1 /*
2  * Copyright (C) 2014 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 /**
18  * Utilities for making Minikin work, especially from existing objects like
19  * Paint and so on.
20  **/
21 
22  // TODO: does this really need to be separate from MinikinSkia?
23 
24 #ifndef _ANDROID_GRAPHICS_MINIKIN_UTILS_H_
25 #define _ANDROID_GRAPHICS_MINIKIN_UTILS_H_
26 
27 #include <cutils/compiler.h>
28 #include <minikin/Layout.h>
29 #include "Paint.h"
30 #include "MinikinSkia.h"
31 #include "Typeface.h"
32 
33 namespace android {
34 
35 class MinikinUtils {
36 public:
37     ANDROID_API static minikin::FontStyle prepareMinikinPaint(minikin::MinikinPaint* minikinPaint,
38             const Paint* paint, Typeface* typeface);
39 
40     ANDROID_API static minikin::Layout doLayout(const Paint* paint, int bidiFlags,
41             Typeface* typeface, const uint16_t* buf, size_t start, size_t count,
42             size_t bufSize);
43 
44     ANDROID_API static float measureText(const Paint* paint, int bidiFlags, Typeface* typeface,
45             const uint16_t* buf, size_t start, size_t count, size_t bufSize, float *advances);
46 
47     ANDROID_API static bool hasVariationSelector(Typeface* typeface, uint32_t codepoint,
48             uint32_t vs);
49 
50     ANDROID_API static float xOffsetForTextAlign(Paint* paint, const minikin::Layout& layout);
51 
52     ANDROID_API static float hOffsetForTextAlign(Paint* paint, const minikin::Layout& layout,
53             const SkPath& path);
54     // f is a functor of type void f(size_t start, size_t end);
55     template <typename F>
forFontRun(const minikin::Layout & layout,Paint * paint,F & f)56     ANDROID_API static void forFontRun(const minikin::Layout& layout, Paint* paint, F& f) {
57         float saveSkewX = paint->getTextSkewX();
58         bool savefakeBold = paint->isFakeBoldText();
59         const minikin::MinikinFont* curFont = nullptr;
60         size_t start = 0;
61         size_t nGlyphs = layout.nGlyphs();
62         for (size_t i = 0; i < nGlyphs; i++) {
63             const minikin::MinikinFont* nextFont = layout.getFont(i);
64             if (i > 0 && nextFont != curFont) {
65                 MinikinFontSkia::populateSkPaint(paint, curFont, layout.getFakery(start));
66                 f(start, i);
67                 paint->setTextSkewX(saveSkewX);
68                 paint->setFakeBoldText(savefakeBold);
69                 start = i;
70             }
71             curFont = nextFont;
72         }
73         if (nGlyphs > start) {
74             MinikinFontSkia::populateSkPaint(paint, curFont, layout.getFakery(start));
75             f(start, nGlyphs);
76             paint->setTextSkewX(saveSkewX);
77             paint->setFakeBoldText(savefakeBold);
78         }
79     }
80 };
81 
82 }  // namespace android
83 
84 #endif  // _ANDROID_GRAPHICS_MINIKIN_UTILS_H_
85