IGraphicBufferProducer.h revision 2adaf04fab35cf47c824d74d901b54094e01ccd3 
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_IGRAPHICBUFFERPRODUCER_H
18#define ANDROID_GUI_IGRAPHICBUFFERPRODUCER_H
19
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <utils/Errors.h>
24#include <utils/RefBase.h>
25
26#include <binder/IInterface.h>
27
28#include <ui/Fence.h>
29#include <ui/GraphicBuffer.h>
30#include <ui/Rect.h>
31
32namespace android {
33// ----------------------------------------------------------------------------
34
35class SurfaceTextureClient;
36
37/*
38 * This class defines an interface that is implemented by classes that
39 * produce buffers of graphics data.  For example, a class that decodes
40 * video for playback might use this to provide frames.  This is
41 * typically done indirectly, through SurfaceTextureClient.
42 *
43 * The underlying mechanism is a BufferQueue.  In normal operation, the
44 * producer calls dequeueBuffer() to get an empty buffer, fills it with
45 * data, then calls queueBuffer() to make it available to the consumer.
46 *
47 * The BnGraphicBufferProducer and BpGraphicBufferProducer classes provide
48 * the Binder IPC implementation.
49 *
50 * This class was previously called ISurfaceTexture.
51 */
52class IGraphicBufferProducer : public IInterface
53{
54public:
55    DECLARE_META_INTERFACE(GraphicBufferProducer);
56
57    enum {
58        BUFFER_NEEDS_REALLOCATION = 0x1,
59        RELEASE_ALL_BUFFERS       = 0x2,
60    };
61
62    // requestBuffer requests a new buffer for the given index. The server (i.e.
63    // the IGraphicBufferProducer implementation) assigns the newly created
64    // buffer to the given slot index, and the client is expected to mirror the
65    // slot->buffer mapping so that it's not necessary to transfer a
66    // GraphicBuffer for every dequeue operation.
67    virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf) = 0;
68
69    // setBufferCount sets the number of buffer slots available. Calling this
70    // will also cause all buffer slots to be emptied. The caller should empty
71    // its mirrored copy of the buffer slots when calling this method.
72    virtual status_t setBufferCount(int bufferCount) = 0;
73
74    // dequeueBuffer requests a new buffer slot for the client to use. Ownership
75    // of the slot is transfered to the client, meaning that the server will not
76    // use the contents of the buffer associated with that slot. The slot index
77    // returned may or may not contain a buffer. If the slot is empty the client
78    // should call requestBuffer to assign a new buffer to that slot. The client
79    // is expected to either call cancelBuffer on the dequeued slot or to fill
80    // in the contents of its associated buffer contents and call queueBuffer.
81    // If dequeueBuffer return BUFFER_NEEDS_REALLOCATION, the client is
82    // expected to call requestBuffer immediately.
83    //
84    // The fence parameter will be updated to hold the fence associated with
85    // the buffer. The contents of the buffer must not be overwritten until the
86    // fence signals. If the fence is NULL, the buffer may be written
87    // immediately.
88    virtual status_t dequeueBuffer(int *slot, sp<Fence>& fence,
89            uint32_t w, uint32_t h, uint32_t format, uint32_t usage) = 0;
90
91    // queueBuffer indicates that the client has finished filling in the
92    // contents of the buffer associated with slot and transfers ownership of
93    // that slot back to the server. It is not valid to call queueBuffer on a
94    // slot that is not owned by the client or one for which a buffer associated
95    // via requestBuffer. In addition, a timestamp must be provided by the
96    // client for this buffer. The timestamp is measured in nanoseconds, and
97    // must be monotonically increasing. Its other properties (zero point, etc)
98    // are client-dependent, and should be documented by the client.
99    //
100    // outWidth, outHeight and outTransform are filled with the default width
101    // and height of the window and current transform applied to buffers,
102    // respectively.
