1 /*
2 * Copyright 2018 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkSGText.h"
9
10 #include "SkCanvas.h"
11 #include "SkPaint.h"
12 #include "SkPath.h"
13 #include "SkTArray.h"
14 #include "SkTypeface.h"
15
16 namespace sksg {
17
Make(sk_sp<SkTypeface> tf,const SkString & text)18 sk_sp<Text> Text::Make(sk_sp<SkTypeface> tf, const SkString& text) {
19 return sk_sp<Text>(new Text(std::move(tf), text));
20 }
21
Text(sk_sp<SkTypeface> tf,const SkString & text)22 Text::Text(sk_sp<SkTypeface> tf, const SkString& text)
23 : fTypeface(std::move(tf))
24 , fText(text) {}
25
26 Text::~Text() = default;
27
alignedPosition(SkScalar advance) const28 SkPoint Text::alignedPosition(SkScalar advance) const {
29 auto aligned = fPosition;
30
31 switch (fAlign) {
32 case SkTextUtils::kLeft_Align:
33 break;
34 case SkTextUtils::kCenter_Align:
35 aligned.offset(-advance / 2, 0);
36 break;
37 case SkTextUtils::kRight_Align:
38 aligned.offset(-advance, 0);
39 break;
40 }
41
42 return aligned;
43 }
44
onRevalidate(InvalidationController *,const SkMatrix &)45 SkRect Text::onRevalidate(InvalidationController*, const SkMatrix&) {
46 // TODO: we could potentially track invals which don't require rebuilding the blob.
47
48 SkFont font;
49 font.setTypeface(fTypeface);
50 font.setSize(fSize);
51 font.setScaleX(fScaleX);
52 font.setSkewX(fSkewX);
53 font.setEdging(fEdging);
54 font.setHinting(fHinting);
55
56 // N.B.: fAlign is applied externally (in alignedPosition()), because
57 // 1) SkTextBlob has some trouble computing accurate bounds with alignment.
58 // 2) SkPaint::Align is slated for deprecation.
59
60 fBlob = SkTextBlob::MakeFromText(fText.c_str(), fText.size(), font, kUTF8_SkTextEncoding);
61 if (!fBlob) {
62 return SkRect::MakeEmpty();
63 }
64
65 const auto& bounds = fBlob->bounds();
66 const auto aligned_pos = this->alignedPosition(bounds.width());
67
68 return bounds.makeOffset(aligned_pos.x(), aligned_pos.y());
69 }
70
onDraw(SkCanvas * canvas,const SkPaint & paint) const71 void Text::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
72 const auto aligned_pos = this->alignedPosition(this->bounds().width());
73 canvas->drawTextBlob(fBlob, aligned_pos.x(), aligned_pos.y(), paint);
74 }
75
onAsPath() const76 SkPath Text::onAsPath() const {
77 // TODO
78 return SkPath();
79 }
80
onClip(SkCanvas * canvas,bool antiAlias) const81 void Text::onClip(SkCanvas* canvas, bool antiAlias) const {
82 canvas->clipPath(this->asPath(), antiAlias);
83 }
84
Make(sk_sp<SkTextBlob> blob)85 sk_sp<TextBlob> TextBlob::Make(sk_sp<SkTextBlob> blob) {
86 return sk_sp<TextBlob>(new TextBlob(std::move(blob)));
87 }
88
TextBlob(sk_sp<SkTextBlob> blob)89 TextBlob::TextBlob(sk_sp<SkTextBlob> blob)
90 : fBlob(std::move(blob)) {}
91
92 TextBlob::~TextBlob() = default;
93
onRevalidate(InvalidationController *,const SkMatrix &)94 SkRect TextBlob::onRevalidate(InvalidationController*, const SkMatrix&) {
95 return fBlob ? fBlob->bounds() : SkRect::MakeEmpty();
96 }
97
onDraw(SkCanvas * canvas,const SkPaint & paint) const98 void TextBlob::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
99 canvas->drawTextBlob(fBlob, fPosition.x(), fPosition.y(), paint);
100 }
101
onAsPath() const102 SkPath TextBlob::onAsPath() const {
103 // TODO
104 return SkPath();
105 }
106
onClip(SkCanvas * canvas,bool antiAlias) const107 void TextBlob::onClip(SkCanvas* canvas, bool antiAlias) const {
108 canvas->clipPath(this->asPath(), antiAlias);
109 }
110
111 } // namespace sksg
112