IImageTileSource.GetImage(Int32, Int32, Int32, Size) Method

Returns an image by the specified indices at a given map control zoom level.

Namespace: DevExpress.XtraMap

Assembly: DevExpress.XtraMap.v19.2.dll

Declaration

C#

Image GetImage(
    int x,
    int y,
    int level,
    Size size
)

VB.NET

Function GetImage(
    x As Integer,
    y As Integer,
    level As Integer,
    size As Size
) As Image

Parameters

Name	Type	Description
x	Int32	The tile x-index.
y	Int32	The tile y-index.
level	Int32	The map control’s zoom level.
size	Size	The tile size.

Returns

Type	Description
Image	An image that represents a map tile.

Example

This example shows how to use an ImageTileDataProvider instance to generate map tiles.

• Create an ImageTileDataProvider object and assign it to the ImageLayer.DataProvider property.
• Develop a class that inherits the IImageTileSource interface and represents a tile generator. This generator creates a bitmap for each tile based on its indices.
• Implement the interface’s IImageTileSource.GetImage method.
• Assign an instance of the class you developed to the ImageTileDataProvider.TileSource property.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-use-in-memory-image-tile-provider

C#

using DevExpress.XtraMap;
using System;
using System.Drawing;
using System.Windows.Forms;

namespace InMemoryTileProvider {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e) {
            ImageTileDataProvider tileDataProvider = new ImageTileDataProvider();
            tileDataProvider.TileSource = new SimpleTileGenerator();
            this.imageLayer1.DataProvider = tileDataProvider;
        }
        public class SimpleTileGenerator : IImageTileSource {
            readonly Font font = new Font("Arial", 10);
            Random rnd = new Random();
            public bool CanDisposeSourceImage => true;
            public string Name => nameof(SimpleTileGenerator);
            public Image GetImage(int x, int y, int level, Size size) {
                Bitmap bitmap = new Bitmap(size.Width, size.Height);
                using (Graphics gr = Graphics.FromImage(bitmap)) {
                    gr.Clear(Color.FromArgb(128, rnd.Next(255),
                            rnd.Next(255), rnd.Next(255)));
                    gr.DrawString(string.Format("{0} {1} {2}", x, y, level),
                           font, Brushes.Black, new PointF(5, 5));
                }
                return bitmap;
            }
        }
    }
}

VB.NET

Imports DevExpress.XtraMap
Imports System
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Linq
Imports System.Text
Imports System.Threading.Tasks
Imports System.Windows.Forms

Namespace InMemoryTileProvider
    Partial Public Class Form1
        Inherits Form

        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
            Dim tileDataProvider As New ImageTileDataProvider()
            tileDataProvider.TileSource = New SimpleTileGenerator()
            Me.imageLayer1.DataProvider = tileDataProvider
        End Sub

        Public Class SimpleTileGenerator
            Implements IImageTileSource

            Private ReadOnly font As New Font("Arial", 10)
            Private rnd As New Random()
            Public ReadOnly Property CanDisposeSourceImage() As Boolean
                Get
                    Return True
                End Get
            End Property
            Public ReadOnly Property Name() As String
                Get
                    Return NameOf(SimpleTileGenerator)
                End Get
            End Property

            Public Function GetImage(ByVal x As Integer, ByVal y As Integer, ByVal level As Integer, ByVal size As Size) As Image
                Dim bitmap As New Bitmap(size.Width, size.Height)
                Using gr As Graphics = Graphics.FromImage(bitmap)
                    gr.Clear(Color.FromArgb(128, rnd.Next(255), rnd.Next(255), rnd.Next(255)))
                    gr.DrawString(String.Format("{0} {1} {2}", x, y, level), font, Brushes.Black, New PointF(5, 5))
                End Using
                Return bitmap
            End Function
        End Class
    End Class
End Namespace