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ZoomAtPoint Method

Summary

Zooms the image display at the specified point with the specified scale factor.

Syntax

C++

public virtual void ZoomAtPoint( 
   Point pt, 
   double scaleFactor 
)

  
Public Overridable Sub ZoomAtPoint( _ 
   ByVal pt As Point, _ 
   ByVal scaleFactor As Double _ 
)

public: 
virtual void ZoomAtPoint(  
   Point pt, 
   double scaleFactor 
)

Parameters

pt
The point at which to zoom the image display, in client coordinates.

scaleFactor
Scale factor to use. A value greater than 1 will zoom in the image and a value less than 1 will zoom out the image. Must be a value greater than 0.

Remarks

If the value of scaleFactor was anything other than the default value of 1, then this method will zooms in (if the value is greater than 1) or zooms out (if the value is less than 0) the image as well around the point specified by pt.

Example

This example shows to zoom the viewer around the point when the user clicks on the image.

using Leadtools.WinForms; 
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Drawing; 
 
private static void ZoomAtPointExample(RasterImageViewer viewer) 
{ 
   // Subscribe to the viewer click event 
   viewer.MouseClick += viewer_MouseClick; 
} 
 
private static void viewer_MouseClick(object sender, MouseEventArgs e) 
{ 
   // Zoom in twice around the mouse coordinates 
   RasterImageViewer viewer = sender as RasterImageViewer; 
   viewer.ZoomAtPoint(new Point(e.X, e.Y), 2.0); 
}

Imports Leadtools.WinForms 
Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Color 
Imports Leadtools.Drawing 
 
Private Shared Sub ZoomAtPointExample(ByVal viewer As RasterImageViewer) 
   ' Subscribe to the viewer click event 
   AddHandler viewer.MouseClick, AddressOf viewer_MouseClick 
End Sub 
 
Private Shared Sub viewer_MouseClick(ByVal sender As Object, ByVal e As MouseEventArgs) 
   ' Zoom in twice around the mouse coordinates 
   Dim viewer As RasterImageViewer = CType(sender, RasterImageViewer) 
   viewer.ZoomAtPoint(New Point(e.X, e.Y), 2.0) 
End Sub

Requirements

Target Platforms

Reference

RasterImageViewer Class

RasterImageViewer Members

Help Version 19.0.2017.10.27

Leadtools.WinForms Assembly

Introduction

Getting Started

Namespaces

Leadtools.WinForms Namespace

Assemblies