Smoothing a hand-drawn curve

Question

I\'ve got a program that allows users to draw curves. But these curves don\'t look nice - they look wobbly and hand-drawn.

So I want an algorithm that will automatic

Answer 1

For Silverlight users of Kris' answer, Point is hobbled and Vector doesn't exist. This is a minimal Vector class that supports the code:

public class Vector
{
   public double X { get; set; }
   public double Y { get; set; }
   public Vector(double x=0, double y=0)
   {
      X = x;
      Y = y;
   }

   public static implicit operator Vector(Point b)
   {
      return new Vector(b.X, b.Y);
   }

   public static Point operator *(Vector left, double right)
   {
      return new Point(left.X * right, left.Y * right);
   }
   public static Vector operator -(Vector left, Point right)
   {
      return new Vector(left.X - right.X, left.Y - right.Y);
   }

   internal void Negate()
   {
      X = -X;
      Y = -Y;
   }

   internal void Normalize()
   {
      double factor = 1.0 / Math.Sqrt(LengthSquared);
      X *= factor;
      Y *= factor;
   }

   public double LengthSquared { get { return X * X + Y * Y; } }
}

Also had to address use of Length and +,- operators. I chose to just add functions to the FitCurves class, and rewrite their usages where the compiler complained.

  public static double Length(Point a, Point b)
  {
     double x = a.X-b.X;
     double y = a.Y-b.Y;
     return Math.Sqrt(x*x+y*y);
  }

  public static Point Add(Point a, Point b)
  {
     return new Point(a.X + b.X, a.Y + b.Y);
  }

  public static Point Subtract(Point a, Point b)
  {
     return new Point(a.X - b.X, a.Y - b.Y);
  }