ONLINE HELP
 WINDEVWEBDEV AND WINDEV MOBILE

Help / WLanguage / WLanguage functions / Controls, pages and windows / Drawing functions
  • Use in prefix syntax
  • Characteristics of drawings in the browser
  • Drawing in Browser code
  • Drawing with opacity
  • Drawing in PHP
WINDEV
WindowsLinuxJavaReports and QueriesUser code (UMC)
WEBDEV
WindowsLinuxPHPWEBDEV - Browser code
WINDEV Mobile
AndroidAndroid Widget iPhone/iPadIOS WidgetApple WatchMac Catalyst
Others
Stored procedures
Indicates that the drawing functions that will be used are intended for a variable of type Image.
Remark: Function <Image variable>.StartDrawing initializes all parameters required to create (or continue) a drawing for a given element.
Linux Caution: Using this function under Linux requires a specific configuration.. For more details, see The drawings.
Example
MonImage is Image = "Test.gif"
// Début du dessin 
ResDessin = MonImage.DébutDessin()
// Dessins dans la variable MonImage
...
// Fin des dessins dans la variable MonImage
IMG_MonDessin = MonImage
MonImage is Image = "Test.gif"
MonImage.DébutDessin()
MonImage.Font("Arial", 12, iNormal, 0)
MonImage.DessineTexte(4, 0, "J'écris mon texte dans une variable Image!")
IMG_MonDessin = MonImage
Syntax
<Result> = <Image variable>.StartDrawing([<Options>])
<Result>: Boolean
  • True if the drawing was initialized,
  • False otherwise.
<Image variable>: Image variable
Name of the Image variable to be used.
<Options>: Optional Integer constant (or combination of constants)
Drawing options:
dGridlinesOpacityThe drawing is displayed over gridlines in order to highlight the transparent or semi-transparent sections of the drawing. The gridlines are not saved in the image.
AndroidJava This constant is not available.
dNoEraseDoes not erase the drawing in the variable.
dOnChartUsed to draw in a variable in which a chart has already been drawn. In this case, the chart drawing is not erased.
AndroidJava This constant is not available.
dWithOpacityAllows managing opacity in the different drawing functions used with the variable. Used for example to create a PNG drawing with an Alpha channel.

No drawing option is used if this parameter is not specified.
Remarks

Use in prefix syntax

<Image variable>.StartDrawing must be called before the other drawing functions. <Image variable>.StartDrawing makes it possible to define the drawing options used on the Image variable.
WINDEVWEBDEV - Server codeReports and QueriesAndroidJavaUser code (UMC)Ajax

Drawing with opacity

By creating a drawing that supports opacity, you can easily save PNG images with an Alpha channel.
To save a PNG drawing with an Alpha channel:
  1. Use the <Image variable>.StartDrawing function. This function is used to define, if necessary, the element onto which the drawing functions will be applied as well as the drawing mode. The dWithOpacity constant is used to indicate that the drawing will manage the opacity. The dGridlinesOpacity constant is used to display gridlines underneath the different drawing areas.
  2. Configure the opacity of your drawings with the following functions:
    <Image variable>.BackgroundDeclares the background color and its opacity for the next drawings.
    <Image variable>.DrawPointDeclares the color of the points and their opacity for the next drawings.
    <Image variable>.PenDeclares the color of the lines and their opacity for the next drawings.

    Remark: The <Image variable>.PixelOpacity function is used to determine the opacity of a point.
  3. Use <Image>.SavePNG to save your drawing in PNG format with alpha channel (opacity).
Limite: In "Opacity management" mode, the <Image variable>.DrawText function is limited to the use of TrueType fonts.
Related Examples:
The drawing functions Unit examples (WINDEV): The drawing functions
[ + ] Using the main drawing functions of WINDEV to:
- Initialize an Image control for drawing
- Draw simple shapes
- Write a text into a drawing
- Change the color in a drawing
Component: wd300pnt.dll
Minimum version required
  • Version 24
This page is also available for…
Comments
Click [Add] to post a comment

Last update: 09/26/2024

Send a report | Local help