MagGlassExt2 event (ILEADRasterView)

Visual Basic Example

Visual C++ 5.0 example

Delphi 4 example

C++ Builder example

 

Syntax

void MagGlassExt2 (long nMaskPlaneStart, long nMaskPlaneEnd, VARIANT vMaskPlane);

Overview

Refer to Using the Magnifying Glass

Remarks

This event is triggered for each WM_LBUTTONDOWN, WM_MOUSEMOVE and WM_LBUTTONUP message received by the window to which the magnifying glass is attached. This event is triggered only if the EnableMagGlassEvent property is set to TRUE.

After calling the StartMagGlass method, LEADTOOLS will monitor the window's messages, looking for mouse messages, and processing them by displaying a "Magnifying Glass". If the MagGlassExt2 event has been enabled by setting the EnableMagGlassEvent property to TRUE, information about the non-updated parts of the bitmap can be obtained from the vMaskPlane parameter passed to this event. This event receives information when the left mouse button is pressed or released and when the mouse is moved while the left mouse button is pressed. This information can be used with LEADTOOLS Internet functionality, available only in the Multimedia/Internet toolkits, to get pixel values for the non-updated parts of the bitmap. Once this information is received, it can be passed to the UpdateMagGlass2 method to update the Magnifying Glass's zoomed display area.

If the MagGlassExt2 event has been enabled by setting the EnableMagGlassEvent property to TRUE, the UpdateMagGlass2 method must be called in order to paint the zoomed image in the Magnifying Glass display area.

See Also

Elements:

StartMagGlass method, StopMagGlass method, UpdateMagGlass2 method, EnableMagGlassEvent property

Topics:

Raster Images: Displaying Images