transform_extrude
The <transform_extrude> operator “extrudes” from one 2d shape to another into a solid. It requires exactly 2 contained 2d shape operands. The first 2d shape contained is the bottom profile. The second 2d shape is the top profile, it must be lifted from the xy plane using a transformation.
Example using transform_extrude to make a transition solid from a rounded square profile to a circle profile:
<?xml version="1.0" encoding="utf-8"?>
<xcsg version="1.0" secant_tolerance="0.001">
<transform_extrude>
<offset2d delta="10" round="true" chamfer="false">
<square size="60" center="true"/>
</offset2d>
<circle r="30">
<tmatrix>
<trow c0="1" c1="0" c2="0" c3="0"/>
<trow c0="0" c1="1" c2="0" c3="0"/>
<trow c0="0" c1="0" c2="1" c3="50"/>
<trow c0="0" c1="0" c2="0" c3="1"/>
</tmatrix>
</circle>
</transform_extrude>
</xcsg>