Revit 2025 API
Curve |
Determines if this CurveLoop is oriented counter-clockwise (CCW) or clockwise (CW) with
respect to the specified 3D direction.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.0.0.0 (25.0.0.0)
Syntax
public bool IsCounterclockwise( XYZ normal )
Public Function IsCounterclockwise ( normal As XYZ ) As Boolean
public: bool IsCounterclockwise( XYZ^ normal )
member IsCounterclockwise : normal : XYZ -> bool
Parameters
- normal XYZ
- The normal vector to the plane used for this determination.
Return Value
BooleanTrue if the curve loop is oriented counter-clockwise with respect to the specified 3D direction, false if the loop is oriented clockwise.
Exceptions| Exception | Condition |
|---|---|
| ArgumentNullException | A non-optional argument was null |
| InvalidOperationException | The curve loop is open or consists of a single unbound curve; counterclockwise determination has no meaning. |
Remarks
CCW means that the projection of the CurveLoop onto a plane having "normal" as its oriented normal is CCW.
This method should only be called if the loop is closed and has a non-singular projection onto the plane
(i.e., the projection should have no self-intersections and should not be degenerate or even
nearly degenerate). The return value in other cases is indeterminate.
See Also