1 /*
2  * Copyright (C) 2015 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 /**
18  * @addtogroup Choreographer
19  * @{
20  */
21 
22 /**
23  * @file choreographer.h
24  */
25 
26 #ifndef ANDROID_CHOREOGRAPHER_H
27 #define ANDROID_CHOREOGRAPHER_H
28 
29 #include <sys/cdefs.h>
30 
31 __BEGIN_DECLS
32 
33 struct AChoreographer;
34 typedef struct AChoreographer AChoreographer;
35 
36 /**
37  * Prototype of the function that is called when a new frame is being rendered.
38  * It's passed the time that the frame is being rendered as nanoseconds in the
39  * CLOCK_MONOTONIC time base, as well as the data pointer provided by the
40  * application that registered a callback. All callbacks that run as part of
41  * rendering a frame will observe the same frame time, so it should be used
42  * whenever events need to be synchronized (e.g. animations).
43  */
44 typedef void (*AChoreographer_frameCallback)(long frameTimeNanos, void* data);
45 
46 /**
47  * Get the AChoreographer instance for the current thread. This must be called
48  * on an ALooper thread.
49  */
50 AChoreographer* AChoreographer_getInstance();
51 
52 /**
53  * Post a callback to be run on the next frame. The data pointer provided will
54  * be passed to the callback function when it's called.
55  */
56 void AChoreographer_postFrameCallback(AChoreographer* choreographer,
57                 AChoreographer_frameCallback callback, void* data);
58 /**
59  * Post a callback to be run on the frame following the specified delay. The
60  * data pointer provided will be passed to the callback function when it's
61  * called.
62  */
63 void AChoreographer_postFrameCallbackDelayed(AChoreographer* choreographer,
64                 AChoreographer_frameCallback callback, void* data, long delayMillis);
65 __END_DECLS
66 
67 #endif // ANDROID_CHOREOGRAPHER_H
68 
69 /** @} */
70