Graphics.DrawBeziers Method

Definition

Namespace:

System.Drawing

Assembly:

System.Drawing.Common.dll

Draws a series of Bézier splines from an array of Point structures.

Overloads

DrawBeziers(Pen, Point[])	Draws a series of Bézier splines from an array of Point structures.
DrawBeziers(Pen, PointF[])	Draws a series of Bézier splines from an array of PointF structures.

DrawBeziers(Pen, Point[])

Draws a series of Bézier splines from an array of Point structures.

public:
 void DrawBeziers(System::Drawing::Pen ^ pen, cli::array <System::Drawing::Point> ^ points);

public void DrawBeziers (System.Drawing.Pen pen, System.Drawing.Point[] points);

member this.DrawBeziers : System.Drawing.Pen * System.Drawing.Point[] -> unit

Public Sub DrawBeziers (pen As Pen, points As Point())

Parameters

pen

Pen

Pen that determines the color, width, and style of the curve.

points

Point[]

Array of Point structures that represent the points that determine the curve. The number of points in the array should be a multiple of 3 plus 1, such as 4, 7, or 10.

Exceptions

ArgumentNullException

pen is null.

-or-

points is null.

Examples

The following code example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code performs the following actions:

• Creates a black pen.

• Creates the start, end, and two control points for a first curve and endpoint and two control points for a second curve.

• Draws the successive Bézier curves to the screen.

private:
   void DrawBeziersPoint( PaintEventArgs^ e )
   {
      // Create pen.
      Pen^ blackPen = gcnew Pen( Color::Black,3.0f );

      // Create points for curve.
      Point start = Point(100,100);
      Point control1 = Point(200,10);
      Point control2 = Point(350,50);
      Point end1 = Point(500,100);
      Point control3 = Point(600,150);
      Point control4 = Point(650,250);
      Point end2 = Point(500,300);
      array<Point>^ bezierPoints = {start,control1,control2,end1,control3,control4,end2};

      // Draw arc to screen.
      e->Graphics->DrawBeziers( blackPen, bezierPoints );
   }

private void DrawBeziersPoint(PaintEventArgs e)
{
    // Create pen.
    Pen blackPen = new Pen(Color.Black, 3);
             
    // Create points for curve.
    Point start = new Point(100, 100);
    Point control1 = new Point(200, 10);
    Point control2 = new Point(350, 50);
    Point end1 = new Point(500, 100);
    Point control3 = new Point(600, 150);
    Point control4 = new Point(650, 250);
    Point end2 = new Point(500, 300);
    Point[] bezierPoints =
             {
                 start, control1, control2, end1,
                 control3, control4, end2
             };
             
    // Draw arc to screen.
    e.Graphics.DrawBeziers(blackPen, bezierPoints);
}

Private Sub DrawBeziersPoint(ByVal e As PaintEventArgs)

    ' Create pen.
    Dim blackPen As New Pen(Color.Black, 3)

    ' Create points for curve.
    Dim start As New Point(100, 100)
    Dim control1 As New Point(200, 10)
    Dim control2 As New Point(350, 50)
    Dim end1 As New Point(500, 100)
    Dim control3 As New Point(600, 150)
    Dim control4 As New Point(650, 250)
    Dim end2 As New Point(500, 300)
    Dim bezierPoints As Point() = {start, control1, control2, _
    end1, control3, control4, end2}

    ' Draw arc to screen.
    e.Graphics.DrawBeziers(blackPen, bezierPoints)
End Sub

Remarks

The number of points in the array should be a multiple of 3 plus 1 because the first spline requires 4 points and any other splines require 3 points each. The first Bézier spline is drawn from the first point to the fourth point in the point array. The second and third points are control points that determine the shape of the curve. Each subsequent curve needs exactly three more points: two more control points and an ending point. The ending point of the previous curve is used as the starting point for each additional curve.

DrawBeziers(Pen, PointF[])

Draws a series of Bézier splines from an array of PointF structures.

public:
 void DrawBeziers(System::Drawing::Pen ^ pen, cli::array <System::Drawing::PointF> ^ points);

public void DrawBeziers (System.Drawing.Pen pen, System.Drawing.PointF[] points);

member this.DrawBeziers : System.Drawing.Pen * System.Drawing.PointF[] -> unit

Public Sub DrawBeziers (pen As Pen, points As PointF())

Parameters

pen

Pen

Pen that determines the color, width, and style of the curve.

points

PointF[]

Array of PointF structures that represent the points that determine the curve. The number of points in the array should be a multiple of 3 plus 1, such as 4, 7, or 10.

Exceptions

ArgumentNullException

pen is null.

-or-

points is null.

Examples

The following code example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code performs the following actions:

• Creates a black pen.

• Creates the start, end, and two control points for a first curve and endpoint and two control points for a second curve.

• Draws the successive Bézier curves to the screen.

private:
   void DrawBeziersPointF( PaintEventArgs^ e )
   {
      // Create pen.
      Pen^ blackPen = gcnew Pen( Color::Black,3.0f );

      // Create points for curve.
      PointF start = PointF(100.0F,100.0F);
      PointF control1 = PointF(200.0F,10.0F);
      PointF control2 = PointF(350.0F,50.0F);
      PointF end1 = PointF(500.0F,100.0F);
      PointF control3 = PointF(600.0F,150.0F);
      PointF control4 = PointF(650.0F,250.0F);
      PointF end2 = PointF(500.0F,300.0F);
      array<PointF>^ bezierPoints = {start,control1,control2,end1,control3,control4,end2};

      // Draw arc to screen.
      e->Graphics->DrawBeziers( blackPen, bezierPoints );
   }

private void DrawBeziersPointF(PaintEventArgs e)
{
    // Create pen.
    Pen blackPen = new Pen(Color.Black, 3);
             
    // Create points for curve.
    PointF start = new PointF(100.0F, 100.0F);
    PointF control1 = new PointF(200.0F, 10.0F);
    PointF control2 = new PointF(350.0F, 50.0F);
    PointF end1 = new PointF(500.0F, 100.0F);
    PointF control3 = new PointF(600.0F, 150.0F);
    PointF control4 = new PointF(650.0F, 250.0F);
    PointF end2 = new PointF(500.0F, 300.0F);
    PointF[] bezierPoints = { start, control1, control2, end1,
         control3, control4, end2 };      
                 
    // Draw arc to screen.
    e.Graphics.DrawBeziers(blackPen, bezierPoints);
}

Private Sub DrawBeziersPointF(ByVal e As PaintEventArgs)

    ' Create pen.
    Dim blackPen As New Pen(Color.Black, 3)

    ' Create points for curve.
    Dim start As New PointF(100.0F, 100.0F)
    Dim control1 As New PointF(200.0F, 10.0F)
    Dim control2 As New PointF(350.0F, 50.0F)
    Dim end1 As New PointF(500.0F, 100.0F)
    Dim control3 As New PointF(600.0F, 150.0F)
    Dim control4 As New PointF(650.0F, 250.0F)
    Dim end2 As New PointF(500.0F, 300.0F)
    Dim bezierPoints As PointF() = {start, control1, control2, _
    end1, control3, control4, end2}

    ' Draw arc to screen.
    e.Graphics.DrawBeziers(blackPen, bezierPoints)
End Sub

Remarks

The number of points in the array should be a multiple of 3 plus 1 because the first spline requires 4 points and any other splines require 3 points each. The first Bézier curve is drawn from the first point to the fourth point in the point array. The second and third points are control points that determine the shape of the curve. Each subsequent curve needs exactly three more points: two more control points and an ending point. The ending point of the previous curve is used as the starting point for each additional curve.