MinikinSkia.cpp revision a3b9f2e3c66ec485f3b712560d52e31632a9cbe8 
1/*
2 * Copyright (C) 2013 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#include "MinikinSkia.h"
18
19#include <log/log.h>
20
21#include <SkPaint.h>
22#include <SkTypeface.h>
23
24namespace android {
25
26MinikinFontSkia::MinikinFontSkia(sk_sp<SkTypeface> typeface, const void* fontData, size_t fontSize,
27        int ttcIndex) :
28    minikin::MinikinFont(typeface->uniqueID()), mTypeface(std::move(typeface)), mFontData(fontData),
29    mFontSize(fontSize), mTtcIndex(ttcIndex) {
30}
31
32static void MinikinFontSkia_SetSkiaPaint(const minikin::MinikinFont* font, SkPaint* skPaint,
33        const minikin::MinikinPaint& paint) {
34    skPaint->setTextEncoding(SkPaint::kGlyphID_TextEncoding);
35    skPaint->setTextSize(paint.size);
36    skPaint->setTextScaleX(paint.scaleX);
37    skPaint->setTextSkewX(paint.skewX);
38    MinikinFontSkia::unpackPaintFlags(skPaint, paint.paintFlags);
39    // Apply font fakery on top of user-supplied flags.
40    MinikinFontSkia::populateSkPaint(skPaint, font, paint.fakery);
41}
42
43float MinikinFontSkia::GetHorizontalAdvance(uint32_t glyph_id,
44        const minikin::MinikinPaint &paint) const {
45    SkPaint skPaint;
46    uint16_t glyph16 = glyph_id;
47    SkScalar skWidth;
48    MinikinFontSkia_SetSkiaPaint(this, &skPaint, paint);
49    skPaint.getTextWidths(&glyph16, sizeof(glyph16), &skWidth, NULL);
50#ifdef VERBOSE
51    ALOGD("width for typeface %d glyph %d = %f", mTypeface->uniqueID(), glyph_id, skWidth);
52#endif
53    return skWidth;
54}
55
56void MinikinFontSkia::GetBounds(minikin::MinikinRect* bounds, uint32_t glyph_id,
57        const minikin::MinikinPaint& paint) const {
58    SkPaint skPaint;
59    uint16_t glyph16 = glyph_id;
60    SkRect skBounds;
61    MinikinFontSkia_SetSkiaPaint(this, &skPaint, paint);
62    skPaint.getTextWidths(&glyph16, sizeof(glyph16), NULL, &skBounds);
63    bounds->mLeft = skBounds.fLeft;
64    bounds->mTop = skBounds.fTop;
65    bounds->mRight = skBounds.fRight;
66    bounds->mBottom = skBounds.fBottom;
67}
68
69SkTypeface *MinikinFontSkia::GetSkTypeface() const {
70    return mTypeface.get();
71}
72
73sk_sp<SkTypeface> MinikinFontSkia::RefSkTypeface() const {
74    return mTypeface;
75}
76
77const void* MinikinFontSkia::GetFontData() const {
78    return mFontData;
79}
80
81size_t MinikinFontSkia::GetFontSize() const {
82    return mFontSize;
83}
84
85int MinikinFontSkia::GetFontIndex() const {
86    return mTtcIndex;
87}
88
89uint32_t MinikinFontSkia::packPaintFlags(const SkPaint* paint) {
90    uint32_t flags = paint->getFlags();
91    SkPaint::Hinting hinting = paint->getHinting();
92    // select only flags that might affect text layout
93    flags &= (SkPaint::kAntiAlias_Flag | SkPaint::kFakeBoldText_Flag | SkPaint::kLinearText_Flag |
94            SkPaint::kSubpixelText_Flag | SkPaint::kDevKernText_Flag |
95            SkPaint::kEmbeddedBitmapText_Flag | SkPaint::kAutoHinting_Flag |
96            SkPaint::kVerticalText_Flag);
97    flags |= (hinting << 16);
98    return flags;
99}
100
101void MinikinFontSkia::unpackPaintFlags(SkPaint* paint, uint32_t paintFlags) {
102    paint->setFlags(paintFlags & SkPaint::kAllFlags);
103    paint->setHinting(static_cast<SkPaint::Hinting>(paintFlags >> 16));
104}
105
106void MinikinFontSkia::populateSkPaint(SkPaint* paint, const MinikinFont* font,
107        minikin::FontFakery fakery) {
108    paint->setTypeface(reinterpret_cast<const MinikinFontSkia*>(font)->RefSkTypeface());
109    paint->setFakeBoldText(paint->isFakeBoldText() || fakery.isFakeBold());
110    if (fakery.isFakeItalic()) {
111        paint->setTextSkewX(paint->getTextSkewX() - 0.25f);
112    }
113}
114
115}
116