# 14.2.1 AbstractLocal3dCrs

 Topic Version 1 Published 09/11/2015 Topic Change History For Standard RESQML v2.0.1 Stereotypes: XSDcomplexType,XSDtopLevelElement

Defines a local 2D+1D coordinate reference system (CRS), by translation and rotation, whose origin is located at the (X,Y,Z) offset from the projected and vertical 2D+1D CRS.

The units of measure in XY follow the projected CRS. The units of measure of the third coordinate is determined in the depth or concrete type.

ArealRotation is a plane angle.

Defines a local 3D CRS, which is subject to the following restrictions:

• The projected 2D CRS must have orthogonal axes.
• The vertical 1D CRS must be chosen so that it is orthogonal to the plane defined by the projected 2D CRS.

As a consequence of the definition:

• The local CRS forms a Cartesian system of axes.
• The local areal axes are in the plane of the projected system.
• The local areal axes are orthogonal to each other.

This 3D system is semantically equivalent to a compound CRS composed of a local 2D areal system and a local 1D vertical system.

The labels associated with the axes on this local system are X, Y, Z or X, Y, T.

The relative orientation of the local Y axis with respect to the local X axis is identical to that of the global axes.

Table 14.2.1-1 Attributes

Name

Data Type

Notes

ArealRotation

PlaneAngleMeasure

The rotation of the local Y axis relative to the projected Y axis.

• A positive value indicates a clockwise rotation from the projected Y axis.
• A negative value indicates a counter-clockwise rotation form the projected Y axis.

ProjectedAxisOrder

AxisOrder2d

Defines the coordinate system axis order of the global projected CRS when the projected CRS is an unknown CRS, else it must correspond to the axis order of the projected CRS.

ProjectedUom

LengthUom

Unit of measure of the associated projected CRS. When the projected CRS is known, it must be the same as the unit defined by the projected CRS.

VerticalUom

LengthUom

Unit of measure of the associated Vertical CRS. When the vertical CRS is known, it must be the same as the unit defined by the vertical CRS.

XOffset

double

The X location of the origin of the local areal axes relative to the projected CRS origin.

BUSINESS RULE: The value MUST represent the first axis of the coordinate system.

The unit of measure is defined by the unit of measure for the projected 2D CRS.

YOffset

double

The Y offset of the origin of the local areal axes relative to the projected CRS origin.

BUSINESS RULE: The value MUST represent the second axis of the coordinate system.

The unit of measure is defined by the unit of measure for the projected 2D CRS.

ZIncreasingDownward

boolean

Indicates that Z values correspond to depth values and are increasing downward, as opposite to elevation values increasing upward. When the vertical CRS is known, it must correspond to the axis orientation of the vertical CRS.

ZOffset

double

The Z offset of the origin of the local vertical axis relative to the vertical CRS origin. According to CRS type (depth or time) it corresponds to the depth or time datum.

BUSINESS RULE: The value MUST represent the third axis of the coordinate system.

The unit of measure is defined by the unit of measure for the vertical CRS.

Derived From: AbstractResqmlDataObject

Derived Classes: LocalDepth3dCrs, LocalTime3dCrs

Table 14.2.1-2 Relationships

Role

Class

Cardinality

VerticalCrs

AbstractVerticalCrs

1..1

ProjectedCrs

AbstractProjectedCrs

1..1