Click or drag to resize

EarthAnchorPointGetModelToEarthTransform Method

Gets a transformation from model coordinates to earth coordinates. This transformation assumes the model is small enough that the curvature of the earth can be ignored.

Namespace:  Rhino.DocObjects
Assembly:  RhinoCommon (in RhinoCommon.dll)
Since: 5.0
public Transform GetModelToEarthTransform(
	UnitSystem modelUnitSystem


Type: RhinoUnitSystem
The model unit system.

Return Value

Type: Transform
Transform on success. Invalid Transform on error.
If M is a point in model coordinates and E = model_to_earth*M, then E.x = latitude in decimal degrees E.y = longitude in decimal degrees E.z = elevation in meters above mean sea level Because the earth is not flat, there is a small amount of error when using a linear transformation to calculate oblate spherical coordinates. This error is small. If the distance from P to M is d meters, then the approximation error is latitude error <= longitude error <= elevation error <= 6379000*((1 + (d/6356000)^2)-1) meters In particular, if every point in the model is within 1000 meters of the m_model_basepoint, then the maximum approximation errors are latitude error <= longitude error <= elevation error <= 8 centimeters.
See Also