Menu: Utilities->Swap normals
This command can be applied to lines or surfaces (in geometry mode) or to elements (in mesh mode). A selection is made (see Entity selection) and the orientation of the selected entities is inverted.
Viewing commands (zoom, rotation, etc.) can be applied and the normals will remain on the screen.
When this command is applied to surfaces or mesh elements, you can choose one of the following options:
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Note: With the Color option set (available in the Contextual mouse menu), all surfaces or elements are drawn in filled color. Their front side will be drawn in their regular color, and their back face in yellow.
Note: Volumes are correctly oriented by GiD, regardless of their surface orientation.