Move all samples but swarm from client/samples/ to samples/ .

client/samples/spirodraw/Spirodraw.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-#library('spirodraw');
-
-#import('dart:dom');
-#source("ColorPicker.dart");
-// TODO(732): Reenable when this works in the VM.
-// #resource("spirodraw.css");
-
-void main() {
-  new Spirodraw().go();
-}
-
-class Spirodraw {
-
-  static double PI2 = Math.PI * 2;
-  Document doc;
-  // Scale factor used to scale wheel radius from 1-10 to pixels
-  int RUnits, rUnits, dUnits;
-  // Fixed radius, wheel radius, pen distance in pixels
-  double R, r, d; 
-  HTMLInputElement fixedRadiusSlider, wheelRadiusSlider, 
-    penRadiusSlider, penWidthSlider, speedSlider;
-  HTMLSelectElement inOrOut;
-  HTMLLabelElement numTurns;
-  HTMLDivElement mainDiv;
-  num lastX, lastY;
-  int height, width, xc, yc;
-  int maxTurns;
-  HTMLCanvasElement frontCanvas, backCanvas;
-  CanvasRenderingContext2D front, back;
-  HTMLCanvasElement paletteElement; 
-  ColorPicker colorPicker;
-  String penColor = "red";
-  int penWidth;
-  double rad = 0.0;
-  double stepSize;
-  bool animationEnabled = true;
-  int numPoints;
-  double speed;
-  bool run;
-  
-  Spirodraw() {
-    doc = window.document;
-    inOrOut = doc.getElementById("in_out");
-    fixedRadiusSlider = doc.getElementById("fixed_radius");
-    wheelRadiusSlider = doc.getElementById("wheel_radius");
-    penRadiusSlider = doc.getElementById("pen_radius");
-    penWidthSlider = doc.getElementById("pen_width");
-    speedSlider = doc.getElementById("speed");
-    numTurns = doc.getElementById("num_turns");
-    mainDiv = doc.getElementById("main");
-    frontCanvas = doc.getElementById("canvas");
-    front = frontCanvas.getContext("2d");
-    backCanvas = doc.createElement("canvas");
-    back = backCanvas.getContext("2d");
-    paletteElement = doc.getElementById("palette");
-    window.addEventListener('resize', (event) => onResize(), true);
-    initControlPanel();
-  }
-
-  void go() {
-    onResize();
-  }
-  
-  void onResize() {
-    height = window.innerHeight;
-    width = window.innerWidth - 270;
-    yc = height~/2;
-    xc = width~/2;
-    frontCanvas.height = height;
-    frontCanvas.width = width;
-    backCanvas.height = height;
-    backCanvas.width = width;
-    clear();
-  }
-  
-  void initControlPanel() {
-    inOrOut.addEventListener('change', (event) => refresh(), true);
-    fixedRadiusSlider.addEventListener('change', (event) => refresh(), true);
-    wheelRadiusSlider.addEventListener('change', (event) => refresh(), true);
-    speedSlider.addEventListener('change', (event) => onSpeedChange(), true);
-    penRadiusSlider.addEventListener('change', (event) => refresh(), true);
-    penWidthSlider.addEventListener('change', (event) => onPenWidthChange(), true);
-    colorPicker = new ColorPicker(paletteElement);
-    colorPicker.addListener((String color) => onColorChange(color));
-    doc.getElementById("start").addEventListener('click', (event) => start(), true);
-    doc.getElementById("stop").addEventListener('click', (event) => stop(), true);
-    doc.getElementById("clear").addEventListener('click', (event) => clear(), true);
-    doc.getElementById("lucky").addEventListener('click', (event) => lucky(), true);
-  }
-  
-  void onColorChange(String color) {
-    penColor = color;
-    drawFrame(rad);
-  }
-
-  void onSpeedChange() {
-    speed = speedSlider.valueAsNumber;
-    stepSize = calcStepSize();
-  }
-  
-  void onPenWidthChange() {
-    penWidth = penWidthSlider.valueAsNumber;
-    drawFrame(rad);
-  }
-  
-  void refresh() {
-    stop();
-    // Reset
-    lastX = lastY = 0;
-    // Compute fixed radius
-    // based on starting diameter == min / 2, fixed radius == 10 units
-    int min = Math.min(height, width);
-    double pixelsPerUnit = min / 40;
-    RUnits = fixedRadiusSlider.valueAsNumber;
-    R = RUnits * pixelsPerUnit;
-    // Scale inner radius and pen distance in units of fixed radius
-    rUnits = wheelRadiusSlider.valueAsNumber;
-    r = rUnits * R/RUnits * Math.parseInt(inOrOut.value);
-    dUnits = penRadiusSlider.valueAsNumber;
-    d = dUnits * R/RUnits;
-    numPoints = calcNumPoints();
-    maxTurns = calcTurns();
-    onSpeedChange();
-    numTurns.innerText = "0" + "/" + maxTurns;
-    penWidth = penWidthSlider.valueAsNumber;
-    drawFrame(0.0);
-  }
-
-  int calcNumPoints() {
-    if ((dUnits==0) || (rUnits==0))
