TextDropShadowCache.h revision 726aeba80ffc6778a9bc3e0ee957b8d644183505 
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/String16.h>
25
26#include "utils/Compare.h"
27#include "utils/GenerationCache.h"
28#include "FontRenderer.h"
29#include "Texture.h"
30
31namespace android {
32namespace uirenderer {
33
34struct ShadowText {
35    ShadowText(): radius(0), len(0), textSize(0.0f), typeface(NULL) {
36    }
37
38    ShadowText(SkPaint* paint, uint32_t radius, uint32_t len, const char* srcText):
39            radius(radius), len(len) {
40        // TODO: Propagate this through the API, we should not cast here
41        text = (const char16_t*) srcText;
42
43        textSize = paint->getTextSize();
44        typeface = paint->getTypeface();
45
46        flags = 0;
47        if (paint->isFakeBoldText()) {
48            flags |= Font::kFakeBold;
49        }
50
51        const float skewX = paint->getTextSkewX();
52        italicStyle = *(uint32_t*) &skewX;
53
54        const float scaleXFloat = paint->getTextScaleX();
55        scaleX = *(uint32_t*) &scaleXFloat;
56    }
57
58    ~ShadowText() {
59    }
60
61    uint32_t radius;
62    uint32_t len;
63    float textSize;
64    SkTypeface* typeface;
65    uint32_t flags;
66    uint32_t italicStyle;
67    uint32_t scaleX;
68    const char16_t* text;
69    String16 str;
70
71    void copyTextLocally() {
72        str.setTo((const char16_t*) text, len >> 1);
73        text = str.string();
74    }
75
76    bool operator<(const ShadowText& rhs) const {
77        LTE_INT(len) {
78            LTE_INT(radius) {
79                LTE_FLOAT(textSize) {
80                    LTE_INT(typeface) {
81                        LTE_INT(flags) {
82                            LTE_INT(italicStyle) {
83                                LTE_INT(scaleX) {
84                                    return strncmp16(text, rhs.text, len >> 1) < 0;
85                                }
86                            }
87                        }
88                    }
89                }
90            }
91        }
92        return false;
93    }
94}; // struct ShadowText
95
96/**
97 * Alpha texture used to represent a shadow.
98 */
99struct ShadowTexture: public Texture {
100    ShadowTexture(): Texture() {
101    }
102
103    float left;
104    float top;
105}; // struct ShadowTexture
106
107class TextDropShadowCache: public OnEntryRemoved<ShadowText, ShadowTexture*> {
108public:
109    TextDropShadowCache();
110    TextDropShadowCache(uint32_t maxByteSize);
111    ~TextDropShadowCache();
112
113    /**
114     * Used as a callback when an entry is removed from the cache.
115     * Do not invoke directly.
116     */
117    void operator()(ShadowText& text, ShadowTexture*& texture);
118
119    ShadowTexture* get(SkPaint* paint, const char* text, uint32_t len,
120            int numGlyphs, uint32_t radius);
121
122    /**
123     * Clears the cache. This causes all textures to be deleted.
124     */
125    void clear();
126
127    void setFontRenderer(FontRenderer& fontRenderer) {
128        mRenderer = &fontRenderer;
129    }
130
131    /**
132     * Sets the maximum size of the cache in bytes.
133     */
134    void setMaxSize(uint32_t maxSize);
135    /**
136     * Returns the maximum size of the cache in bytes.
137     */
138    uint32_t getMaxSize();
139    /**
140     * Returns the current size of the cache in bytes.
141     */
142    uint32_t getSize();
143
144private:
145    void init();
146
147    GenerationCache<ShadowText, ShadowTexture*> mCache;
148
149    uint32_t mSize;
150    uint32_t mMaxSize;
151    FontRenderer* mRenderer;
152    bool mDebugEnabled;
153}; // class TextDropShadowCache
154
155}; // namespace uirenderer
156}; // namespace android
157
158#endif // ANDROID_HWUI_TEXT_DROP_SHADOW_CACHE_H
159