TextDropShadowCache.h revision cabfcc1364eb7e4de0b15b3574fba45027b45cfc 
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    // TODO: Should take into account fake bold and text skew
77    bool operator<(const ShadowText& rhs) const {
78        LTE_INT(len) {
79            LTE_INT(radius) {
80                LTE_FLOAT(textSize) {
81                    LTE_INT(typeface) {
82                        LTE_INT(flags) {
83                            LTE_INT(italicStyle) {
84                                LTE_INT(scaleX) {
85                                    return strncmp16(text, rhs.text, len >> 1) < 0;
86                                }
87                            }
88                        }
89                    }
90                }
91            }
92        }
93        return false;
94    }
95}; // struct ShadowText
96
97/**
98 * Alpha texture used to represent a shadow.
99 */
100struct ShadowTexture: public Texture {
101    ShadowTexture(): Texture() {
102    }
103
104    float left;
105    float top;
106}; // struct ShadowTexture
107
108class TextDropShadowCache: public OnEntryRemoved<ShadowText, ShadowTexture*> {
109public:
110    TextDropShadowCache();
111    TextDropShadowCache(uint32_t maxByteSize);
112    ~TextDropShadowCache();
113
114    /**
115     * Used as a callback when an entry is removed from the cache.
116     * Do not invoke directly.
117     */
118    void operator()(ShadowText& text, ShadowTexture*& texture);
119
120    ShadowTexture* get(SkPaint* paint, const char* text, uint32_t len,
121            int numGlyphs, uint32_t radius);
122
123    /**
124     * Clears the cache. This causes all textures to be deleted.
125     */
126    void clear();
127
128    void setFontRenderer(FontRenderer& fontRenderer) {
129        mRenderer = &fontRenderer;
130    }
131
132    /**
133     * Sets the maximum size of the cache in bytes.
134     */
135    void setMaxSize(uint32_t maxSize);
136    /**
137     * Returns the maximum size of the cache in bytes.
138     */
139    uint32_t getMaxSize();
140    /**
141     * Returns the current size of the cache in bytes.
142     */
143    uint32_t getSize();
144
145private:
146    void init();
147
148    GenerationCache<ShadowText, ShadowTexture*> mCache;
149
150    uint32_t mSize;
151    uint32_t mMaxSize;
152    FontRenderer* mRenderer;
153    bool mDebugEnabled;
154}; // class TextDropShadowCache
155
156}; // namespace uirenderer
157}; // namespace android
158
159#endif // ANDROID_HWUI_TEXT_DROP_SHADOW_CACHE_H
160