# Isoparamatric Curve
Used to create curves on a surface that are aligned with the isoparametric direction.
How to use：
Click the "Isoparametric Curve" command in the "3D Curve" dropdown menu.
Select a surface.
Specify a point on the surface through which the isoparametric curve will pass.
Set the options and parameters as needed.
Click OK to complete the curve creation.
Dialog Box Control Instructions：
Surface: Select the surface on which to create the isoparametric curve.
Through Point: Click on the surface to specify the point that the isoparametric curve will pass through. The direction of the curve is influenced by the mouse movement when specifying this point.
Parameter Type: Controls the type of parameter for the through point's position.
Absolute: The parameter of the through point relative to the absolute origin.
Relative: The parameter of the through point relative to the relative origin. The relative origin defaults to coinciding with the absolute origin. Click the "Reset Origin" button to move the relative origin to the current through point.
Actual Length: Available only when the parameter type is "Relative"; displays the actual distance between the through point and the relative origin.
Direction: Check this option to pick a line to define the UV direction of the surface.
Swap UV Direction: Check this option to swap the UV directions of the surface.
Select Exchanged Face: For a surface composed of multiple patches, select a patch here to change the extension direction of the curve on that patch.
