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  • Use in prefix syntax
  • Drawing functions, zoom and automatic scrollbars
  • Pattern and PHP
  • Drawing in Browser code
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Stored procedures
Deletes all the drawings made in the Image control since the last call to <Image>.StartDrawing.
Remark: The call to <Image>.EndDrawing is optional. The resources are automatically released when the window or page is closed.
Linux Caution: A specific configuration is required to use this function in Linux. For more details, see The drawings.
Example
// Destroy the drawing found in the "IMG_Drawing" control
IMG_Drawing.EndDrawing()
Syntax
<Image control>.EndDrawing()
<Image control>: Control name
Name of the Image control to be used.
Remarks

Use in prefix syntax

<Image>.StartDrawing must be called before using the drawing functions. <Image>.StartDrawing makes it possible to define the drawing options used on the Image control.
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 <Image>.StartDrawing.
  • <Image>.EndDrawing and <Image>.StartDrawing must not be called in the same process.
    The drawing will not be displayed if <Image>.EndDrawing and <Image>.StartDrawing are called in the same process: it will be automatically erased.
WINDEVUser code (UMC)

Drawing functions, zoom and automatic scrollbars

The "Automatic scrollbars and zoom" option, available for Image controls, is not compatible with <Image>.StartDrawing. If this option is used on the Image control, <Image>.StartDrawing freezes the image in the control. The zoom and the scrollbars are also frozen. The standard behavior is restored when <Image>.EndDrawing is called.
PHP

Pattern and PHP

In PHP, the drawing functions are based on the graphic library GD. This library is commonly used by the PHP hosting providers 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.
WEBDEV - Browser code

Drawing in Browser code

Some drawing functions are available in Browser code. The drawing functions in Browser code are based on the HTML 5 standard. More specifically, these functions are based on the "canvas" tag of HTML 5.
The drawing features in browser code are available for the recent browsers only (supporting the HTML 5 standard). To find out whether the drawing features are proposed by your browser, use DrawingAvailable.
Caution: To use the drawing functions with Internet Explorer 9, the project must include the reference to the DTD file. To do so, the HTML mode must be "HTML 4.01 Transitional + DTD". This option is available in the "Advanced" tab of the project description window.
Reminder: To open the project description window, go to the "Project" tab, "Project" group and click "Description".
Special case: Drawing in the browser of an Android phone: The browser drawing functions are only available starting with version 3 of Android.
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: wd290pnt.dll
Minimum version required
  • Version 24
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Last update: 01/18/2024

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