IGraphicBufferProducer.h revision 7cdd786fa80cf03551291ae8feca7b77583be1c5 
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 Surface;
36
37/*
38 * This class defines the Binder IPC interface for the producer side of
39 * a queue of graphics buffers.  It's used to send graphics data from one
40 * component to another.  For example, a class that decodes video for
41 * playback might use this to provide frames.  This is typically done
42 * indirectly, through Surface.
43 *
44 * The underlying mechanism is a BufferQueue, which implements
45 * BnGraphicBufferProducer.  In normal operation, the producer calls
46 * dequeueBuffer() to get an empty buffer, fills it with data, then
47 * calls queueBuffer() to make it available to the consumer.
48 *
49 * This class was previously called ISurfaceTexture.
50 */
51class IGraphicBufferProducer : public IInterface
52{
53public:
54    DECLARE_META_INTERFACE(GraphicBufferProducer);
55
56    enum {
57        BUFFER_NEEDS_REALLOCATION = 0x1,
58        RELEASE_ALL_BUFFERS       = 0x2,
59    };
60
61    // requestBuffer requests a new buffer for the given index. The server (i.e.
62    // the IGraphicBufferProducer implementation) assigns the newly created
63    // buffer to the given slot index, and the client is expected to mirror the
64    // slot->buffer mapping so that it's not necessary to transfer a
65    // GraphicBuffer for every dequeue operation.
66    virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf) = 0;
67
68    // setBufferCount sets the number of buffer slots available. Calling this
69    // will also cause all buffer slots to be emptied. The caller should empty
70    // its mirrored copy of the buffer slots when calling this method.
71    virtual status_t setBufferCount(int bufferCount) = 0;
72
73    // dequeueBuffer requests a new buffer slot for the client to use. Ownership
74    // of the slot is transfered to the client, meaning that the server will not
75    // use the contents of the buffer associated with that slot. The slot index
76    // returned may or may not contain a buffer. If the slot is empty the client
77    // should call requestBuffer to assign a new buffer to that slot. The client
78    // is expected to either call cancelBuffer on the dequeued slot or to fill
79    // in the contents of its associated buffer contents and call queueBuffer.
80    // If dequeueBuffer return BUFFER_NEEDS_REALLOCATION, the client is
81    // expected to call requestBuffer immediately.
82    //
83    // The fence parameter will be updated to hold the fence associated with
84    // the buffer. The contents of the buffer must not be overwritten until the
85    // fence signals. If the fence is NULL, the buffer may be written
86    // immediately.
87    //
88    // The async parameter sets whether we're in asynchrnous mode for this
89    // deququeBuffer() call.
90    virtual status_t dequeueBuffer(int *slot, sp<Fence>* fence, bool async,
91            uint32_t w, uint32_t h, uint32_t format, uint32_t usage) = 0;
92
93    // queueBuffer indicates that the client has finished filling in the
94    // contents of the buffer associated with slot and transfers ownership of
95    // that slot back to the server. It is not valid to call queueBuffer on a
96    // slot that is not owned by the client or one for which a buffer associated
97    // via requestBuffer. In addition, a timestamp must be provided by the
98    // client for this buffer. The timestamp is measured in nanoseconds, and
99    // must be monotonically increasing. Its other properties (zero point, etc)
100    // are client-dependent, and should be documented by the client.
101    //
102    // The async parameter sets whether we're queuing a buffer in asynchronous mode.
103    //
104    // outWidth, outHeight and outTransform are filled with the default width
105    // and height of the window and current transform applied to buffers,
106    // respectively.
