| Hal Canary | 8800042 | 2020-01-15 11:51:12 -0500 | [diff] [blame] | 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" |
| 4 | REG_FIDDLE_ANIMATED(pong, 256, 256, false, 0, 10) { |
| 5 | static 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 | |
| 13 | void draw(SkCanvas* canvas) { |
| 14 | canvas->clear(SK_ColorBLACK); |
| 15 | float ballX = PingPong(frame * duration, 2.5f, 0.0f, 0.0f, 1.0f); |
| 16 | float ballY = PingPong(frame * duration, 2.0f, 0.4f, 0.0f, 1.0f); |
| 17 | |
| 18 | SkPaint p; |
| 19 | p.setColor(SK_ColorWHITE); |
| 20 | p.setAntiAlias(true); |
| 21 | |
| 22 | float bX = ballX * 472 + 20; |
| 23 | float bY = ballY * 200 + 28; |
| 24 | |
| 25 | if (canvas->getGrContext()) { |
| 26 | canvas->drawRect(SkRect::MakeXYWH(236, bY - 15, 10, 30), p); |
| 27 | bX -= 256; |
| 28 | } else { |
| 29 | canvas->drawRect(SkRect::MakeXYWH(10, bY - 15, 10, 30), p); |
| 30 | } |
| 31 | canvas->drawCircle(bX, bY, 5, p); |
| 32 | } |
| 33 | } // END FIDDLE |