// Copyright 2015 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. import 'dart:sky'; import 'dart:math' as math; double timeBase = null; void beginFrame(double timeStamp) { tracing.begin('beginFrame'); if (timeBase == null) timeBase = timeStamp; double delta = timeStamp - timeBase; PictureRecorder recorder = new PictureRecorder(); final double devicePixelRatio = view.devicePixelRatio; Canvas canvas = new Canvas(recorder, new Rect.fromLTWH(0.0, 0.0, view.width * devicePixelRatio, view.height * devicePixelRatio)); canvas.scale(devicePixelRatio, devicePixelRatio); canvas.translate(view.width / 2.0, view.height / 2.0); canvas.rotate(math.PI * delta / 1800); canvas.drawRect(new Rect.fromLTRB(-100.0, -100.0, 100.0, 100.0), new Paint()..color = const Color.fromARGB(255, 0, 255, 0)); view.picture = recorder.endRecording(); view.scheduleFrame(); tracing.end('beginFrame'); } void main() { view.setFrameCallback(beginFrame); view.scheduleFrame(); }