Hi Michael,

OBJ files never have a spatial reference, unless there is an auxiliary file (e.g. a .wld or .prj file for example). Your file also doesn't seem to have a coordinate system and the coordinates of the OBJ geometry are far outside the valid range for EPSG:5514. So what you should do, is offset your OBJ to the right location (e.g. using an Offsetter transformer) if you know the point of origin, provided the OBJ's unit is metric and that it's not rotated. Use a CoordinateSystemSetter and set it to EPSG:5514. Then, write it to Cesium 3D Tiles (and set the Output Coordinate System on the writer to EPSG:4326). FME will take care of the reprojection. Not sure though how it deals with the z scale. If your OBJ seems way too high, use a CsmapReprojector instead and set the Vertical Handling to "Heights are relative to the ellipsoid(s) or geocentric".

Hope this will produce usable tiles! Can't test myself unfortunately (en route without laptop).

Hi again @michaelknave,

I took a look at the Cesium 3D tile writer and it seems to me that it simply doesn't chop up single features. There's nothing you can set, except the maximum amount of features per tile.

I already deleted the file (and I can no longer download it), but your OBJ only consists of 1 3D mesh, right? So that's just 1 feature. The writer is designed for situations where you have a large amount of features, e.g. 1 million 3D buildings within a city. With a (default) of 300 features per tile, that should produce around 3300 tiles.

The only thing you could do, is chop the building into multiple parts yourself. However, creating 3D tiled meshes in FME is a royal pain. I have created a PythonCaller script once though that can do it, but it's quite slow and it doesn't create straight tile edges but jagged edges instead, as it merely checks if a triangle/face is inside a tile or not...

Sander