1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "Sample.h"
#include "sk_tool_utils.h"
#include "SkAnimTimer.h"
#include "SkCanvas.h"
#include "SkPath.h"
#include "SkRandom.h"
#include "SkRRect.h"
#include "SkTypeface.h"
#include <cmath>
// Implementation in C++ of Animated Emoji
// See https://t.d3fc.io/status/705212795936247808
// See https://crbug.com/848616
class GlyphTransformView : public Sample {
public:
GlyphTransformView() {}
protected:
void onOnceBeforeDraw() override {
fEmojiFont.fTypeface = sk_tool_utils::emoji_typeface();
fEmojiFont.fText = sk_tool_utils::emoji_sample_text();
}
bool onQuery(Sample::Event* evt) override {
if (Sample::TitleQ(*evt)) {
Sample::TitleR(evt, "Glyph Transform");
return true;
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
SkPaint paint;
SkFont font(fEmojiFont.fTypeface);
const char* text = fEmojiFont.fText;
double baseline = this->height() / 2;
canvas->drawLine(0, baseline, this->width(), baseline, paint);
SkMatrix ctm;
ctm.setRotate(fRotate); // d3 rotate takes degrees
ctm.postScale(fScale * 4, fScale * 4);
ctm.postTranslate(fTranslate.fX + this->width() * 0.8, fTranslate.fY + baseline);
canvas->concat(ctm);
// d3 by default anchors text around the middle
SkRect bounds;
font.measureText(text, strlen(text), kUTF8_SkTextEncoding, &bounds);
canvas->drawSimpleText(text, strlen(text), kUTF8_SkTextEncoding, -bounds.centerX(), -bounds.centerY(),
font, paint);
}
bool onAnimate(const SkAnimTimer& timer) override {
constexpr SkScalar maxt = 100000;
double t = timer.pingPong(20, 0, 0, maxt); // d3 t is in milliseconds
fTranslate.set(sin(t / 3000) - t * this->width() * 0.7 / maxt, sin(t / 999) / t);
fScale = 4.5 - std::sqrt(t) / 99;
fRotate = sin(t / 734);
return true;
}
private:
struct EmojiFont {
sk_sp<SkTypeface> fTypeface;
const char* fText;
} fEmojiFont;
SkVector fTranslate;
SkScalar fScale;
SkScalar fRotate;
typedef Sample INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_SAMPLE( return new GlyphTransformView(); )
|
