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 #include "MinikinUtils.h"
17 
18 #include "Paint.h"
19 #include "SkPathMeasure.h"
20 #include "Typeface.h"
21 
22 #include <cutils/log.h>
23 #include <string>
24 
25 namespace android {
26 
prepareMinikinPaint(MinikinPaint * minikinPaint,FontCollection ** pFont,const Paint * paint,Typeface * typeface)27 FontStyle MinikinUtils::prepareMinikinPaint(MinikinPaint* minikinPaint, FontCollection** pFont,
28         const Paint* paint, Typeface* typeface) {
29     const Typeface* resolvedFace = Typeface::resolveDefault(typeface);
30     *pFont = resolvedFace->fFontCollection;
31     FontStyle resolved = resolvedFace->fStyle;
32 
33     /* Prepare minikin FontStyle */
34     FontVariant minikinVariant = (paint->getFontVariant() == VARIANT_ELEGANT) ? VARIANT_ELEGANT
35             : VARIANT_COMPACT;
36     const uint32_t langListId = paint->getMinikinLangListId();
37     FontStyle minikinStyle(langListId, minikinVariant, resolved.getWeight(), resolved.getItalic());
38 
39     /* Prepare minikin Paint */
40     // Note: it would be nice to handle fractional size values (it would improve smooth zoom
41     // behavior), but historically size has been treated as an int.
42     // TODO: explore whether to enable fractional sizes, possibly when linear text flag is set.
43     minikinPaint->size = (int)paint->getTextSize();
44     minikinPaint->scaleX = paint->getTextScaleX();
45     minikinPaint->skewX = paint->getTextSkewX();
46     minikinPaint->letterSpacing = paint->getLetterSpacing();
47     minikinPaint->paintFlags = MinikinFontSkia::packPaintFlags(paint);
48     minikinPaint->fontFeatureSettings = paint->getFontFeatureSettings();
49     minikinPaint->hyphenEdit = HyphenEdit(paint->getHyphenEdit());
50     return minikinStyle;
51 }
52 
doLayout(Layout * layout,const Paint * paint,int bidiFlags,Typeface * typeface,const uint16_t * buf,size_t start,size_t count,size_t bufSize)53 void MinikinUtils::doLayout(Layout* layout, const Paint* paint, int bidiFlags,
54         Typeface* typeface, const uint16_t* buf, size_t start, size_t count,
55         size_t bufSize) {
56     FontCollection *font;
57     MinikinPaint minikinPaint;
58     FontStyle minikinStyle = prepareMinikinPaint(&minikinPaint, &font, paint, typeface);
59     layout->setFontCollection(font);
60     layout->doLayout(buf, start, count, bufSize, bidiFlags, minikinStyle, minikinPaint);
61 }
62 
measureText(const Paint * paint,int bidiFlags,Typeface * typeface,const uint16_t * buf,size_t start,size_t count,size_t bufSize,float * advances)63 float MinikinUtils::measureText(const Paint* paint, int bidiFlags, Typeface* typeface,
64         const uint16_t* buf, size_t start, size_t count, size_t bufSize, float *advances) {
65     FontCollection *font;
66     MinikinPaint minikinPaint;
67     FontStyle minikinStyle = prepareMinikinPaint(&minikinPaint, &font, paint, typeface);
68     return Layout::measureText(buf, start, count, bufSize, bidiFlags, minikinStyle, minikinPaint,
69             font, advances);
70 }
71 
hasVariationSelector(Typeface * typeface,uint32_t codepoint,uint32_t vs)72 bool MinikinUtils::hasVariationSelector(Typeface* typeface, uint32_t codepoint, uint32_t vs) {
73     const Typeface* resolvedFace = Typeface::resolveDefault(typeface);
74     return resolvedFace->fFontCollection->hasVariationSelector(codepoint, vs);
75 }
76 
xOffsetForTextAlign(Paint * paint,const Layout & layout)77 float MinikinUtils::xOffsetForTextAlign(Paint* paint, const Layout& layout) {
78     switch (paint->getTextAlign()) {
79         case Paint::kCenter_Align:
80             return layout.getAdvance() * -0.5f;
81             break;
82         case Paint::kRight_Align:
83             return -layout.getAdvance();
84             break;
85         default:
86             break;
87     }
88     return 0;
89 }
90 
hOffsetForTextAlign(Paint * paint,const Layout & layout,const SkPath & path)91 float MinikinUtils::hOffsetForTextAlign(Paint* paint, const Layout& layout, const SkPath& path) {
92     float align = 0;
93     switch (paint->getTextAlign()) {
94         case Paint::kCenter_Align:
95             align = -0.5f;
96             break;
97         case Paint::kRight_Align:
98             align = -1;
99             break;
100         default:
101             return 0;
102     }
103     SkPathMeasure measure(path, false);
104     return align * (layout.getAdvance() - measure.getLength());
105 }
106 
107 }
108