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4D v14

SVG_Filter_Blend


SVG_Filter_Blend ( filterRef ; picture ; backgroundPict {; mode {; name}} ) -> Function result

Parameter	Type	Description
filterRef	SVG_Ref	Reference of filter
picture	String	Picture source
backgroundPict	String	Background picture source
mode	String	Mixing mode
name	String	Target of filter primitive
Function result	SVG_Ref	Reference of primitive

Description

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

This filter is made up of two sources, backgroundPict and picture, with the help of the mixing modes currently used by the imaging software.

The optional mode parameter can be used to set the combination mode of the pixels used for the blend (see the specification). Its value must be: "normal" (default value), "multiply", "screen", "darken" or "lighten".

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 "blend" filter and assign to the one on the right. This filter is a combination of the "offset" and "blur" filters:

 $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

 $filter:=SVG_Define_filter($root2;"MyShadow")

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

 If($vGraph)

    $ref1:=SVG_Filter_Blur($filter;2;"sourceGraphic";"blurResult") //"blurResult" will be used as the "input" of the offset filter

 Else

    $ref1:=SVG_Filter_Blur($filter;2;"sourceAlpha";"blurResult") //"blurResult" will be used as the "input" of the offset filter

 End if

  //Adding offset filter

 $ref2:=SVG_Filter_Offset($filter;5;5;"blurResult";"alphaBlurOffset")

  //Adding blend filter

 $ref3:=SVG_Filter_Blend($filter;"sourceGraphic";"alphaBlurOffset";"normal";"finalFilter";)

 

 $rect2:=SVG_New_rect($root2;10;10;380;100;0;0;"darkblue";"white";1)

 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;"MyShadow") //apply final filter

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

Result (blur input filter = sourceGraphic):

Result (blur input filter = sourceAlpha):