Geolocation
ℹ️ Work in progress
This wiki page explains how to setup the geolocation of your FDS case, place Objects at specific coordinates, and import terrains from qgis2fds.
FDS MISC namelist has specific parameters to set the geographic location of the domain origin:
-
ORIGIN_LONandORIGIN_LATset the geographic coordinates (longitude and latitude) in decimal degrees, in a WGS84 (World Geodetic System 1984) 2D coordinate reference system (CRS); -
NORTH BEARINGspecifies the North bearing in decimal degrees of the y-axis of the FDS absolute reference system for the domain.
FDS does not use those numbers, these are only useful when interfacing with pre or post-processing tools as qgis2fds and BlenderFDS.
You can easily find the geographic coordinates of the point where you are now with any GPS device, as your mobile phone.
For more info on WGS84 see Wikipedia
In BlenderFDS you can easily enter those coordinates within the MISC namelist panel.
The panel allows you to also enter a toponym for reference.
If you click on the world icon, the exact location you choose is opened and pinned
on an OpenStreetMap world map.
At the bottom of the panel the exact UTM WGS84 coordinates of the point are calculated and shown.
For more info on UTM see Wikipedia
After correctly georeferencing the FDS domain origin, you can start putting FDS entities at specific geographic positions.
The Geolocation sidebar panel allows you to position the Blender 3DCursor or any Object origin at specific coordinates.
These coordinates shall be always expressed in decimal degrees according to a WGS84 CRS. At the bottom of the panel, there is a button opening a website where you can transform your type of coordinates to the required format.
If you want to do more than just putting Object instances on the right spot on Earth,
you probably need to take a look at the qgis2fds plugin
for QGIS, an open source and free geographical information system.