To Create a Domain
1. Click Restyle > Curve > On Facet.
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You can also use curves created from sharp edges, from border, intersection curves, or any of the analysis curves for creating domains. A domain can also be created in a region bounded by multiple curves.
2. Select points on the facets such that the resulting curve forms a closed loop.
3. Click Create Domain and click anywhere inside the closed loop. Restyle creates a domain and highlights it.