RenderThread.h revision ba6adf66d3c44c0aa2fd8a224862ff1901d64300 
1/*
2 * Copyright (C) 2013 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 RENDERTHREAD_H_
18#define RENDERTHREAD_H_
19
20#include "RenderTask.h"
21
22#include "../JankTracker.h"
23#include "TimeLord.h"
24
25#include <cutils/compiler.h>
26#include <utils/Looper.h>
27#include <utils/Mutex.h>
28#include <utils/Singleton.h>
29#include <utils/Thread.h>
30
31#include <memory>
32#include <set>
33
34namespace android {
35
36class DisplayEventReceiver;
37
38namespace uirenderer {
39
40class RenderState;
41
42namespace renderthread {
43
44class CanvasContext;
45class DispatchFrameCallbacks;
46class EglManager;
47class RenderProxy;
48
49class TaskQueue {
50public:
51    TaskQueue();
52
53    RenderTask* next();
54    void queue(RenderTask* task);
55    void queueAtFront(RenderTask* task);
56    RenderTask* peek();
57    void remove(RenderTask* task);
58
59private:
60    RenderTask* mHead;
61    RenderTask* mTail;
62};
63
64// Mimics android.view.Choreographer.FrameCallback
65class IFrameCallback {
66public:
67    virtual void doFrame() = 0;
68
69protected:
70    ~IFrameCallback() {}
71};
72
73class ANDROID_API RenderThread : public Thread, protected Singleton<RenderThread> {
74public:
75    // RenderThread takes complete ownership of tasks that are queued
76    // and will delete them after they are run
77    ANDROID_API void queue(RenderTask* task);
78    ANDROID_API void queueAtFront(RenderTask* task);
79    void queueAt(RenderTask* task, nsecs_t runAtNs);
80    void remove(RenderTask* task);
81
82    // Mimics android.view.Choreographer
83    void postFrameCallback(IFrameCallback* callback);
84    bool removeFrameCallback(IFrameCallback* callback);
85    // If the callback is currently registered, it will be pushed back until
86    // the next vsync. If it is not currently registered this does nothing.
87    void pushBackFrameCallback(IFrameCallback* callback);
88
89    void setFrameInterval(nsecs_t frameInterval);
90
91    TimeLord& timeLord() { return mTimeLord; }
92    RenderState& renderState() { return *mRenderState; }
93    EglManager& eglManager() { return *mEglManager; }
94    JankTracker& jankTracker() { return *mJankTracker; }
95
96protected:
97    virtual bool threadLoop() override;
98
99private:
100    friend class Singleton<RenderThread>;
101    friend class DispatchFrameCallbacks;
102    friend class RenderProxy;
103
104    RenderThread();
105    virtual ~RenderThread();
106
107    void initThreadLocals();
108    void initializeDisplayEventReceiver();
109    static int displayEventReceiverCallback(int fd, int events, void* data);
110    void drainDisplayEventQueue();
111    void dispatchFrameCallbacks();
112    void requestVsync();
113
114    // Returns the next task to be run. If this returns NULL nextWakeup is set
115    // to the time to requery for the nextTask to run. mNextWakeup is also
116    // set to this time
117    RenderTask* nextTask(nsecs_t* nextWakeup);
118
119    sp<Looper> mLooper;
120    Mutex mLock;
121
122    nsecs_t mNextWakeup;
123    TaskQueue mQueue;
124
125    DisplayEventReceiver* mDisplayEventReceiver;
126    bool mVsyncRequested;
127    std::set<IFrameCallback*> mFrameCallbacks;
128    // We defer the actual registration of these callbacks until
129    // both mQueue *and* mDisplayEventReceiver have been drained off all
130    // immediate events. This makes sure that we catch the next vsync, not
131    // the previous one
132    std::set<IFrameCallback*> mPendingRegistrationFrameCallbacks;
133    bool mFrameCallbackTaskPending;
134    DispatchFrameCallbacks* mFrameCallbackTask;
135
136    TimeLord mTimeLord;
137    RenderState* mRenderState;
138    EglManager* mEglManager;
139
140    JankTracker* mJankTracker = nullptr;
141};
142
143} /* namespace renderthread */
144} /* namespace uirenderer */
145} /* namespace android */
146#endif /* RENDERTHREAD_H_ */
147