1/*
2 * Copyright (C) 2018 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "DisplayList.h"
29#include "FontCascade.h"
30#include "Logging.h"
31#include "TextRun.h"
32#include <wtf/HashMap.h>
33#include <wtf/MemoryPressureHandler.h>
34#include <wtf/NeverDestroyed.h>
35
36namespace WebCore {
37
38template<typename LayoutRun>
39class GlyphDisplayListCache {
40public:
41 GlyphDisplayListCache() = default;
42
43 static GlyphDisplayListCache& singleton()
44 {
45 static NeverDestroyed<GlyphDisplayListCache> cache;
46 return cache;
47 }
48
49 DisplayList::DisplayList* get(const LayoutRun& run, const FontCascade& font, GraphicsContext& context, const TextRun& textRun)
50 {
51 if (MemoryPressureHandler::singleton().isUnderMemoryPressure()) {
52 if (!m_glyphRunMap.isEmpty()) {
53 LOG(MemoryPressure, "GlyphDisplayListCache::%s - Under memory pressure - size: %d - sizeInBytes: %ld", __FUNCTION__, size(), sizeInBytes());
54 clear();
55 }
56 return nullptr;
57 }
58
59 if (auto displayList = m_glyphRunMap.get(&run))
60 return displayList;
61
62 if (auto displayList = font.displayListForTextRun(context, textRun))
63 return m_glyphRunMap.add(&run, WTFMove(displayList)).iterator->value.get();
64
65 return nullptr;
66 }
67
68 void remove(const LayoutRun& run)
69 {
70 m_glyphRunMap.remove(&run);
71 }
72
73 void clear()
74 {
75 m_glyphRunMap.clear();
76 }
77
78 unsigned size() const
79 {
80 return m_glyphRunMap.size();
81 }
82
83 size_t sizeInBytes() const
84 {
85 size_t sizeInBytes = 0;
86 for (const auto& entry : m_glyphRunMap)
87 sizeInBytes += entry.value->sizeInBytes();
88 return sizeInBytes;
89 }
90
91private:
92 using GlyphRunMap = HashMap<const LayoutRun*, std::unique_ptr<DisplayList::DisplayList>>;
93 GlyphRunMap m_glyphRunMap;
94};
95
96}
97