message: throw when trying to construct a circle from 3 linear points
diff: @@ -277,10 +277,18 @@ namespace MakerJs.paths {
  }
  //find intersection of slopes of perpendiculars
  - this.origin = point.fromSlopeIntersection(perpendiculars[0], perpendiculars[1]);
  + var origin = point.fromSlopeIntersection(perpendiculars[0], perpendiculars[1]);
  +
  + if (origin) {
  + this.origin = origin;
  //radius is distance to any of the 3 points
  this.radius = measure.pointDistance(this.origin, args[0]);
  +
  + } else {
  + throw 'invalid parameters - attempted to construct a circle from 3 points on a line: ' + JSON.stringify(args);
  + }
  +
  break;
  }
  }
  