 // context to another. If such a transfer is not needed there is no
87 // requirement that either of these methods be called.
88 GLConsumer(GLuint tex, bool allowSynchronousMode = true,
89 GLenum texTarget = GL_TEXTURE_EXTERNAL_OES, bool useFenceSync = true,
90 const sp<BufferQueue> &bufferQueue = 0);
92 // updateTexImage acquires the most recently queued buffer, and sets the
93 // image contents of the target texture to it.
95 // This call may only be made while the OpenGL ES context to which the
96 // target texture belongs is bound to the calling thread.
98 // This calls doGLFenceWait to ensure proper synchronization.
99 status_t updateTexImage();
101 // setReleaseFence stores a fence that will signal when the current buffer
102 // is no longer being read. This fence will be returned to the producer
103 // when the current buffer is released by updateTexImage(). Multiple
104 // fences can be set for a given buffer; they will be merged into a single
106 void setReleaseFence(const sp<Fence>& fence);
108 // setDefaultMaxBufferCount sets the default limit on the maximum number
109 // of buffers that will be allocated at one time. The image producer may
110 // override the limit.
111 status_t setDefaultMaxBufferCount(int bufferCount);
113 // getTransformMatrix retrieves the 4x4 texture coordinate transform matrix
114 // associated with the texture image set by the most recent call to
117 // This transform matrix maps 2D homogeneous texture coordinates of the form
118 // (s, t, 0, 1) with s and t in the inclusive range [0, 1] to the texture
119 // coordinate that should be used to sample that location from the texture.
120 // Sampling the texture outside of the range of this transform is undefined.
122 // This transform is necessary to compensate for transforms that the stream
123 // content producer may implicitly apply to the content. By forcing users of
124 // a GLConsumer to apply this transform we avoid performing an extra
125 // copy of the data that would be needed to hide the transform from the
128 // The matrix is stored in column-major order so that it may be passed
129 // directly to OpenGL ES via the glLoadMatrixf or glUniformMatrix4fv
131 void getTransformMatrix(float mtx[16]);
133 // getTimestamp retrieves the timestamp associated with the texture image
134 // set by the most recent call to updateTexImage.
136 // The timestamp is in nanoseconds, and is monotonically increasing. Its
137 // other semantics (zero point, etc) are source-dependent and should be
138 // documented by the source.
139 int64_t getTimestamp();
141 // setDefaultBufferSize is used to set the size of buffers returned by
142 // requestBuffers when a with and height of zero is requested.
143 // A call to setDefaultBufferSize() may trigger requestBuffers() to
144 // be called from the client.
145 // The width and height parameters must be no greater than the minimum of
146 // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv).
147 // An error due to invalid dimensions might not be reported until
148 // updateTexImage() is called.
149 status_t setDefaultBufferSize(uint32_t width, uint32_t height);
151 // setFilteringEnabled sets whether the transform matrix should be computed
152 // for use with bilinear filtering.
153 void setFilteringEnabled(bool enabled);
155 // getCurrentBuffer returns the buffer associated with the current image.
156 sp<GraphicBuffer> getCurrentBuffer() const;
158 // getCurrentTextureTarget returns the texture target of the current
159 // texture as returned by updateTexImage().
160 GLenum getCurrentTextureTarget() const;
162 // getCurrentCrop returns the cropping rectangle of the current buffer.
163 Rect getCurrentCrop() const;
165 // getCurrentTransform returns the transform of the current buffer.
166 uint32_t getCurrentTransform() const;
168 // getCurrentScalingMode returns the scaling mode of the current buffer.
169 uint32_t getCurrentScalingMode() const;
171 // getCurrentFence returns the fence indicating when the current buffer is
172 // ready to be read from.
173 sp<Fence> getCurrentFence() const;
175 // doGLFenceWait inserts a wait command into the OpenGL ES command stream
176 // to ensure that it is safe for future OpenGL ES commands to access the
177 // current texture buffer.
178 status_t doGLFenceWait() const;
180 // isSynchronousMode returns whether the GLConsumer is currently in
182 bool isSynchronousMode() const;
184 // set the name of the GLConsumer that will be used to identify it in
186 void setName(const String8& name);
188 // These functions call the corresponding BufferQueue implementation
189 // so the refactoring can proceed smoothly
190 status_t setDefaultBufferFormat(uint32_t defaultFormat);
191 status_t setConsumerUsageBits(uint32_t usage);
192 status_t setTransformHint(uint32_t hint);
193 virtual status_t setSynchronousMode(bool enabled);
195 // getBufferQueue returns the BufferQueue object to which this
196 // GLConsumer is connected.
197 sp<BufferQueue> getBufferQueue() const {
201 // detachFromContext detaches the GLConsumer from the calling thread's
202 // current OpenGL ES context. This context must be the same as the context
203 // that was current for previous calls to updateTexImage.
205 // Detaching a GLConsumer from an OpenGL ES context will result in the
206 // deletion of the OpenGL ES texture object into which the images were being
207 // streamed. After a GLConsumer has been detached from the OpenGL ES
208 // context calls to updateTexImage will fail returning INVALID_OPERATION
209 // until the GLConsumer is attached to a new OpenGL ES context using the
210 // attachToContext method.
