1 /*
2  * Copyright 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 ANDROID_SF_DISPLAY_SURFACE_H
18 #define ANDROID_SF_DISPLAY_SURFACE_H
19 
20 #include <utils/Errors.h>
21 #include <utils/RefBase.h>
22 #include <utils/StrongPointer.h>
23 
24 // ---------------------------------------------------------------------------
25 namespace android {
26 // ---------------------------------------------------------------------------
27 
28 class IGraphicBufferProducer;
29 class String8;
30 
31 class DisplaySurface : public virtual RefBase {
32 public:
33     // beginFrame is called at the beginning of the composition loop, before
34     // the configuration is known. The DisplaySurface should do anything it
35     // needs to do to enable HWComposer to decide how to compose the frame.
36     // We pass in mustRecompose so we can keep VirtualDisplaySurface's state
37     // machine happy without actually queueing a buffer if nothing has changed.
38     virtual status_t beginFrame(bool mustRecompose) = 0;
39 
40     // prepareFrame is called after the composition configuration is known but
41     // before composition takes place. The DisplaySurface can use the
42     // composition type to decide how to manage the flow of buffers between
43     // GLES and HWC for this frame.
44     enum CompositionType {
45         COMPOSITION_UNKNOWN = 0,
46         COMPOSITION_GLES    = 1,
47         COMPOSITION_HWC     = 2,
48         COMPOSITION_MIXED   = COMPOSITION_GLES | COMPOSITION_HWC
49     };
50     virtual status_t prepareFrame(CompositionType compositionType) = 0;
51 
52     // Should be called when composition rendering is complete for a frame (but
53     // eglSwapBuffers hasn't necessarily been called). Required by certain
54     // older drivers for synchronization.
55     // TODO: Remove this when we drop support for HWC 1.0.
56     virtual status_t compositionComplete() = 0;
57 
58     // Inform the surface that GLES composition is complete for this frame, and
59     // the surface should make sure that HWComposer has the correct buffer for
60     // this frame. Some implementations may only push a new buffer to
61     // HWComposer if GLES composition took place, others need to push a new
62     // buffer on every frame.
63     //
64     // advanceFrame must be followed by a call to  onFrameCommitted before
65     // advanceFrame may be called again.
66     virtual status_t advanceFrame() = 0;
67 
68     // onFrameCommitted is called after the frame has been committed to the
69     // hardware composer. The surface collects the release fence for this
70     // frame's buffer.
71     virtual void onFrameCommitted() = 0;
72 
73     virtual void dumpAsString(String8& result) const = 0;
74 
75     virtual void resizeBuffers(const uint32_t w, const uint32_t h) = 0;
76 
77 protected:
DisplaySurface()78     DisplaySurface() {}
~DisplaySurface()79     virtual ~DisplaySurface() {}
80 };
81 
82 // ---------------------------------------------------------------------------
83 } // namespace android
84 // ---------------------------------------------------------------------------
85 
86 #endif // ANDROID_SF_DISPLAY_SURFACE_H
87 
88