DamageAccumulator.cpp revision e4267ea4f20740c37c01bfb6aefcf61fddc4566a 
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#define LOG_TAG "DamageAccumulator"
18
19#include "DamageAccumulator.h"
20
21#include <cutils/log.h>
22
23#include "RenderNode.h"
24#include "utils/MathUtils.h"
25
26namespace android {
27namespace uirenderer {
28
29struct DirtyStack {
30    const RenderNode* node;
31    // When this frame is pop'd, this rect is mapped through the above transform
32    // and applied to the previous (aka parent) frame
33    SkRect pendingDirty;
34    DirtyStack* prev;
35    DirtyStack* next;
36};
37
38DamageAccumulator::DamageAccumulator() {
39    mHead = (DirtyStack*) mAllocator.alloc(sizeof(DirtyStack));
40    memset(mHead, 0, sizeof(DirtyStack));
41    // Create a root that we will not pop off
42    mHead->prev = mHead;
43}
44
45void DamageAccumulator::pushNode(const RenderNode* node) {
46    if (!mHead->next) {
47        DirtyStack* nextFrame = (DirtyStack*) mAllocator.alloc(sizeof(DirtyStack));
48        nextFrame->next = 0;
49        nextFrame->prev = mHead;
50        mHead->next = nextFrame;
51    }
52    mHead = mHead->next;
53    mHead->node = node;
54    mHead->pendingDirty.setEmpty();
55}
56
57void DamageAccumulator::popNode() {
58    LOG_ALWAYS_FATAL_IF(mHead->prev == mHead, "Cannot pop the root frame!");
59    DirtyStack* dirtyFrame = mHead;
60    mHead = mHead->prev;
61    if (!dirtyFrame->pendingDirty.isEmpty()) {
62        SkRect mappedDirty;
63        const RenderProperties& props = dirtyFrame->node->properties();
64        const SkMatrix* transform = props.getTransformMatrix();
65        if (transform && !transform->isIdentity()) {
66            transform->mapRect(&mappedDirty, dirtyFrame->pendingDirty);
67        } else {
68            mappedDirty = dirtyFrame->pendingDirty;
69        }
70        if (CC_LIKELY(mHead->node)) {
71            const RenderProperties& parentProps = mHead->node->properties();
72            mappedDirty.offset(props.getLeft() - parentProps.getScrollX(),
73                    props.getTop() - parentProps.getScrollY());
74            if (props.getClipToBounds()) {
75                if (!mappedDirty.intersect(0, 0, parentProps.getWidth(), parentProps.getHeight())) {
76                    mappedDirty.setEmpty();
77                }
78            }
79            if (CC_UNLIKELY(!MathUtils::isZero(props.getTranslationZ()))) {
80                // TODO: Can we better bound the shadow damage area? For now
81                // match the old damageShadowReceiver() path and just dirty
82                // the entire parent bounds
83                mappedDirty.join(0, 0, parentProps.getWidth(), parentProps.getHeight());
84            }
85        } else {
86            mappedDirty.offset(props.getLeft(), props.getTop());
87        }
88        dirty(mappedDirty.fLeft, mappedDirty.fTop, mappedDirty.fRight, mappedDirty.fBottom);
89    }
90}
91
92void DamageAccumulator::dirty(float left, float top, float right, float bottom) {
93    mHead->pendingDirty.join(left, top, right, bottom);
94}
95
96void DamageAccumulator::finish(SkRect* totalDirty) {
97    LOG_ALWAYS_FATAL_IF(mHead->prev != mHead, "Cannot finish, mismatched push/pop calls! %p vs. %p", mHead->prev, mHead);
98    // Root node never has a transform, so this is the fully mapped dirty rect
99    *totalDirty = mHead->pendingDirty;
100    totalDirty->roundOut();
101    mHead->pendingDirty.setEmpty();
102}
103
104} /* namespace uirenderer */
105} /* namespace android */
106