Blender scale (no, I don't have an infinitely small mesh, just a question about scale)

Development Asset Creation
1

Hi

I am working on a model of a real world location in my home town. Since I live in Denmark, I have access to the best open geographic data in the world :cool:

In this particular case I took a point cloud, trimmed it to fit my location of interest and triangulated it. The area is about 450 x 250 x 6 meters and so is the mesh in units in Blender (meters, not Blender units).

I export an fbx according to instructions I can find on the internet, and it looks ok. Scale set to 1.0

Whenever I imported it into UE4, I could open it in the static mesh editor just fine and zoom around the model, but as soon as I placed it in the world UE would crash.

After much fooling around I found that if I exported from Blender with scale 0.1 and then, after the import in UE, scale it to 10 (and thereby getting the same size as in Blender) it would work fine.

What is going on? Has anyone experienced the same with Blender? Or is it general for any 3D application?

2

You need to set the scene unit scale in Blender to 0.01 to get correct result. Then resize the mesh by 100 times and apply transforms. If you export a 450x250x6 meter mesh with unit scale 1 it will turn into a 45000x25000x600 meter mesh which is probably pretty bad.