107
108    struct QueueBufferInput : public Flattenable {
109        inline QueueBufferInput(const Parcel& parcel);
110        inline QueueBufferInput(int64_t timestamp,
111                const Rect& crop, int scalingMode, uint32_t transform, bool async,
112                const sp<Fence>& fence)
113        : timestamp(timestamp), crop(crop), scalingMode(scalingMode),
114          transform(transform), async(async), fence(fence) { }
115        inline void deflate(int64_t* outTimestamp, Rect* outCrop,
116                int* outScalingMode, uint32_t* outTransform, bool* outAsync,
117                sp<Fence>* outFence) const {
118            *outTimestamp = timestamp;
119            *outCrop = crop;
120            *outScalingMode = scalingMode;
121            *outTransform = transform;
122            *outAsync = bool(async);
123            *outFence = fence;
124        }
125
126        // Flattenable interface
127        virtual size_t getFlattenedSize() const;
128        virtual size_t getFdCount() const;
129        virtual status_t flatten(void* buffer, size_t size,
130                int fds[], size_t count) const;
131        virtual status_t unflatten(void const* buffer, size_t size,
132                int fds[], size_t count);
133
134    private:
135        int64_t timestamp;
136        Rect crop;
137        int scalingMode;
138        uint32_t transform;
139        int async;
140        sp<Fence> fence;
141    };
142
143    // QueueBufferOutput must be a POD structure
144    struct QueueBufferOutput {
145        inline QueueBufferOutput() { }
146        inline void deflate(uint32_t* outWidth,
147                uint32_t* outHeight,
148                uint32_t* outTransformHint,
149                uint32_t* outNumPendingBuffers) const {
150            *outWidth = width;
151            *outHeight = height;
152            *outTransformHint = transformHint;
153            *outNumPendingBuffers = numPendingBuffers;
154        }
155        inline void inflate(uint32_t inWidth, uint32_t inHeight,
156                uint32_t inTransformHint, uint32_t inNumPendingBuffers) {
157            width = inWidth;
158            height = inHeight;
159            transformHint = inTransformHint;
160            numPendingBuffers = inNumPendingBuffers;
161        }
162    private:
163        uint32_t width;
164        uint32_t height;
165        uint32_t transformHint;
166        uint32_t numPendingBuffers;
167    };
168
169    virtual status_t queueBuffer(int slot,
170            const QueueBufferInput& input, QueueBufferOutput* output) = 0;
171
172    // cancelBuffer indicates that the client does not wish to fill in the
173    // buffer associated with slot and transfers ownership of the slot back to
174    // the server.
175    virtual void cancelBuffer(int slot, const sp<Fence>& fence) = 0;
176
177    // query retrieves some information for this surface
178    // 'what' tokens allowed are that of android_natives.h
179    virtual int query(int what, int* value) = 0;
180
181    // connect attempts to connect a client API to the IGraphicBufferProducer.
182    // This must be called before any other IGraphicBufferProducer methods are
183    // called except for getAllocator.
184    //
185    // This method will fail if the connect was previously called on the
186    // IGraphicBufferProducer and no corresponding disconnect call was made.
187    //
188    // outWidth, outHeight and outTransform are filled with the default width
189    // and height of the window and current transform applied to buffers,
190    // respectively.
191    virtual status_t connect(int api, bool producerControlledByApp, QueueBufferOutput* output) = 0;
192
193    // disconnect attempts to disconnect a client API from the
194    // IGraphicBufferProducer.  Calling this method will cause any subsequent
195    // calls to other IGraphicBufferProducer methods to fail except for
196    // getAllocator and connect.  Successfully calling connect after this will
197    // allow the other methods to succeed again.
198    //
199    // This method will fail if the the IGraphicBufferProducer is not currently
200    // connected to the specified client API.
201    virtual status_t disconnect(int api) = 0;
202};
203
204// ----------------------------------------------------------------------------
205
206class BnGraphicBufferProducer : public BnInterface<IGraphicBufferProducer>
207{
208public:
209    virtual status_t    onTransact( uint32_t code,
210                                    const Parcel& data,
211                                    Parcel* reply,
212                                    uint32_t flags = 0);
213};
214
215// ----------------------------------------------------------------------------
216}; // namespace android
217
218#endif // ANDROID_GUI_IGRAPHICBUFFERPRODUCER_H
219