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