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  • Use in prefix syntax
  • Characteristics of drawings in the browser
  • Drawing in Browser code
  • Drawing with opacity
  • Drawing in PHP
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Stored procedures
Indicates that the drawing functions that will be used are intended for a variable of type Image.
Remark: <Image variable>.StartDrawing initializes all the parameters required to create a drawing for a given element.
Linux Caution: A specific configuration is required to use this function in Linux. For more details, see The drawings.
Example
MyImage is Image = "Test.gif"
// Start of drawing
ResDrawing = MyImage.StartDrawing()
// Drawings in MyImage
...
// End of drawings in MyImage
IMG_MyDrawing = MyImage
MyImage is Image = "Test.gif"
MyImage.StartDrawing()
MyImage.Font("Arial", 12, iNormal, 0)
MyImage.DrawText(4, 0, "I'm writing in an Image variable!")
IMG_MyDrawing = MyImage
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.
Universal Windows 10 AppAndroidJava 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.
Universal Windows 10 AppAndroidJava 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 QueriesUniversal Windows 10 AppAndroidJavaUser 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: <Image variable>.PixelOpacity is used to find out the opacity of a point.
  3. Use <Image variable>.SavePNG to save your drawing in PNG format with alpha channel (opacity).
Limit: In "Management of opacity" mode, <Image variable>.DrawText is limited to the use of True Type 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: wd280pnt.dll
Minimum version required
  • Version 24
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Last update: 06/21/2023

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