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 
30 namespace android {
31 namespace uirenderer {
32 
33 class Caches;
34 class FontRenderer;
35 
36 struct ShadowText {
ShadowTextShadowText37     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
ShadowTextShadowText42     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 
~ShadowTextShadowText60     ~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 
copyTextLocallyShadowText75     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 
strictly_order_type(const ShadowText & lhs,const ShadowText & rhs)104 inline int strictly_order_type(const ShadowText& lhs, const ShadowText& rhs) {
105     return ShadowText::compare(lhs, rhs) < 0;
106 }
107 
compare_type(const ShadowText & lhs,const ShadowText & rhs)108 inline int compare_type(const ShadowText& lhs, const ShadowText& rhs) {
109     return ShadowText::compare(lhs, rhs);
110 }
111 
hash_type(const ShadowText & entry)112 inline hash_t hash_type(const ShadowText& entry) {
113     return entry.hash();
114 }
115 
116 /**
117  * Alpha texture used to represent a shadow.
118  */
119 struct ShadowTexture: public Texture {
ShadowTextureShadowTexture120     ShadowTexture(Caches& caches): Texture(caches) {
121     }
122 
123     float left;
124     float top;
125 }; // struct ShadowTexture
126 
127 class TextDropShadowCache: public OnEntryRemoved<ShadowText, ShadowTexture*> {
128 public:
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 
setFontRenderer(FontRenderer & fontRenderer)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 
164 private:
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