StreamGeometryContext.PolyBezierTo Método

Definição

Namespace:

System.Windows.Media

Assembly:

PresentationCore.dll

Desenha uma ou mais curvas de Bézier conectadas.

public:
 abstract void PolyBezierTo(System::Collections::Generic::IList<System::Windows::Point> ^ points, bool isStroked, bool isSmoothJoin);

public abstract void PolyBezierTo (System.Collections.Generic.IList<System.Windows.Point> points, bool isStroked, bool isSmoothJoin);

abstract member PolyBezierTo : System.Collections.Generic.IList<System.Windows.Point> * bool * bool -> unit

Public MustOverride Sub PolyBezierTo (points As IList(Of Point), isStroked As Boolean, isSmoothJoin As Boolean)

Parâmetros

points

IList<Point>

A lista de pontos que especificam os pontos de controle e os pontos de destino para uma ou mais curvas de Bézier. O número de pontos nesta lista deve ser um múltiplo de três.

isStroked

Boolean

true para deixar o segmento tracejado quando uma Pen for usada para renderizar o segmento, caso contrário, false.

isSmoothJoin

Boolean

true para tratar a junção entre esse segmento e o segmento anterior como um canto quando traçados com um Pen; caso contrário, false.

Exceções

InvalidOperationException

Foi feita uma tentativa para adicionar um segmento sem iniciar uma figura ao chamar o método BeginFigure(Point, Boolean, Boolean).

Exemplos

O exemplo a seguir mostra como desenhar várias curvas de Bezier conectadas usando o PolyBezierTo método .

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

namespace SDKSample
{
    public partial class StreamGeometryPolyBezierToExample : Page
    {
        public StreamGeometryPolyBezierToExample()
        {
            // 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 a collection of Point structures that will be used with the PolyBezierTo 
                // Method to create the Bezier curve.
                List<Point> pointList = new List<Point>();

                // First Bezier curve is specified with these three points.

                // First control point for first Bezier curve.
                pointList.Add(new Point(100,0));

                // Second control point for first Bezier curve.
                pointList.Add(new Point(200, 200));

                // Destination point for first Bezier curve.
                pointList.Add(new Point(300, 100));

                // Second Bezier curve is specified with these three points.

                // First control point for second Bezier curve.
                pointList.Add(new Point(400, 0));

                // Second control point for second Bezier curve.
                pointList.Add(new Point(500, 200));

                // Destination point for second Bezier curve.
                pointList.Add(new Point(600, 100));

                // Create a Bezier curve using the collection of Point Structures.
                ctx.PolyBezierTo(pointList, true /* is stroked */, false /* is smooth join */);
            }

            // 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
Imports System.Collections.Generic

Namespace SDKSample
    Partial Public Class StreamGeometryPolyBezierToExample
        Inherits Page
        Public Sub New()
            ' Create a path to draw a geometry with.
            Dim myPath As New Path()
            myPath.Stroke = Brushes.Black
            myPath.StrokeThickness = 1

            ' 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 collection of Point structures that will be used with the PolyBezierTo 
                ' Method to create the Bezier curve.
                Dim pointList As New List(Of Point)()

                ' First Bezier curve is specified with these three points.

                ' First control point for first Bezier curve.
                pointList.Add(New Point(100,0))

                ' Second control point for first Bezier curve.
                pointList.Add(New Point(200, 200))

                ' Destination point for first Bezier curve.
                pointList.Add(New Point(300, 100))

                ' Second Bezier curve is specified with these three points.

                ' First control point for second Bezier curve.
                pointList.Add(New Point(400, 0))

                ' Second control point for second Bezier curve.
                pointList.Add(New Point(500, 200))

                ' Destination point for second Bezier curve.
                pointList.Add(New Point(600, 100))

                ' Create a Bezier curve using the collection of Point Structures.
                ctx.PolyBezierTo(pointList, True, False) ' is smooth join  -  is stroked 

            End Using

            ' 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

Comentários

O primeiro ponto em points especifica o primeiro ponto de controle, o próximo especifica o segundo ponto de controle, o terceiro ponto especifica o ponto final, o próximo ponto especifica o primeiro ponto de controle da próxima curva e assim por diante.

Esse método usa o ponto final do segmento anterior como ponto de partida. Se esse for o primeiro segmento em uma figura, ele usará o ponto especificado pelo BeginFigure método como seu ponto de partida.

Um StreamGeometry não pode ser serializado se contiver um Transform ou qualquer segmento não acarinhado ou não preenchido.

Confira também

• ArcTo(Point, Size, Double, Boolean, SweepDirection, Boolean, Boolean)
• BezierTo(Point, Point, Point, Boolean, Boolean)
• QuadraticBezierTo(Point, Point, Boolean, Boolean)
• PolyQuadraticBezierTo(IList<Point>, Boolean, Boolean)