Why IGES often needs tessellation
IGES can describe trimmed surfaces, NURBS curves, wireframes and other precise geometric entities. A real-time 3D renderer needs those entities converted into triangles before it can draw them.
That conversion is called tessellation. Its result depends on tolerances and topology, so it is better performed by a compatible CAD engine or by the system that created the model than guessed by a basic file viewer.
Choose a practical fallback
Ask for STL when you need a straightforward triangle mesh for visual review. Ask for indexed OBJ when object or group divisions matter. Keep the original IGES file alongside the review copy so engineering data is not lost.
If exact surfaces, tolerances or manufacturing features must be checked, use the source CAD application or a validated engineering workflow instead of relying on a tessellated preview.
Keep sensitive geometry local
Uploading an IGES model to a browser converter can disclose customer geometry or unreleased product details. CadRoam performs its supported inspection locally and does not upload model contents to Eutopix Labs.
A sender should still remove confidential or irrelevant components before distributing any derivative mesh to another person.