Drawing Cardinal Splines Using GDI+

A cardinal spline is a sequence of individual curves joined to form a larger curve. The spline is specified by an array of points and a tension parameter.

The following illustration shows a set of points and a cardinal spline that passes through each point in the set.

Drawing a Cardinal Spline

To draw a cardinal spline, you need a Graphics object, a Pen object, and the third parameter is a tension.

Call DrawCurve method to draw a cardinal spline. The Pen object, array of point, and tension are passed as arguments.

The following is the syntax of DrawCurve method:

The following code example demonstrates how to draw a cardinal spline:

Dim myImage As New Bitmap(300, 300, Imaging.PixelFormat.Format32bppRgb) Dim myGraphics As Graphics = Graphics.FromImage(myImage) myGraphics.Clear(Color.White) Dim myPen As New Pen(Color.Blue, 2) 'create Point object Dim myPointArray As Point() = {New Point(0, 0), New Point(50, 30), New Point(30, 60)} 'draw a cardinal spline myGraphics.DrawCurve(myPen, myPointArray, 1) myImage.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)