1// Copyright 2020 Google LLC. 2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file. 3#include "tools/fiddle/examples.h" 4REG_FIDDLE_ANIMATED(pong2, 512, 256, false, 0, 10) { 5static SkScalar PingPong(double t, SkScalar period, SkScalar phase, 6 SkScalar ends, SkScalar mid) { 7 double value = ::fmod(t + phase, period); 8 double half = period / 2.0; 9 double diff = ::fabs(value - half); 10 return SkDoubleToScalar(ends + (1.0 - diff / half) * (mid - ends)); 11} 12 13void draw(SkCanvas* canvas) { 14 float bX = PingPong(frame * duration, 2.5f, 0.0f, 0, 1) * 472 + 20; 15 float bY = PingPong(frame * duration, 2.0f, 0.4f, 0, 1) * 200 + 28; 16 17 SkPaint p; 18 p.setColor(SK_ColorWHITE); 19 p.setAntiAlias(true); 20 21 canvas->clear(SK_ColorBLACK); 22 canvas->drawRect(SkRect::MakeXYWH(492, bY - 15, 10, 30), p); 23 canvas->drawRect(SkRect::MakeXYWH(10, bY - 15, 10, 30), p); 24 canvas->drawCircle(bX, bY, 5, p); 25 26 const float intervals[] = { 12, 6 }; 27 p.setStrokeWidth(5); 28 p.setPathEffect(SkDashPathEffect::Make(intervals, SK_ARRAY_COUNT(intervals), 0)); 29 canvas->drawLine({256,0}, {256, 256}, p); 30} 31} // END FIDDLE 32