Iso Angle shader is a very useful tool for fine-tuning surface highlights. Iso Angles are simply bands/curves connecting the points on a surface, where the normal direction at those points make a constant angle to a defined vector. In automotive design, the Z vector (vertical direction) is usually taken as the reference, as it is perpendicular to the horizon plane. Alias and ICEM Surf users are quite familiar with such diagnostic shading tools and is an invaluable part of creating high quality surfaces.
The addon creates cross-section on selected objects.
Open the Edit-> Preferences ->Add-ons
Click on install button and point to the downloaded zip file.
The add-on is instaled under ObjectMenu > Create sections
Export IGES Addon for Blender creates subdivision limit surfaces and saves it as IGES file.
From Blender using the default options.