A base class representing a datum surface (level, grid or reference plane) in Autodesk Revit.

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Namespace:
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Autodesk.Revit.DB

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Assembly:
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RevitAPI
(in RevitAPI.dll) Version: 21.0.0.0 (21.1.1.109)

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Since:
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2016

# Syntax

# Remarks

A DatumPlane represents a 3d surface with finite extents. It can be either a rectangle with arbitrary orientation, or a cylinder
whose axis is parallel to the project z-axis.
If a datum is visible in a plan or section view, it will be displayed as one or more curves. These curves are determined by the
intersection of the datum surface with the cut plane of the view. By default, the extents of these curves reflect the 3d extents
of the datum surface. If the surface is a plane, then the extents represent the projection of the surface onto the cut plane. This
matters, for example, when viewing a datum plane, really a 3d rectangle, along one of its diagonals. The extents of the curve
do not vary with the location of the view, because we use the projection of the rectangle and not the actual intersection. If the
surface is a cylinder, then the extents reflect the actual intersection of the surface with the cut plane.
In addition, the curves that represent a DatumPlane can be modified on a view specific basis. In this case, the ends of the curve no
longer reflect the 3d extents of the datum.

# Inheritance Hierarchy

System
Object

Autodesk.Revit.DB Element

Autodesk.Revit.DB DatumPlane

Autodesk.Revit.DB Grid

Autodesk.Revit.DB Level

Autodesk.Revit.DB ReferencePlane

Autodesk.Revit.DB Element

Autodesk.Revit.DB DatumPlane

Autodesk.Revit.DB Grid

Autodesk.Revit.DB Level

Autodesk.Revit.DB ReferencePlane