Galileo 3d model conversion

README.md

@@ -63,6 +63,11 @@ In Celestia name "Galileo" is used for the *other* spacecraft, not
 for the EU GNSS. So the name used in development here adds `-gnss`,
 ala, `galileo-gnss.ssc`, whereas the other GNSS don't.
 
+## Galileo
+Galileo 3D models are from the ESA:
+
+* https://gssc.esa.int/education/galileo3d/
+
 
 ## TLE Sources
 
@@ -96,11 +101,36 @@ Orbital and astronomy computations in python.
 * https://pyorbital.readthedocs.io/
 
 
-## 3D Models
+# 3D Models
+Celestia uses an old 3D proprietary format from an old 3D application in
+`.3ds` format. It also has it's own format `.cmod`.
 
-Galileo 3D models are from the ESA:
+## 3D Model Conversion
+Recent versions of Blender don't export `.3ds` format. But old versions
+of Blender, such as 2.79b do work. Get an old version here:
 
-* https://gssc.esa.int/education/galileo3d/
+* https://download.blender.org/release/Blender2.79/
+
+Launch `blender`, import, export.
+
+```
+# Go to https://gssc.esa.int/education/galileo3d/
+# and download the Galileo_3D.zip file.
+# It generates a unique URL, afaict.
+unzip Galileo_3D.zip
+
+# Get old Blender
+wget https://download.blender.org/release/Blender2.79/blender-2.79b-linux-glibc219-x86_64.tar.bz2
+tar xf blender-2.79b-linux-glibc219-x86_64.tar.bz2
+cd blender-2.79b-linux-glibc219-x86_64
+./blender
+```
+
+Blender creates a new file on launch.
+Go to `File --> Import --> Wavefront (.obj)`.
+Import the file, such as `galileo.obj`.
+Go to `File --> Export --> 3D Studio (.3ds)`.
+Save the file, such as `galileo-gnss.3ds`.
 
 
 # License / Copyright