Compiling Dataset - in tweed.xml, what is toOrigin and fromOrigin?

[leekkww]

Compiling Dataset - in tweed.xml, what is toOrigin and fromOrigin?

[twak]

The GML should show up - but the system does have to guess how to position it in space (it searches for a hard-coded String in the GML file). Perhaps there's a bug. Can you send the GML file?

The tweed.xml is a serialized version of the org.twak.tweed.TweedSettings class. toOrigin is the inverse of fromOrigin, and contains a transform to move the GML data to the origin in a DefaultGeocentricCRS.CARTESIAN coordinate system. Details here.

<genList> is the list of layers (gml, minimesh etc...). The GML one of these GISGen.

It is generally best to try and build a tweed.xml by adding layers using the + button in the user interface.

[leekkww]

Woah! I didn't realize that you can add a GML layer with the + button. I've just been adding it with File->New->selecting the GML file, and that doesn't make the GML file show up. The GML file is loaded now that I used +, thank you!

I see that the system guesses the position of the GML in space using info in the GML file. Just wondering, how does that work with obj meshes that you import? Are the obj meshes imported in arbitrary locations?

Also, how does the system link the GML data with minimesh? Is there a mapping from GML polygon -> all related meshes somewhere in the Glasgow dataset?

[twak]

Obj meshes are imported in their "native" coordinate systems. Usually (unlike GML CRSes) these are near the origin.

There is no direct link between the GML data and the minimesh because the mesh is typically in an arbitrary CRS. You have to align the mesh using the align tool:

• select the minimesh in the list of layers (Gens)
• select the align tool
• right-click in the 3d view 4 times: twice on the map/GML data and twice on the mesh. The tool will align these two points
• remember to save alignment (this writes out the new coordinate system to the minimesh's index.xml file. This ensures the transform exists after you re-load the project