Path

Introduction

Path in curves, built-in object of phaser.

  • Author: Richard Davey

Usage

Add path object

var path = scene.add.path();
// var path = scene.add.path(x, y);  // curve start from (x, y)

or

var path = new Phaser.Curves.Path();
// var path = new Phaser.Curves.Path(x, y);  // curve start from (x, y)

Add path object with curves

Curves in JSON

var path = scene.add.path(json);
or
var path = new Phaser.Curves.Path(json);

Add curve

Line

  • Add line object
    1. Create line object
      var curve = new Phaser.Curves.Line({x: x0, y: y0}, {x: x1, y: y1});
      
      or
      var curve = new Phaser.Curves.Line([x0, y0, x1, y1]);
      
    2. Add to path
      path.add(curve);
      
  • Add line started from previous end point to next point
    path.lineTo(endX, endY);
    
    or
    path.lineTo(new Phaser.Math.Vector2({x, y}));
    

Properties:

  • curve.p0 : The first endpoint.
    • curve.p0.x, curve.p0.y
  • curve.p1 : The second endpoint.
    • curve.p1.x, curve.p1.y

Circle/ellipse/arc

  • Add circle/ellipse/arc object
    1. Create circle/ellipse/arc object
      • Circle
        var curve = new Phaser.Curves.Ellipse(x, y, radius);
        
      • Ellipse
        var curve = new Phaser.Curves.Ellipse(x, y, xRadius, yRadius);
        
      • Arc
        var curve = new Phaser.Curves.Ellipse(x, y, xRadius, yRadius, startAngle, endAngle, clockwise,     rotation);
        
    2. Add to path
      path.add(curve);
      
  • Add circle/ellipse/arc started from previous end point to next point
    • Circle
      path.circleTo(radius);
      
    • Ellipse
      path.ellipseTo(xRadius, yRadius);
      
    • Arc
      path.ellipseTo(xRadius, yRadius, startAngle, endAngle, clockwise, rotation);
      

Properties:

  • curve.p0 : Center point.
    • curve.p0.x, curve.p0.y
  • curve.xRadius, curve.yRadius : Horizontal/vertical radiuse.
  • curve.startAngle, curve.endAngle : Start/end angle, in degrees.
  • curve.clockwise : true if Clockwise, false if anti-clockwise.
  • curve.angle : Rotation, in degrees.
    • curve.rotation : Rotation, in radians.

Spline

  • Add spline object
    1. Create spline object
      var curve = new Phaser.Curves.Spline([
          p0,            // {x, y}, or [x, y]
          p1,            // {x, y}, or [x, y]
          // ...
      ]);
      
      or
      var curve = new Phaser.Curves.Spline([
          x0, y0,
          x1, y1,
          // ...
      ]);
      
    2. Add to path
      path.add(curve);
      
  • Add spline started from previous end point to next point
    var points = ;
    path.splineTo([
        p0,            // {x, y}, or [x, y]
        p1,            // {x, y}, or [x, y]
        // ...
    ]);
    
    or
    path.splineTo([
        x0, y0,
        x1, y1,
        // ...
    ]);
    
Append point
var point = curve.addPoint(x, y);

Quadratic bezier curve

  1. Create quadratic bezier curve object
    var curve = new Phaser.Curves.QuadraticBezier(startPoint, controlPoint, endPoint); // point: {x, y}
    
    or
    var points = [
        x0, y0,     // start point
        x1, y1,     // control point
        x2, y2      // end point
    ];
    var curve = new Phaser.Curves.QuadraticBezier(points);
    
  2. Add to path
    path.add(curve);
    

Add quadratic bezier curve started from previous end point to next point

path.quadraticBezierTo(endX, endY, controlX, controlY);
or
path.quadraticBezierTo(endPoint, controlPoint);  // point : Phaser.Math.Vector2

