TextDropShadowCache.h revision 059e12ccd20f5c249724a8362d6bac325334ea76 
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 "FontRenderer.h"
28#include "Texture.h"
29
30namespace android {
31namespace uirenderer {
32
33struct ShadowText {
34    ShadowText(): len(0), radius(0.0f), textSize(0.0f), typeface(NULL),
35            flags(0), italicStyle(0.0f), scaleX(0), text(NULL), positions(NULL) {
36    }
37
38    ShadowText(SkPaint* paint, float radius, uint32_t len, const char* srcText,
39            const float* positions):
40            len(len), radius(radius), positions(positions) {
41        // TODO: Propagate this through the API, we should not cast here
42        text = (const char16_t*) srcText;
43
44        textSize = paint->getTextSize();
45        typeface = paint->getTypeface();
46
47        flags = 0;
48        if (paint->isFakeBoldText()) {
49            flags |= Font::kFakeBold;
50        }
51
52        italicStyle = paint->getTextSkewX();
53        scaleX = paint->getTextScaleX();
54    }
55
56    ~ShadowText() {
57    }
58
59    hash_t hash() const;
60
61    static int compare(const ShadowText& lhs, const ShadowText& rhs);
62
63    bool operator==(const ShadowText& other) const {
64        return compare(*this, other) == 0;
65    }
66
67    bool operator!=(const ShadowText& other) const {
68        return compare(*this, other) != 0;
69    }
70
71    void copyTextLocally() {
72        str.setTo((const char16_t*) text, len * sizeof(char16_t));
73        text = str.string();
74        if (positions != NULL) {
75            positionsCopy.clear();
76            positionsCopy.appendArray(positions, len);
77            positions = positionsCopy.array();
78        }
79    }
80
81    uint32_t len;
82    float radius;
83    float textSize;
84    SkTypeface* typeface;
85    uint32_t flags;
86    float italicStyle;
87    float scaleX;
88    const char16_t* text;
89    const float* positions;
90
91    // Not directly used to compute the cache key
92    String16 str;
93    Vector<float> positionsCopy;
94
95}; // struct ShadowText
96
97// Caching support
98
99inline int strictly_order_type(const ShadowText& lhs, const ShadowText& rhs) {
100    return ShadowText::compare(lhs, rhs) < 0;
101}
102
103inline int compare_type(const ShadowText& lhs, const ShadowText& rhs) {
104    return ShadowText::compare(lhs, rhs);
105}
106
107inline hash_t hash_type(const ShadowText& entry) {
108    return entry.hash();
109}
110
111/**
112 * Alpha texture used to represent a shadow.
113 */
114struct ShadowTexture: public Texture {
115    ShadowTexture(): Texture() {
116    }
117
118    float left;
119    float top;
120}; // struct ShadowTexture
121
122class TextDropShadowCache: public OnEntryRemoved<ShadowText, ShadowTexture*> {
123public:
124    TextDropShadowCache();
125    TextDropShadowCache(uint32_t maxByteSize);
126    ~TextDropShadowCache();
127
128    /**
129     * Used as a callback when an entry is removed from the cache.
130     * Do not invoke directly.
131     */
132    void operator()(ShadowText& text, ShadowTexture*& texture);
133
134    ShadowTexture* get(SkPaint* paint, const char* text, uint32_t len,
135            int numGlyphs, float radius, const float* positions);
136
137    /**
138     * Clears the cache. This causes all textures to be deleted.
139     */
140    void clear();
141
142    void setFontRenderer(FontRenderer& fontRenderer) {
143        mRenderer = &fontRenderer;
144    }
145
146    /**
147     * Sets the maximum size of the cache in bytes.
148     */
149    void setMaxSize(uint32_t maxSize);
150    /**
151     * Returns the maximum size of the cache in bytes.
152     */
153    uint32_t getMaxSize();
154    /**
155     * Returns the current size of the cache in bytes.
156     */
157    uint32_t getSize();
158
159private:
160    void init();
161
162    LruCache<ShadowText, ShadowTexture*> mCache;
163
164    uint32_t mSize;
165    uint32_t mMaxSize;
166    FontRenderer* mRenderer;
167    bool mDebugEnabled;
168}; // class TextDropShadowCache
169
170}; // namespace uirenderer
171}; // namespace android
172
173#endif // ANDROID_HWUI_TEXT_DROP_SHADOW_CACHE_H
174