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  • Special cases
  • Drawing functions, zoom and automatic scrollbars
  • Pattern and PHP
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Stored procedures
Removes the image from memory. For a drawing performed in an Image control, the current drawing is destroyed.

Remark: The call to dEndDrawing is optional. The resources are automatically deleted when the window or the page is closed.
// Destroy the drawing found in the "IMG_Drawing" control
<Element>: Optional control name or optional Image, WDPic or picLayer variable
Element to use:
  • Name of an Image control to erase.
  • Name of an Image variable.
    PHP This type of variable is not available.
If this parameter is not specified:
  • all the Image controls found in the current window will be erased.
  • all the images will be removed from memory.

Special cases

  • dStartDrawing must be called before using the drawing functions. dStartDrawing is used to define the element (Image control or Image variable) onto which the drawing functions will be applied.
  • For an Image control:
    • The drawing functions operate on a copy ("bitmap") of the image. You can use the drawing functions of Windows (via API or CallDLL32) but these Windows functions must use the DC (Device Context) returned by dStartDrawing.
    • dEndDrawing and dStartDrawing must not be called in the same process.
      The drawing will not be displayed if dEndDrawing and dStartDrawing are called in the same process: it will be automatically erased.
User code (UMC)

Drawing functions, zoom and automatic scrollbars

The "Automatic scrollbars and zoom" option available on Image controls is incompatible with dStartDrawing. If this option is used on the Image control, dStartDrawing freezes the image in the control. The zoom and the scrollbars are also frozen. The standard behavior is restored during the call to dEndDrawing.

Pattern and PHP

In PHP, the drawing functions are based on the graphic library GD. This library is commonly used by the PHP hosting companies and therefore it is always enabled. The version of the GD library must be version 2.0.28 (or later). This library can be downloaded from the PHP site.
To enable (if necessary) this library locally, the following elements are required:
  • PHP installed.
  • the PHP.INI file found in the Windows directory must contain the following line: "extension=php_gd2.dll" (instead of ";extension=php_gd2.dll").
  • the php_gd2.dll file must exist in the directory of PHP extensions. This directory is defined in the PHP.INI file by the "extension_dir" variable.
Related Examples:
WD Magnifier Complete examples (WINDEV): WD Magnifier
[ + ] This example enables you to zoom part of the screen with a magnifier.
The maximum zoom value is set to 8.
Summary of the example supplied with WINDEV:
The WLanguge function named dCopyBlt() and the WLanguage property named ..Opacity allow you to perform a capture of the Windows desktop at the location of a window without this window appearing in the screen shot.
This example uses this tip to zoom the part of the screen found below the magnifier.
Component: wd260pnt.dll
Minimum version required
  • Version 9
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