211 status_t detachFromContext();
213 // attachToContext attaches a GLConsumer that is currently in the
214 // 'detached' state to the current OpenGL ES context. A GLConsumer is
215 // in the 'detached' state iff detachFromContext has successfully been
216 // called and no calls to attachToContext have succeeded since the last
217 // detachFromContext call. Calls to attachToContext made on a
218 // GLConsumer that is not in the 'detached' state will result in an
219 // INVALID_OPERATION error.
221 // The tex argument specifies the OpenGL ES texture object name in the
222 // new context into which the image contents will be streamed. A successful
223 // call to attachToContext will result in this texture object being bound to
224 // the texture target and populated with the image contents that were
225 // current at the time of the last call to detachFromContext.
226 status_t attachToContext(GLuint tex);
230 // abandonLocked overrides the ConsumerBase method to clear
231 // mCurrentTextureBuf in addition to the ConsumerBase behavior.
232 virtual void abandonLocked();
234 // dumpLocked overrides the ConsumerBase method to dump GLConsumer-
235 // specific info in addition to the ConsumerBase behavior.
236 virtual void dumpLocked(String8& result, const char* prefix, char* buffer,
239 // acquireBufferLocked overrides the ConsumerBase method to update the
240 // mEglSlots array in addition to the ConsumerBase behavior.
241 virtual status_t acquireBufferLocked(BufferQueue::BufferItem *item);
243 // releaseBufferLocked overrides the ConsumerBase method to update the
244 // mEglSlots array in addition to the ConsumerBase.
245 virtual status_t releaseBufferLocked(int buf, EGLDisplay display,
246 EGLSyncKHR eglFence);
248 status_t releaseBufferLocked(int buf, EGLSyncKHR eglFence) {
249 return releaseBufferLocked(buf, mEglDisplay, eglFence);
252 static bool isExternalFormat(uint32_t format);
254 // This releases the buffer in the slot referenced by mCurrentTexture,
255 // then updates state to refer to the BufferItem, which must be a
256 // newly-acquired buffer.
257 status_t releaseAndUpdateLocked(const BufferQueue::BufferItem& item);
259 // Binds mTexName and the current buffer to mTexTarget. Uses
260 // mCurrentTexture if it's set, mCurrentTextureBuf if not. If the
261 // bind succeeds, this calls doGLFenceWait.
262 status_t bindTextureImageLocked();
264 // Gets the current EGLDisplay and EGLContext values, and compares them
265 // to mEglDisplay and mEglContext. If the fields have been previously
266 // set, the values must match; if not, the fields are set to the current
268 status_t checkAndUpdateEglStateLocked();
270 // If set, GLConsumer will use the EGL_ANDROID_native_fence_sync
271 // extension to create Android native fences for GLES activity.
272 static const bool sUseNativeFenceSync;
275 // createImage creates a new EGLImage from a GraphicBuffer.
276 EGLImageKHR createImage(EGLDisplay dpy,
277 const sp<GraphicBuffer>& graphicBuffer);
279 // freeBufferLocked frees up the given buffer slot. If the slot has been
280 // initialized this will release the reference to the GraphicBuffer in that
281 // slot and destroy the EGLImage in that slot. Otherwise it has no effect.
283 // This method must be called with mMutex locked.
284 virtual void freeBufferLocked(int slotIndex);
286 // computeCurrentTransformMatrixLocked computes the transform matrix for the
287 // current texture. It uses mCurrentTransform and the current GraphicBuffer
288 // to compute this matrix and stores it in mCurrentTransformMatrix.
289 // mCurrentTextureBuf must not be NULL.
290 void computeCurrentTransformMatrixLocked();
292 // doGLFenceWaitLocked inserts a wait command into the OpenGL ES command
293 // stream to ensure that it is safe for future OpenGL ES commands to
294 // access the current texture buffer.
295 status_t doGLFenceWaitLocked() const;
297 // syncForReleaseLocked performs the synchronization needed to release the
298 // current slot from an OpenGL ES context. If needed it will set the
299 // current slot's fence to guard against a producer accessing the buffer
300 // before the outstanding accesses have completed.
301 status_t syncForReleaseLocked(EGLDisplay dpy);
303 // Normally, when we bind a buffer to a texture target, we bind a buffer
304 // that is referenced by an entry in mEglSlots. In some situations we
305 // have a buffer in mCurrentTextureBuf, but no corresponding entry for
306 // it in our slot array. bindUnslottedBuffer handles that situation by
307 // binding the buffer without touching the EglSlots.
308 status_t bindUnslottedBufferLocked(EGLDisplay dpy);
310 // The default consumer usage flags that GLConsumer always sets on its
311 // BufferQueue instance; these will be OR:d with any additional flags passed
312 // from the GLConsumer user. In particular, GLConsumer will always
313 // consume buffers as hardware textures.
