MapEditor.SimplifyItems(IEnumerable<MapItem>, Double) Method

Reduces the number of vertices that form the vector layer’s items with specified tolerance.

Namespace: DevExpress.Xpf.Map

Assembly: DevExpress.Xpf.Map.v24.2.dll

NuGet Package: DevExpress.Wpf.Map

Declaration

C#

public void SimplifyItems(
    IEnumerable<MapItem> items,
    double tolerance
)

VB.NET

Public Sub SimplifyItems(
    items As IEnumerable(Of MapItem),
    tolerance As Double
)

Parameters

Name	Type	Description
items	IEnumerable<MapItem>	The items to be simplified.
tolerance	Double	A percent of vertices that vector shapes contain after simplification. This value should be in the (0;100) range.

Example

This example demonstrates how to reduce the number of vertices that form vector layer items.

To do this, use the MapEditor.SimplifyItems(IEnumerable<MapItem>, Double) method.

The TrackBarEdit component is used to change the Tolerance parameter. The tolerance defines the percent of vertices that vector shapes should contain after simplification.

C#

using System;
using System.Windows;
namespace SvgDataAdapterSample {
    public partial class MainWindow : Window {        
        public MainWindow() {
            InitializeComponent();            
        }
        private void OnTrackbarEditValueChanged(object sender, DevExpress.Xpf.Editors.EditValueChangedEventArgs e) {
            double tolerance = Convert.ToDouble(toleranceTrackbar.EditValue);
            mapControl.MapEditor.SimplifyItems(adapter.DisplayItems, tolerance);
        }
    }
}

VB.NET

Imports System
Imports System.Windows
Namespace SvgDataAdapterSample   
    Public Class MainWindow
        Inherits Window

        Public Sub New()
            MyBase.New
            InitializeComponent
        End Sub

        Private Sub OnTrackbarEditValueChanged(ByVal sender As Object, ByVal e As DevExpress.Xpf.Editors.EditValueChangedEventArgs)
            Dim tolerance As Double = Convert.ToDouble(toleranceTrackbar.EditValue)
            mapControl.MapEditor.SimplifyItems(adapter.DisplayItems, tolerance)
        End Sub
    End Class
End Namespace

XAML

<Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxm="http://schemas.devexpress.com/winfx/2008/xaml/map" 
        xmlns:dxe="http://schemas.devexpress.com/winfx/2008/xaml/editors" 
        x:Class="SvgDataAdapterSample.MainWindow"
        xmlns:local="clr-namespace:SvgDataAdapterSample"
        Title="MainWindow" Height="360" Width="640">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="10*"/>
            <ColumnDefinition Width="3*"/>
        </Grid.ColumnDefinitions>
        <dxm:MapControl x:Name="mapControl" Grid.Column="0" Margin="10">
            <dxm:VectorLayer x:Name="vectorLayer">
                <dxm:SvgFileDataAdapter x:Name="adapter" FileUri="Data/countries.svg" />
            </dxm:VectorLayer>
            <dxm:MapControl.MapEditor>
                <dxm:MapEditor x:Name="mapEditor">
                    <dxm:MapEditor.EditorPanelOptions>
                        <dxm:MapEditorPanelOptions Visible="False"/>
                    </dxm:MapEditor.EditorPanelOptions>
                </dxm:MapEditor>
            </dxm:MapControl.MapEditor>
        </dxm:MapControl>
        <dxe:TrackBarEdit x:Name="toleranceTrackbar" Grid.Column="1" 
                          VerticalAlignment="Center" Margin="10" 
                          Maximum="100" Minimum="0" EditValue="100"
                          EditValueChanged="OnTrackbarEditValueChanged"/>
    </Grid>
</Window>