How to transformate geodetic coordinate into Revit local coordinate?

[moonlikestoneBX57A]

Hi, in my case, in the first according to the survay data I set the base point in Revit project, and in the second place some curved beams will be created.

The problem is the coordinate system of those geometry data(curve of those curve beams) are geodetic coordinate, and I don't know how to transformate it into Revit local coordinate system.

Is there has any equation about this issue?

Maybe I can use UnitUtils to slove the problem? But how to do it? I didn't find any example....

[jeremy_tammik]

I don't know exactly how your "geodetic" coordinates are defined and how your Revit model site information has been set up, so a precise answer is not possible.

In any case, however, the UnitUtils are not of much use here; they just support translation between the internal database units used within the Revit project database and the display units that the end user sees on the screen in the user interface:

https://www.revitapidocs.com/2023/09fb3758-fff0-42f1-baf7-35043f66b2ce.htm

Afaik, the main tool for correlating the Revit coordinate system with the real world is the site location:

https://knowledge.autodesk.com/support/revit/learn-explore/caas/CloudHelp/cloudhelp/2023/ENU/Revit-M...

How the site is set up defines how real-world geographic points translate into the Revit model:

https://duckduckgo.com/?q=transform+geodetic+into+Revit+local+coordinates

[RPTHOMAS108]

It is odd to have local model geometry in that system I don't think inherent Revit functionality will help much here since that is likely mainly focused on locating a single datum point (origin of LTP) for the project on the surface of the earth in that system (i.e. no elevation from ground level component).

The best source of information I could find for it is probably here:

Geographic coordinate conversion - Wikipedia

Specifically the sections:

From geodetic to ECEF coordinates
Geodetic to/from ENU coordinates
        From ECEF to ENU

Note the following also:

"phi is the geodetic latitude; the geocentric latitude is inappropriate for representing vertical direction for the local tangent plane and must be converted if necessary."

ECEF: Earth centred earth fixed (vector from centre of earth to point on earth surface)

LTP ENU: Local tangent plane (east, north up), this is likely your end goal I think.

When you have a solution it would be good if you can share.