When you flatten shapes with a high degree of curvature, the result might be distorted. To get a more accurate result, create split lines to use as control curves.
Control curves help shape the flattened surface. Primary edges are control curves that do not change in length or shape when flattened.
In this example, the swept surface feature is flattened without using control curves:
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| Folded surface |
Flattened surface (without control curves) |
Next, split lines are added and used as primary edges to divide the folded surface into areas with less curvature:
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| Folded surface |
Flattened surface (with control curves) |