103
104    struct QueueBufferInput : public Flattenable {
105        inline QueueBufferInput(const Parcel& parcel);
106        inline QueueBufferInput(int64_t timestamp,
107                const Rect& crop, int scalingMode, uint32_t transform,
108                sp<Fence> fence)
109        : timestamp(timestamp), crop(crop), scalingMode(scalingMode),
110          transform(transform), fence(fence) { }
111        inline void deflate(int64_t* outTimestamp, Rect* outCrop,
112                int* outScalingMode, uint32_t* outTransform,
113                sp<Fence>* outFence) const {
114            *outTimestamp = timestamp;
115            *outCrop = crop;
116            *outScalingMode = scalingMode;
117            *outTransform = transform;
118            *outFence = fence;
119        }
120
121        // Flattenable interface
122        virtual size_t getFlattenedSize() const;
123        virtual size_t getFdCount() const;
124        virtual status_t flatten(void* buffer, size_t size,
125                int fds[], size_t count) const;
126        virtual status_t unflatten(void const* buffer, size_t size,
127                int fds[], size_t count);
128
129    private:
130        int64_t timestamp;
131        Rect crop;
132        int scalingMode;
133        uint32_t transform;
134        sp<Fence> fence;
135    };
136
137    // QueueBufferOutput must be a POD structure
138    struct QueueBufferOutput {
139        inline QueueBufferOutput() { }
140        inline void deflate(uint32_t* outWidth,
141                uint32_t* outHeight,
142                uint32_t* outTransformHint,
143                uint32_t* outNumPendingBuffers) const {
144            *outWidth = width;
145            *outHeight = height;
146            *outTransformHint = transformHint;
147            *outNumPendingBuffers = numPendingBuffers;
148        }
149        inline void inflate(uint32_t inWidth, uint32_t inHeight,
150                uint32_t inTransformHint, uint32_t inNumPendingBuffers) {
151            width = inWidth;
152            height = inHeight;
153            transformHint = inTransformHint;
154            numPendingBuffers = inNumPendingBuffers;
155        }
156    private:
157        uint32_t width;
158        uint32_t height;
159        uint32_t transformHint;
160        uint32_t numPendingBuffers;
161    };
162
163    virtual status_t queueBuffer(int slot,
164            const QueueBufferInput& input, QueueBufferOutput* output) = 0;
165
166    // cancelBuffer indicates that the client does not wish to fill in the
167    // buffer associated with slot and transfers ownership of the slot back to
168    // the server.
169    virtual void cancelBuffer(int slot, sp<Fence> fence) = 0;
170
171    // query retrieves some information for this surface
172    // 'what' tokens allowed are that of android_natives.h
173    virtual int query(int what, int* value) = 0;
174
175    // setSynchronousMode set whether dequeueBuffer is synchronous or
176    // asynchronous. In synchronous mode, dequeueBuffer blocks until
177    // a buffer is available, the currently bound buffer can be dequeued and
178    // queued buffers will be retired in order.
179    // The default mode is asynchronous.
180    virtual status_t setSynchronousMode(bool enabled) = 0;
181
182    // connect attempts to connect a client API to the IGraphicBufferProducer.
183    // This must be called before any other IGraphicBufferProducer methods are
184    // called except for getAllocator.
185    //
186    // This method will fail if the connect was previously called on the
187    // IGraphicBufferProducer and no corresponding disconnect call was made.
188    //
189    // outWidth, outHeight and outTransform are filled with the default width
190    // and height of the window and current transform applied to buffers,
191    // respectively.
192    virtual status_t connect(int api, QueueBufferOutput* output) = 0;
193
194    // disconnect attempts to disconnect a client API from the
195    // IGraphicBufferProducer.  Calling this method will cause any subsequent
196    // calls to other IGraphicBufferProducer methods to fail except for
197    // getAllocator and connect.  Successfully calling connect after this will
198    // allow the other methods to succeed again.
199    //
200    // This method will fail if the the IGraphicBufferProducer is not currently
201    // connected to the specified client API.
202    virtual status_t disconnect(int api) = 0;
203};
204
205// ----------------------------------------------------------------------------
206
207class BnGraphicBufferProducer : public BnInterface<IGraphicBufferProducer>
208{
209public:
210    virtual status_t    onTransact( uint32_t code,
211                                    const Parcel& data,
212                                    Parcel* reply,
213                                    uint32_t flags = 0);
214};
215
216// ----------------------------------------------------------------------------
217}; // namespace android
218
219#endif // ANDROID_GUI_IGRAPHICBUFFERPRODUCER_H
220