314 static const uint32_t DEFAULT_USAGE_FLAGS = GraphicBuffer::USAGE_HW_TEXTURE;
316 // mCurrentTextureBuf is the graphic buffer of the current texture. It's
317 // possible that this buffer is not associated with any buffer slot, so we
318 // must track it separately in order to support the getCurrentBuffer method.
319 sp<GraphicBuffer> mCurrentTextureBuf;
321 // mCurrentCrop is the crop rectangle that applies to the current texture.
322 // It gets set each time updateTexImage is called.
325 // mCurrentTransform is the transform identifier for the current texture. It
326 // gets set each time updateTexImage is called.
327 uint32_t mCurrentTransform;
329 // mCurrentScalingMode is the scaling mode for the current texture. It gets
330 // set to each time updateTexImage is called.
331 uint32_t mCurrentScalingMode;
333 // mCurrentFence is the fence received from BufferQueue in updateTexImage.
334 sp<Fence> mCurrentFence;
336 // mCurrentTransformMatrix is the transform matrix for the current texture.
337 // It gets computed by computeTransformMatrix each time updateTexImage is
339 float mCurrentTransformMatrix[16];
341 // mCurrentTimestamp is the timestamp for the current texture. It
342 // gets set each time updateTexImage is called.
343 int64_t mCurrentTimestamp;
345 uint32_t mDefaultWidth, mDefaultHeight;
347 // mFilteringEnabled indicates whether the transform matrix is computed for
348 // use with bilinear filtering. It defaults to true and is changed by
349 // setFilteringEnabled().
350 bool mFilteringEnabled;
352 // mTexName is the name of the OpenGL texture to which streamed images will
353 // be bound when updateTexImage is called. It is set at construction time
354 // and can be changed with a call to attachToContext.
357 // mUseFenceSync indicates whether creation of the EGL_KHR_fence_sync
358 // extension should be used to prevent buffers from being dequeued before
359 // it's safe for them to be written. It gets set at construction time and
361 const bool mUseFenceSync;
363 // mTexTarget is the GL texture target with which the GL texture object is
364 // associated. It is set in the constructor and never changed. It is
365 // almost always GL_TEXTURE_EXTERNAL_OES except for one use case in Android
366 // Browser. In that case it is set to GL_TEXTURE_2D to allow
367 // glCopyTexSubImage to read from the texture. This is a hack to work
368 // around a GL driver limitation on the number of FBO attachments, which the
369 // browser's tile cache exceeds.
370 const GLenum mTexTarget;
372 // EGLSlot contains the information and object references that
373 // GLConsumer maintains about a BufferQueue buffer slot.
376 : mEglImage(EGL_NO_IMAGE_KHR),
377 mEglFence(EGL_NO_SYNC_KHR) {
380 // mEglImage is the EGLImage created from mGraphicBuffer.
381 EGLImageKHR mEglImage;
383 // mFence is the EGL sync object that must signal before the buffer
384 // associated with this buffer slot may be dequeued. It is initialized
385 // to EGL_NO_SYNC_KHR when the buffer is created and (optionally, based
386 // on a compile-time option) set to a new sync object in updateTexImage.
387 EGLSyncKHR mEglFence;
390 // mEglDisplay is the EGLDisplay with which this GLConsumer is currently
391 // associated. It is intialized to EGL_NO_DISPLAY and gets set to the
392 // current display when updateTexImage is called for the first time and when
393 // attachToContext is called.
394 EGLDisplay mEglDisplay;
396 // mEglContext is the OpenGL ES context with which this GLConsumer is
397 // currently associated. It is initialized to EGL_NO_CONTEXT and gets set
398 // to the current GL context when updateTexImage is called for the first
399 // time and when attachToContext is called.
400 EGLContext mEglContext;
402 // mEGLSlots stores the buffers that have been allocated by the BufferQueue
403 // for each buffer slot. It is initialized to null pointers, and gets
404 // filled in with the result of BufferQueue::acquire when the
405 // client dequeues a buffer from a
406 // slot that has not yet been used. The buffer allocated to a slot will also
407 // be replaced if the requested buffer usage or geometry differs from that
408 // of the buffer allocated to a slot.
409 EglSlot mEglSlots[BufferQueue::NUM_BUFFER_SLOTS];
411 // mCurrentTexture is the buffer slot index of the buffer that is currently
412 // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
413 // indicating that no buffer slot is currently bound to the texture. Note,
414 // however, that a value of INVALID_BUFFER_SLOT does not necessarily mean
415 // that no buffer is bound to the texture. A call to setBufferCount will
416 // reset mCurrentTexture to INVALID_BUFFER_SLOT.
419 // mAttached indicates whether the ConsumerBase is currently attached to
420 // an OpenGL ES context. For legacy reasons, this is initialized to true,
421 // indicating that the ConsumerBase is considered to be attached to
422 // whatever context is current at the time of the first updateTexImage call.
423 // It is set to false by detachFromContext, and then set to true again by
428 // ----------------------------------------------------------------------------
429 }; // namespace android
431 #endif // ANDROID_GUI_CONSUMER_H