1 /*
2  * Copyright 2014 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_BUFFERITEM_H
18 #define ANDROID_GUI_BUFFERITEM_H
19 
20 #include <ui/FenceTime.h>
21 #include <ui/Rect.h>
22 #include <ui/Region.h>
23 
24 #include <system/graphics.h>
25 
26 #include <utils/Flattenable.h>
27 #include <utils/StrongPointer.h>
28 
29 namespace android {
30 
31 class Fence;
32 class GraphicBuffer;
33 
34 class BufferItem : public Flattenable<BufferItem> {
35     friend class Flattenable<BufferItem>;
36     size_t getPodSize() const;
37     size_t getFlattenedSize() const;
38     size_t getFdCount() const;
39     status_t flatten(void*& buffer, size_t& size, int*& fds, size_t& count) const;
40     status_t unflatten(void const*& buffer, size_t& size, int const*& fds, size_t& count);
41 
42     public:
43     // The default value of mBuf, used to indicate this doesn't correspond to a slot.
44     enum { INVALID_BUFFER_SLOT = -1 };
45     BufferItem();
46     ~BufferItem();
47     BufferItem(const BufferItem&) = default;
48     BufferItem& operator=(const BufferItem&) = default;
49 
50     static const char* scalingModeName(uint32_t scalingMode);
51 
52     // mGraphicBuffer points to the buffer allocated for this slot, or is NULL
53     // if the buffer in this slot has been acquired in the past (see
54     // BufferSlot.mAcquireCalled).
55     sp<GraphicBuffer> mGraphicBuffer;
56 
57     // mFence is a fence that will signal when the buffer is idle.
58     sp<Fence> mFence;
59 
60     // The std::shared_ptr<FenceTime> wrapper around mFence.
61     std::shared_ptr<FenceTime> mFenceTime{FenceTime::NO_FENCE};
62 
63     // mCrop is the current crop rectangle for this buffer slot.
64     Rect mCrop;
65 
66     // mTransform is the current transform flags for this buffer slot.
67     // refer to NATIVE_WINDOW_TRANSFORM_* in <window.h>
68     uint32_t mTransform;
69 
70     // mScalingMode is the current scaling mode for this buffer slot.
71     // refer to NATIVE_WINDOW_SCALING_* in <window.h>
72     uint32_t mScalingMode;
73 
74     // mTimestamp is the current timestamp for this buffer slot. This gets
75     // to set by queueBuffer each time this slot is queued. This value
76     // is guaranteed to be monotonically increasing for each newly
77     // acquired buffer.
78     int64_t mTimestamp;
79 
80     // mIsAutoTimestamp indicates whether mTimestamp was generated
81     // automatically when the buffer was queued.
82     bool mIsAutoTimestamp;
83 
84     // mDataSpace is the current dataSpace value for this buffer slot. This gets
85     // set by queueBuffer each time this slot is queued. The meaning of the
86     // dataSpace is format-dependent.
87     android_dataspace mDataSpace;
88 
89     // mFrameNumber is the number of the queued frame for this slot.
90     uint64_t mFrameNumber;
91 
92     // mSlot is the slot index of this buffer (default INVALID_BUFFER_SLOT).
93     int mSlot;
94 
95     // mIsDroppable whether this buffer was queued with the
96     // property that it can be replaced by a new buffer for the purpose of
97     // making sure dequeueBuffer() won't block.
98     // i.e.: was the BufferQueue in "mDequeueBufferCannotBlock" when this buffer
99     // was queued.
100     bool mIsDroppable;
101 
102     // Indicates whether this buffer has been seen by a consumer yet
103     bool mAcquireCalled;
104 
105     // Indicates this buffer must be transformed by the inverse transform of the screen
106     // it is displayed onto. This is applied after mTransform.
107     bool mTransformToDisplayInverse;
108 
109     // Describes the portion of the surface that has been modified since the
110     // previous frame
111     Region mSurfaceDamage;
112 
113     // Indicates that the consumer should acquire the next frame as soon as it
114     // can and not wait for a frame to become available. This is only relevant
115     // in shared buffer mode.
116     bool mAutoRefresh;
117 
118     // Indicates that this buffer was queued by the producer. When in shared
119     // buffer mode acquire() can return a BufferItem that wasn't in the queue.
120     bool mQueuedBuffer;
121 
122     // Indicates that this BufferItem contains a stale buffer which has already
123     // been released by the BufferQueue.
124     bool mIsStale;
125 };
126 
127 } // namespace android
128 
129 #endif
130