-      // Empirically, treat it like an oval
-      return 2;
-    int gcf_ = gcf(RUnits, rUnits);
-    int n = RUnits ~/ gcf_;
-    int d_ = rUnits ~/ gcf_;
-    if (n % 2 == 1)
-      // odd
-      return n;
-    else if (d_ %2 == 1)
-      return n;
-    else
-      return n~/2;
-  }
-
-  // TODO return optimum step size in radians
-  double calcStepSize() => speed / 100 * maxTurns / numPoints;
-
-  void drawFrame(double theta) {
-    if (animationEnabled) {
-      front.clearRect(0, 0, width, height);
-      front.drawImage(backCanvas, 0, 0);
-      drawFixed();
-    }
-    drawWheel(theta);
-  }
-
-  void animate(int time) {
-    if (run && rad <= maxTurns * PI2) {
-      rad+=stepSize;
-      drawFrame(rad);
-      int nTurns = (rad / PI2).toInt();
-      numTurns.innerText = '${nTurns}/$maxTurns';
-      window.webkitRequestAnimationFrame(animate, frontCanvas);
-    } else {
-      stop();
-    }
-  }
-  
-  void start() {
-    refresh();
-    rad = 0.0;
-    run = true;
-    window.webkitRequestAnimationFrame(animate, frontCanvas); 
-  }
-
-  int calcTurns() {
-    // compute ratio of wheel radius to big R then find LCM
-    if ((dUnits==0) || (rUnits==0))
-      return 1;
-    int ru = rUnits.abs();
-    int wrUnits = RUnits + rUnits;
-    int g = gcf (wrUnits, ru);
-    return (ru ~/ g).toInt();
-  }
-
-  void stop() {
-    run = false;
-    // Show drawing only
-    front.clearRect(0, 0, width, height);
-    front.drawImage(backCanvas, 0, 0);
-    // Reset angle
-    rad = 0.0;
-  }
-
-  void clear() {
-    stop();
-    back.clearRect(0, 0, width, height);
-    refresh();
-  }
-
-  /**
-   * Choose random settings for wheel and pen, but
-   * leave fixed radius alone as it often changes
-   * things too much.
-   */
-  void lucky() {
-    wheelRadiusSlider.valueAsNumber = Math.random() * 9;
-    penRadiusSlider.valueAsNumber = Math.random() * 9;
-    penWidthSlider.valueAsNumber = 1 + Math.random() * 9;
-    colorPicker.selectedColor = Math.random() * 215;
-    start();
-  }
-
-  void drawFixed() {
-    if (animationEnabled) {
-      front.beginPath();
-      front.setLineWidth(2);
-      front.strokeStyle = "gray";
-      front.arc(xc, yc, R, 0, PI2, true);
-      front.closePath();
-      front.stroke();
-    }
-  }
-
-  /**
-   * Draw the wheel with its center at angle theta
-   * with respect to the fixed wheel
-   * 
-   * @param theta
-   */
-  void drawWheel(double theta) {
-    double wx = xc + ((R + r) * Math.cos(theta));
-    double wy = yc - ((R + r) * Math.sin(theta));
-    if (animationEnabled) {
-      if (rUnits>0) {
-        // Draw ring
-        front.beginPath();
-        front.arc(wx, wy, r.abs(), 0, PI2, true);
-        front.closePath();
-        front.stroke();
-        // Draw center
-        front.setLineWidth(1);
-        front.beginPath();
-        front.arc(wx, wy, 3, 0, PI2, true);
-        front.fillStyle = "black";
-        front.fill();
-        front.closePath();
-        front.stroke();
-      }
-    }
-    drawTip(wx, wy, theta);
-  }
-
-  /**
-   * Draw a rotating line that shows the wheel rolling and leaves
-   * the pen trace
-   * 
-   * @param wx X coordinate of wheel center
-   * @param wy Y coordinate of wheel center
-   * @param theta Angle of wheel center with respect to fixed circle
-   */
-  void drawTip(double wx, double wy, double theta) {
-    // Calc wheel rotation angle
-    double rot = (r==0) ? theta : theta * (R+r) / r;
-    // Find tip of line
-    double tx = wx + d * Math.cos(rot);
-    double ty = wy - d * Math.sin(rot);
-    if (animationEnabled) {
-      front.beginPath();
-      front.fillStyle = penColor;
-      front.arc(tx, ty, penWidth/2+2, 0, PI2, true);
-      front.fill();
-      front.moveTo(wx, wy);
-      front.strokeStyle = "black";
-      front.lineTo(tx, ty);
-      front.closePath();
-      front.stroke();
-    }
-    drawSegmentTo(tx, ty);
-  }
-
-  void drawSegmentTo(double tx, double ty) {
-    if (lastX > 0) {
-      back.beginPath();
-      back.strokeStyle = penColor;
-      back.setLineWidth(penWidth);
-      back.moveTo(lastX, lastY);
-      back.lineTo(tx, ty);
-      back.closePath();
-      back.stroke();
-    }
-    lastX = tx;
-    lastY = ty;
-  }
-  
-}
-
-int gcf(int n, int d) {
-  if (n==d)
-    return n;
-  int max = Math.max(n, d);
-  for (int i = max ~/ 2; i > 1; i--)
-    if ((n % i == 0) && (d % i == 0))
-      return i;
-  return 1;
-}