Cubic bezier curve

  1. Create quadratic bezier curve object
    var curve = new Phaser.Curves.CubicBezier(startPoint, controlPoint1, controlPoint2, endPoint); // point: {x, y}
    
    or
    var points = [
        x0, y0,     // start point
        x1, y1,     // control point1
        x2, y2,     // control point2
        x3, y3      // end point
    ];
    var curve = new Phaser.Curves.CubicBezier(points);
    
  2. Add to path
    path.add(curve);
    

Add cubic bezier curve started from previous end point to next point

path.cubicBezierTo(endX, endY, control1X, control1Y, control2X, control2Y);
or
path.cubicBezierTo(endPoint, controlPoint1, controlPoint2);  // point : Phaser.Math.Vector2

Move to point

path.moveTo(x, y);

Add curves from JSON

path.fromJSON(json);

Get curves

var curves = path.curves;

Draw on graphics

path.draw(graphics);
// path.draw(graphics, pointsTotal);
  • pointsTotal : The number of points to draw for each Curve.

or

curve.draw(graphics);
// curve.draw(graphics, pointsTotal);
  • pointsTotal : The resolution of the curve.

Point

  • Get point
    var out = path.getPoint(t);  // t: 0 ~ 1
    // var out = path.getPoint(t, out);  // modify out
    
    or
    var out = curve.getPoint(t);  // t: 0 ~ 1
    // var out = curve.getPoint(t, out);  // modify out
    
    Distance of path from start point to target point (out) might not linear with t.
  • Get random point
    var out = path.getRandomPoint();
    // var out = path.getRandomPoint(out);  // modify out
    
    or
    var out = curve.getRandomPoint();
    // var out = curve.getRandomPoint(out);  // modify out
    
  • Get n points
    • Path
      var points = path.getPoints(divisions);
      
      • divisions : The number of divisions per resolution per curve.
    • Curve
      var points = curve.getPoints(divisions);
      // var points = curve.getPoints(divisions, undefined, out);
      
      or
      var points = curve.getPoints(undefined, stepRate);
      // var points = curve.getPoints(undefined, stepRate, out);
      
      • divisions : The number of divisions in this curve.
        1. divisions, if divisions > 0, else
        2. this.getLength / stepRate, if stepRate > 0, else
        3. defaultDivisions
      • points : Return 1 + divisions points.
  • Get (n+1) points equally spaced out along the curve
    var points = path.getSpacedPoints(n);
    
    or
    var points = curve.getSpacedPoints(n);
    // var points = curve.getSpacedPoints(undefined, stepRate);
    // var points = curve.getSpacedPoints(divisions, stepRate, out);
    
  • Get points spaced out n distance pixels apart
    var points = curve.getDistancePoints(n)
    
    The smaller the distance, the larger the array will be.
    Path object does NOT support this feature yet.
  • Get start point
    var out = path.getStartPoint();
    // var out = path.getStartPoint(out);  // modify out
    
    or
    var out = curve.getStartPoint();
    // var out = curve.getStartPoint(out);  // modify out
    
  • Get end point
    var out = path.getEndPoint();
    // var out = path.getEndPoint(out);  // modify out
    
    or
    var out = curve.getEndPoint();
    // var out = curve.getEndPoint(out);  // modify out
    
  • Get t (0~1) from distance
    var t = curve.getTFromDistance(d);
    
    Path object does NOT support this feature yet.
  • Get tangent
    var out = path.getTangent(t);  // t: 0~1
    // var out = path.getTangent(t, out);  // modify out
    
    or
    var out = curve.getTangent(t);  // t: 0~1
    // var out = curve.getTangent(t, out);  // modify out
    

Length of path

var l = path.getLength();
or
var l = curve.getLength();

Length of path/curve will be cached.

Update length

path.updateArcLengths();
or
curve.updateArcLengths();

Curves to JSON

var json = path.toJSON();
or
var json = curve.toJSON();

Bounds

Get bounds

var out = path.getBounds();    // accuracy = 16
// var out = path.getBounds(out);
// var out = path.getBounds(out, accuracy);
or
var out = curve.getBounds();    // accuracy = 16
// var out = curve.getBounds(out);
// var out = curve.getBounds(out, accuracy);

Destroy

path.destroy();