TextDropShadowCache.h revision e84a208317e0ed388fcdad1e6743c7849acb51b0 
1/*
2 * Copyright (C) 2010 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_HWUI_TEXT_DROP_SHADOW_CACHE_H
18#define ANDROID_HWUI_TEXT_DROP_SHADOW_CACHE_H
19
20#include <GLES2/gl2.h>
21
22#include <SkPaint.h>
23
24#include <utils/LruCache.h>
25#include <utils/String16.h>
26
27#include "font/Font.h"
28#include "Texture.h"
29
30namespace android {
31namespace uirenderer {
32
33class Caches;
34class FontRenderer;
35
36struct ShadowText {
37    ShadowText(): len(0), radius(0.0f), textSize(0.0f), typeface(nullptr),
38            flags(0), italicStyle(0.0f), scaleX(0), text(nullptr), positions(nullptr) {
39    }
40
41    // len is the number of bytes in text
42    ShadowText(const SkPaint* paint, float radius, uint32_t len, const char* srcText,
43            const float* positions):
44            len(len), radius(radius), positions(positions) {
45        // TODO: Propagate this through the API, we should not cast here
46        text = (const char16_t*) srcText;
47
48        textSize = paint->getTextSize();
49        typeface = paint->getTypeface();
50
51        flags = 0;
52        if (paint->isFakeBoldText()) {
53            flags |= Font::kFakeBold;
54        }
55
56        italicStyle = paint->getTextSkewX();
57        scaleX = paint->getTextScaleX();
58    }
59
60    ~ShadowText() {
61    }
62
63    hash_t hash() const;
64
65    static int compare(const ShadowText& lhs, const ShadowText& rhs);
66
67    bool operator==(const ShadowText& other) const {
68        return compare(*this, other) == 0;
69    }
70
71    bool operator!=(const ShadowText& other) const {
72        return compare(*this, other) != 0;
73    }
74
75    void copyTextLocally() {
76        uint32_t charCount = len / sizeof(char16_t);
77        str.setTo((const char16_t*) text, charCount);
78        text = str.string();
79        if (positions != nullptr) {
80            positionsCopy.clear();
81            positionsCopy.appendArray(positions, charCount * 2);
82            positions = positionsCopy.array();
83        }
84    }
85
86    uint32_t len;
87    float radius;
88    float textSize;
89    SkTypeface* typeface;
90    uint32_t flags;
91    float italicStyle;
92    float scaleX;
93    const char16_t* text;
94    const float* positions;
95
96    // Not directly used to compute the cache key
97    String16 str;
98    Vector<float> positionsCopy;
99
100}; // struct ShadowText
101
102// Caching support
103
104inline int strictly_order_type(const ShadowText& lhs, const ShadowText& rhs) {
105    return ShadowText::compare(lhs, rhs) < 0;
106}
107
108inline int compare_type(const ShadowText& lhs, const ShadowText& rhs) {
109    return ShadowText::compare(lhs, rhs);
110}
111
112inline hash_t hash_type(const ShadowText& entry) {
113    return entry.hash();
114}
115
116/**
117 * Alpha texture used to represent a shadow.
118 */
119struct ShadowTexture: public Texture {
120    ShadowTexture(Caches& caches): Texture(caches) {
121    }
122
123    float left;
124    float top;
125}; // struct ShadowTexture
126
127class TextDropShadowCache: public OnEntryRemoved<ShadowText, ShadowTexture*> {
128public:
129    TextDropShadowCache();
130    TextDropShadowCache(uint32_t maxByteSize);
131    ~TextDropShadowCache();
132
133    /**
134     * Used as a callback when an entry is removed from the cache.
135     * Do not invoke directly.
136     */
137    void operator()(ShadowText& text, ShadowTexture*& texture) override;
138
139    ShadowTexture* get(const SkPaint* paint, const char* text, uint32_t len,
140            int numGlyphs, float radius, const float* positions);
141
142    /**
143     * Clears the cache. This causes all textures to be deleted.
144     */
145    void clear();
146
147    void setFontRenderer(FontRenderer& fontRenderer) {
148        mRenderer = &fontRenderer;
149    }
150
151    /**
152     * Sets the maximum size of the cache in bytes.
153     */
154    void setMaxSize(uint32_t maxSize);
155    /**
156     * Returns the maximum size of the cache in bytes.
157     */
158    uint32_t getMaxSize();
159    /**
160     * Returns the current size of the cache in bytes.
161     */
162    uint32_t getSize();
163
164private:
165    void init();
166
167    LruCache<ShadowText, ShadowTexture*> mCache;
168
169    uint32_t mSize;
170    uint32_t mMaxSize;
171    FontRenderer* mRenderer;
172    bool mDebugEnabled;
173}; // class TextDropShadowCache
174
175}; // namespace uirenderer
176}; // namespace android
177
178#endif // ANDROID_HWUI_TEXT_DROP_SHADOW_CACHE_H
179