1
$\begingroup$

I downloaded a 3D truck and a semi-trailer from a 3D Graphic web site and loaded it into Blender. After separating the wheels into a separate Blender file as well as the truck body, I then exported these files as glb to use in Godot. They loaded into Godot perfectly. My aim is to do a physics animation.

The issue is that the new truck is many times bigger than a Godot vehicle.node tutorial I had used for a car that came with the tutorial. The Godot wheel node radius was 0.5, but my imported truck wheels are 1.952m.

One thing I am concerned about is that if I shrink the truck I might have problems. When I did a Blender tutorial of a steel ball swinging on a chain to knock down a pile of blocks the tutor pointed out that the chain links and the ball were a several meters in size according to Blender measurements. He said he had to make them that size because Blender couldn't handle the processes at real sizes. The graphics would get all tangled up if he tried.

So how would you handle this? I need room for some parts of the semi-trailer that is attached to the truck. The functioning of these parts is important. Could Godot handle this? Should I shrink the truck and trailer in Blender or Godot? Reset the measurements in Godot?

$\endgroup$

1 Answer 1

1
$\begingroup$

In my experience, it is best to get the model as "right" as possible as early as possible. So I'd do all the scaling in Blender before exporting. To do so, it is best to set Blender scale units to "metric" units (if not already so) and then scale everything to real-world size.

The most important step is now to Apply settings apply all transformations. Then, your exported geometry should come into Godot the right size so your physics will be all correct.

As for your concern that blender physics could not handle real world sizes: This may be somewhat true if the real world objects are very large. If you want the truck to behave realistically, it should have its real size.

$\endgroup$
2
  • $\begingroup$ Thank you haarigertroll! What properties can we add in Blender that will successfully export to Godot and which format? What about weights? $\endgroup$
    – youkuya
    Commented Nov 26, 2020 at 3:30
  • $\begingroup$ AFAIK, physics data like weight is not transmitted in any exchange file format (best use GLTF) between Blender and Godot. So get your geometries right in Blender, import them in Godot and set your physics properties over there. $\endgroup$ Commented Nov 26, 2020 at 8:53

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .