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 #include "include/core/SkCanvas.h" 8 #include "include/core/SkFont.h" 9 #include "include/core/SkPath.h" 10 #include "include/core/SkRRect.h" 11 #include "include/core/SkTypeface.h" 12 #include "src/base/SkRandom.h" 13 #include "tools/ToolUtils.h" 14 #include "tools/fonts/FontToolUtils.h" 15 #include "tools/timer/TimeUtils.h" 16 #include "tools/viewer/Slide.h" 17 18 #include <cmath> 19 20 // Implementation in C++ of Animated Emoji 21 // See https://t.d3fc.io/status/705212795936247808 22 // See https://crbug.com/848616 23 24 class GlyphTransformView : public Slide { 25 public: GlyphTransformView()26 GlyphTransformView() { fName = "Glyph Transform"; } 27 load(SkScalar w,SkScalar h)28 void load(SkScalar w, SkScalar h) override { 29 fEmojiFont = ToolUtils::EmojiSample(); 30 fSize = {w, h}; 31 } 32 resize(SkScalar w,SkScalar h)33 void resize(SkScalar w, SkScalar h) override { fSize = {w, h}; } 34 draw(SkCanvas * canvas)35 void draw(SkCanvas* canvas) override { 36 SkPaint paint; 37 38 SkFont font(fEmojiFont.typeface); 39 const char* text = fEmojiFont.sampleText; 40 41 double baseline = fSize.height() / 2; 42 canvas->drawLine(0, baseline, fSize.width(), baseline, paint); 43 44 SkMatrix ctm; 45 ctm.setRotate(fRotate); // d3 rotate takes degrees 46 ctm.postScale(fScale * 4, fScale * 4); 47 ctm.postTranslate(fTranslate.fX + fSize.width() * 0.8, fTranslate.fY + baseline); 48 canvas->concat(ctm); 49 50 // d3 by default anchors text around the middle 51 SkRect bounds; 52 font.measureText(text, strlen(text), SkTextEncoding::kUTF8, &bounds); 53 canvas->drawSimpleText(text, strlen(text), SkTextEncoding::kUTF8, -bounds.centerX(), -bounds.centerY(), 54 font, paint); 55 } 56 animate(double nanos)57 bool animate(double nanos) override { 58 constexpr SkScalar maxt = 100000; 59 double t = TimeUtils::PingPong(1e-9 * nanos, 20, 0, 0, maxt); // d3 t is in milliseconds 60 61 fTranslate.set(sin(t / 3000) - t * fSize.width() * 0.7 / maxt, sin(t / 999) / t); 62 fScale = 4.5 - std::sqrt(t) / 99; 63 fRotate = sin(t / 734); 64 65 return true; 66 } 67 68 private: 69 ToolUtils::EmojiTestSample fEmojiFont; 70 71 SkVector fTranslate; 72 SkScalar fScale; 73 SkScalar fRotate; 74 SkSize fSize; 75 }; 76 77 ////////////////////////////////////////////////////////////////////////////// 78 79 DEF_SLIDE( return new GlyphTransformView(); ) 80