TreeInfo.h revision 8c31e1db2a2cea4278503d6b9b27bca87946ef36 
1/*
2 * Copyright (C) 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#pragma once
18
19#include "utils/Macros.h"
20
21#include <utils/Timers.h>
22
23#include <string>
24
25namespace android {
26namespace uirenderer {
27
28namespace renderthread {
29class CanvasContext;
30}
31
32class DamageAccumulator;
33class LayerUpdateQueue;
34class RenderNode;
35class RenderState;
36
37class ErrorHandler {
38public:
39    virtual void onError(const std::string& message) = 0;
40protected:
41    ~ErrorHandler() {}
42};
43
44class TreeObserver {
45public:
46    // Called when a RenderNode's parent count hits 0.
47    // Due to the unordered nature of tree pushes, once prepareTree
48    // is finished it is possible that the node was "resurrected" and has
49    // a non-zero parent count.
50    virtual void onMaybeRemovedFromTree(RenderNode* node) = 0;
51protected:
52    virtual ~TreeObserver() {}
53};
54
55// This would be a struct, but we want to PREVENT_COPY_AND_ASSIGN
56class TreeInfo {
57    PREVENT_COPY_AND_ASSIGN(TreeInfo);
58public:
59    enum TraversalMode {
60        // The full monty - sync, push, run animators, etc... Used by DrawFrameTask
61        // May only be used if both the UI thread and RT thread are blocked on the
62        // prepare
63        MODE_FULL,
64        // Run only what can be done safely on RT thread. Currently this only means
65        // animators, but potentially things like SurfaceTexture updates
66        // could be handled by this as well if there are no listeners
67        MODE_RT_ONLY,
68    };
69
70    TreeInfo(TraversalMode mode, renderthread::CanvasContext& canvasContext)
71            : mode(mode)
72            , prepareTextures(mode == MODE_FULL)
73            , canvasContext(canvasContext)
74    {}
75
76    TraversalMode mode;
77    // TODO: Remove this? Currently this is used to signal to stop preparing
78    // textures if we run out of cache space.
79    bool prepareTextures;
80    renderthread::CanvasContext& canvasContext;
81    // TODO: buildLayer uses this to suppress running any animations, but this
82    // should probably be refactored somehow. The reason this is done is
83    // because buildLayer is not setup for injecting the animationHook, as well
84    // as this being otherwise wasted work as all the animators will be
85    // re-evaluated when the frame is actually drawn
86    bool runAnimations = true;
87
88    // Must not be null during actual usage
89    DamageAccumulator* damageAccumulator = nullptr;
90
91    LayerUpdateQueue* layerUpdateQueue = nullptr;
92    ErrorHandler* errorHandler = nullptr;
93
94    bool updateWindowPositions = false;
95
96    struct Out {
97        bool hasFunctors = false;
98        // This is only updated if evaluateAnimations is true
99        bool hasAnimations = false;
100        // This is set to true if there is an animation that RenderThread cannot
101        // animate itself, such as if hasFunctors is true
102        // This is only set if hasAnimations is true
103        bool requiresUiRedraw = false;
104        // This is set to true if draw() can be called this frame
105        // false means that we must delay until the next vsync pulse as frame
106        // production is outrunning consumption
107        // NOTE that if this is false CanvasContext will set either requiresUiRedraw
108        // *OR* will post itself for the next vsync automatically, use this
109        // only to avoid calling draw()
110        bool canDrawThisFrame = true;
111    } out;
112
113    // This flag helps to disable projection for receiver nodes that do not have any backward
114    // projected children.
115    bool hasBackwardProjectedNodes = false;
116    // TODO: Damage calculations
117};
118
119} /* namespace uirenderer */
120} /* namespace android */
121