StreamGeometryContext.BezierTo(Point, Point, Point, Boolean, Boolean) Method

Reference

Definition

Namespace:: System.Windows.Media

Assembly:: PresentationCore.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Draws a Bezier curve to the specified point.

public:
 abstract void BezierTo(System::Windows::Point point1, System::Windows::Point point2, System::Windows::Point point3, bool isStroked, bool isSmoothJoin);

public abstract void BezierTo (System.Windows.Point point1, System.Windows.Point point2, System.Windows.Point point3, bool isStroked, bool isSmoothJoin);

abstract member BezierTo : System.Windows.Point * System.Windows.Point * System.Windows.Point * bool * bool -> unit

Public MustOverride Sub BezierTo (point1 As Point, point2 As Point, point3 As Point, isStroked As Boolean, isSmoothJoin As Boolean)

Parameters

point1: Point

The first control point used to specify the shape of the curve.

point2: Point

The second control point used to specify the shape of the curve.

point3: Point

The destination point for the end of the curve.

isStroked: Boolean

true to make the segment stroked when a Pen is used to render the segment; otherwise, false.

isSmoothJoin: Boolean

true to treat the join between this segment and the previous segment as a corner when stroked with a Pen; otherwise, false.

Exceptions

InvalidOperationException

An attempt was made to add a segment without starting a figure by calling the BeginFigure(Point, Boolean, Boolean) method.

Examples

The following example shows how to draw a Bezier curve using the BezierTo method.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;

namespace SDKSample
{
    public partial class StreamGeometryBezierToExample : Page
    {
        public StreamGeometryBezierToExample()
        {

            // Create a StreamGeometry to use to specify myPath.
            StreamGeometry geometry = new StreamGeometry();
            geometry.FillRule = FillRule.EvenOdd;

            // Open a StreamGeometryContext that can be used to describe this StreamGeometry 
            // object's contents.
            using (StreamGeometryContext ctx = geometry.Open())
            {
                // Set the begin point of the shape.
                ctx.BeginFigure(new Point(10, 100), true /* is filled */, false /* is closed */);

                // Create a Bezier curve using the 3 specifed points where the first two points
                // are control points and the last point is the destination point for the curve.
                ctx.BezierTo(new Point(100, 0), new Point(200,200), new Point(300,100), 
                             true /* is stroked */, false /* is smooth join */);
            }

            // Create a path to draw a geometry with.
            Path myPath = new Path();
            myPath.Stroke = Brushes.Black;
            myPath.StrokeThickness = 1;

            // Freeze the geometry (make it unmodifiable)
            // for additional performance benefits.
            geometry.Freeze();

            // specify the shape (Bezier Curve) of the path using the StreamGeometry.
            myPath.Data = geometry;

            // Add path shape to the UI.
            StackPanel mainPanel = new StackPanel();
            mainPanel.Children.Add(myPath);
            this.Content = mainPanel;
        }
    }
}


Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Shapes

Namespace SDKSample
    Partial Public Class StreamGeometryBezierToExample
        Inherits Page
        Public Sub New()

            ' Create a StreamGeometry to use to specify myPath.
            Dim geometry As New StreamGeometry()
            geometry.FillRule = FillRule.EvenOdd

            ' Open a StreamGeometryContext that can be used to describe this StreamGeometry 
            ' object's contents.
            Using ctx As StreamGeometryContext = geometry.Open()
                ' Set the begin point of the shape.
                ctx.BeginFigure(New Point(10, 100), True, False) ' is closed  -  is filled 

                ' Create a Bezier curve using the 3 specifed points where the first two points
                ' are control points and the last point is the destination point for the curve.
                ctx.BezierTo(New Point(100, 0), New Point(200,200), New Point(300,100), True, False) ' is smooth join  -  is stroked 

            End Using

            ' Create a path to draw a geometry with.
            Dim myPath As New Path()
            myPath.Stroke = Brushes.Black
            myPath.StrokeThickness = 1

            ' Freeze the geometry (make it unmodifiable)
            ' for additional performance benefits.
            geometry.Freeze()

            ' specify the shape (Bezier Curve) of the path using the StreamGeometry.
            myPath.Data = geometry

            ' Add path shape to the UI.
            Dim mainPanel As New StackPanel()
            mainPanel.Children.Add(myPath)
            Me.Content = mainPanel
        End Sub
    End Class
End Namespace

Remarks

A cubic Bezier curve is defined by a start point, end point, and two control points. The first control point determines the curvature of the first half of the segment, and the second control point determines the curvature of the second half of the segment.

This method uses the end point of the previous segment as its starting point. If this is the first segment in a figure, it uses the point specified by the BeginFigure method as its start point.

A StreamGeometry cannot be serialized if it contains a Transform or any non-stroked or unfilled segments.

Applies to

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