dEndDrawing (Function)

ONLINE HELP
WINDEV, WEBDEV AND WINDEV MOBILE

Version:

Home | Sign in | English

This content has been translated automatically. Click here to view the French version.

Help / WLanguage / WLanguage functions / Controls, pages and windows / Drawing functions

Special cases
Drawing functions, zoom and automatic scrollbars
Drawing in PHP
Drawing in Browser code

WINDEV

WEBDEV

WINDEV Mobile

Others

See also

dEndDrawing (Function)

In french: dFinDessin

Deletes all the drawings made since the last call to dStartDrawing.

In the case of an Image control, the current drawing is deleted.

In the case of a variable, the memory used is released.

Note: Calling the dEndDrawing function is optional.. The resources are automatically released when the window or page is closed.

Caution: Using this function under Linux requires a specific configuration.. For more details, see The drawings.

Example

// Destruction de l'image présente dans le champ Image "IMG_Dessin"
dEndDrawing(IMG_Dessin)

Syntax

dEndDrawing([<Element>])

<Element>: Optional control name or optional Image, WDPic or picLayer variable

Element to use:
Name of an Image control to erase.
Name of a variable of type Image.
This type of variable is not available.
Name of a variable of type WDPic. Only the background layer will be handled.
Name of a variable of type picLayer.
If this parameter is not specified:
all the Image controls in the current window will be deleted.
all the images will be removed from memory.

Remarks

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.
  If the function dEndDrawing is called in the same process as the dStartDrawing function, the drawing will not appear: it will be automatically deleted.

Drawing functions, zoom and automatic scrollbars

The "Automatic scrollbars and zoom" option, available for Image controls, is not compatible 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 when dEndDrawing is called.

Drawing in 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.

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.

Attention: 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 display the project description window, under the "Project" pane, in the "Project" group, click on "Description".

Special case: Drawing in the browser of an Android phone: Browser drawing functions are only available in Android version 3 and higher..

Related Examples:

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: wd300pnt.dll