IGraphicBufferProducer.h revision 595264f1af12e25dce57d7c5b1d52ed86ac0d0c9 
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    virtual status_t dequeueBuffer(int *slot, sp<Fence>* fence,
88            uint32_t w, uint32_t h, uint32_t format, uint32_t usage) = 0;
89
90    // queueBuffer indicates that the client has finished filling in the
91    // contents of the buffer associated with slot and transfers ownership of
92    // that slot back to the server. It is not valid to call queueBuffer on a
93    // slot that is not owned by the client or one for which a buffer associated
94    // via requestBuffer. In addition, a timestamp must be provided by the
95    // client for this buffer. The timestamp is measured in nanoseconds, and
96    // must be monotonically increasing. Its other properties (zero point, etc)
97    // are client-dependent, and should be documented by the client.
98    //
99    // outWidth, outHeight and outTransform are filled with the default width
100    // and height of the window and current transform applied to buffers,
101    // respectively.
102
103    struct QueueBufferInput : public Flattenable {
104        inline QueueBufferInput(const Parcel& parcel);
105        inline QueueBufferInput(int64_t timestamp,
106                const Rect& crop, int scalingMode, uint32_t transform,
107                sp<Fence> fence)
108        : timestamp(timestamp), crop(crop), scalingMode(scalingMode),
109          transform(transform), fence(fence) { }
110        inline void deflate(int64_t* outTimestamp, Rect* outCrop,
111                int* outScalingMode, uint32_t* outTransform,
112                sp<Fence>* outFence) const {
113            *outTimestamp = timestamp;
114            *outCrop = crop;
115            *outScalingMode = scalingMode;
116            *outTransform = transform;
117            *outFence = fence;
118        }
119
120        // Flattenable interface
121        virtual size_t getFlattenedSize() const;
122        virtual size_t getFdCount() const;
123        virtual status_t flatten(void* buffer, size_t size,
124                int fds[], size_t count) const;
125        virtual status_t unflatten(void const* buffer, size_t size,
126                int fds[], size_t count);
127
128    private:
129        int64_t timestamp;
130        Rect crop;
131        int scalingMode;
132        uint32_t transform;
133        sp<Fence> fence;
134    };
135
136    // QueueBufferOutput must be a POD structure
137    struct QueueBufferOutput {
138        inline QueueBufferOutput() { }
139        inline void deflate(uint32_t* outWidth,
140                uint32_t* outHeight,
141                uint32_t* outTransformHint,
142                uint32_t* outNumPendingBuffers) const {
143            *outWidth = width;
144            *outHeight = height;
145            *outTransformHint = transformHint;
146            *outNumPendingBuffers = numPendingBuffers;
147        }
148        inline void inflate(uint32_t inWidth, uint32_t inHeight,
149                uint32_t inTransformHint, uint32_t inNumPendingBuffers) {
150            width = inWidth;
151            height = inHeight;
152            transformHint = inTransformHint;
153            numPendingBuffers = inNumPendingBuffers;
154        }
155    private:
156        uint32_t width;
157        uint32_t height;
158        uint32_t transformHint;
159        uint32_t numPendingBuffers;
160    };
161
162    virtual status_t queueBuffer(int slot,
163            const QueueBufferInput& input, QueueBufferOutput* output) = 0;
164
165    // cancelBuffer indicates that the client does not wish to fill in the
166    // buffer associated with slot and transfers ownership of the slot back to
167    // the server.
168    virtual void cancelBuffer(int slot, const sp<Fence>& fence) = 0;
169
170    // query retrieves some information for this surface
171    // 'what' tokens allowed are that of android_natives.h
172    virtual int query(int what, int* value) = 0;
173
174    // connect attempts to connect a client API to the IGraphicBufferProducer.
175    // This must be called before any other IGraphicBufferProducer methods are
176    // called except for getAllocator.
177    //
178    // This method will fail if the connect was previously called on the
179    // IGraphicBufferProducer and no corresponding disconnect call was made.
180    //
181    // outWidth, outHeight and outTransform are filled with the default width
182    // and height of the window and current transform applied to buffers,
183    // respectively.
184    virtual status_t connect(int api, bool producerControlledByApp, QueueBufferOutput* output) = 0;
185
186    // disconnect attempts to disconnect a client API from the
187    // IGraphicBufferProducer.  Calling this method will cause any subsequent
188    // calls to other IGraphicBufferProducer methods to fail except for
189    // getAllocator and connect.  Successfully calling connect after this will
190    // allow the other methods to succeed again.
191    //
192    // This method will fail if the the IGraphicBufferProducer is not currently
193    // connected to the specified client API.
194    virtual status_t disconnect(int api) = 0;
195};
196
197// ----------------------------------------------------------------------------
198
199class BnGraphicBufferProducer : public BnInterface<IGraphicBufferProducer>
200{
201public:
202    virtual status_t    onTransact( uint32_t code,
203                                    const Parcel& data,
204                                    Parcel* reply,
205                                    uint32_t flags = 0);
206};
207
208// ----------------------------------------------------------------------------
209}; // namespace android
210
211#endif // ANDROID_GUI_IGRAPHICBUFFERPRODUCER_H
212