code: function(_p){
  		var v1 = _p.sub(this.a).normalize(),
  			v2 = _p.sub(this.b).normalize(),
  			v3 = _p.sub(this.c).normalize(),
  			totalAngles = Math.acos(v1.dot(v2));
  			totalAngles += Math.acos(v2.dot(v3));
  			totalAngles += Math.acos(v3.dot(v1));
  			return (mathUtils.abs(totalAngles- mathUtils.TWO_PI) <= 0.01);
       }
docs: Checks if point vector is inside the triangle created by the points a, b
  and c. These points will create a plane and the point checked will have
  to be on this plane in the region between a,b,c.
  
  Note: The triangle must be defined in clockwise order a,b,c
  
  @return true, if point is in triangle.