StreamGeometryContext.ArcTo Method

Definition

Draws an arc to the specified point.

C#
public abstract void ArcTo(System.Windows.Point point, System.Windows.Size size, double rotationAngle, bool isLargeArc, System.Windows.Media.SweepDirection sweepDirection, bool isStroked, bool isSmoothJoin);

Parameters

point
Point

The destination point for the end of the arc.

size
Size

The radii (half the width and half the height) of an oval whose perimeter is used to draw the angle. If the oval is very rounded in all directions, the arc will be rounded, if it is nearly flat, so will the arc. For example, a very large width and height would represent a very large oval, which would give a slight curvature for the angle.

rotationAngle
Double

The rotation angle of the oval that specifies the curve. The curvature of the arc can be rotated with this parameter.

isLargeArc
Boolean

true to draw the arc greater than 180 degrees; otherwise, false.

sweepDirection
SweepDirection

A value that indicates whether the arc is drawn in the Clockwise or Counterclockwise direction.

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.

Examples

The following example shows how to draw an arc using the ArcTo method.

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

namespace SDKSample
{
    public partial class StreamGeometryArcToExample : Page
    {
        public StreamGeometryArcToExample()
        {
            // Create a path to draw a geometry with.
            Path myPath = new Path();
            myPath.Stroke = Brushes.Black;
            myPath.StrokeThickness = 1;

            // 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 an arc. Draw the arc from the begin point to 200,100 with the specified parameters.
                ctx.ArcTo(new Point(200, 100), new Size(100, 50), 45 /* rotation angle */, true /* is large arc */, 
                          SweepDirection.Counterclockwise, true /* is stroked */, false /* is smooth join */);
            }

            // Freeze the geometry (make it unmodifiable)
            // for additional performance benefits.
            geometry.Freeze();
            
            // specify the shape (arc) 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;
        }
    }
}

Remarks

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

Product Versions
.NET Framework 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
Windows Desktop 3.0, 3.1, 5, 6, 7, 8, 9, 10

See also