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4D v14

SVG_Filter_Blur


SVG_Filter_Blur ( filterRef ; deviation {; input {; name}} ) -> Function result

Parameter	Type	Description
filterRef	SVG_Ref	Reference of filter
deviation	Real	Standard deviation for blur operation
input	String	Source of filter primitive
name	String	Target of filter primitive
Function result	SVG_Ref	Reference of primitive

Description

The SVG_Filter_Blur command sets a Gaussian blur for the filterRef filter and returns its reference. If filterRef is not a filter reference, an error is generated.

The deviation parameter can be used to set the standard deviation for the blur operation. If the number is an integer, the same deviation will be applied to the X and Y axes. If the number includes a decimal part, the integer part represents the deviation to be applied to the X axis and the decimal part represents the deviation to be applied to the Y axis.

The optional input parameter identifies the graphic source of the filter primitive. You can pass:

either "sourceGraphic", indicating that the graphic is the filter source (default),
or "sourceAlpha", which indicates that the alpha channel is the filter source.

The optional name parameter is the name, if any, assigned to the result of this filter primitive.

Note: Under Windows, this command requires the prior disabling of Direct2D (see the Direct2D disabled constant in the description of the SET DATABASE PARAMETER command).

Example

In a form, we display two identical SVG pictures then we create a "blur" filter and assign to the one on the right:

 $root:=SVG_New(400;400;"filters test") //definition of first (left) picture

 $rect:=SVG_New_rect($root;10;10;380;100;0;0;"darkblue";"white";1)

 SVG_SET_FILL_BRUSH($root;"orange")

 $textAreaRef:=SVG_New_textArea($root;"Hello World!";10;10;380;100;"arial";60;Normal;Align center)

 <>pict1:=SVG_Export_to_picture($root) //display first picture

 

 $root2:=SVG_New(400;400;"filters test") //definition of identical (right) picture

 

  //create filter

 $filter1:=SVG_Define_filter($root2;"blur")

  // filter definition

 $vGraph:=True //applied on graphic layer - pass False to apply to the alpha layer

 If($vGraph)

    SVG_Filter_Blur($filter1;Deviation{Deviation};"sourceGraphic")

 Else

    SVG_Filter_Blur($filter1;Deviation{Deviation};"sourceAlpha")

 End if

 

 $rect2:=SVG_New_rect($root2;10;10;380;100;0;0;"darkblue";"white";1) //definition of identical (right) picture

 SVG_SET_FILL_BRUSH($root2;"orange")

 $textAreaRef2:=SVG_New_textArea($root2;"Hello World!";10;10;380;100;"arial";60;Normal;Align center)

 

 SVG_SET_FILTER($textAreaRef2;"blur") //apply filter

 <>pict2:=SVG_Export_to_picture($root2) //display second picture

Result (input = sourceGraphic):

Result (input = sourceAlpha):