Skip to main content
Solved

How to remove elevation from BIM file?


oscard
Influencer
Forum|alt.badge.img+21

Good morning.

 

I'm putting together a workspace to transform a Revit file into Cesium 3D tiles. Overall, it is a pretty straightforward process, but I'm facing an issue with the elevation.

 

The building stored in the Cesium 3D tiles is floating, so I need to offset the Z to put it in floor level over a 2D basemap. I've been using the Offsetter transformer with lots of trial and errors until getting it right, but I would like to know if there is a better way.

 

So the question is: Is it possible with FME to make that "elevation removal" automatic?

Best answer by chrisatsafe

Hi @oscard​ ,

If you have floating features you can use an ElevationExtractor (1 in the image)or BoundsExtractor (2 in the image) to get the z value, then set the Offset Z value to negative @Value(_elevation) or @Value(_zmin). This extract the elevation to an attribute (either _elevation or _zmin depending on the transformer you use) which can then be used to offset in the Offsetter. 2021-02-02_14-13-54

View original
Did this help you find an answer to your question?

2 replies

chrisatsafe
Contributor
Forum|alt.badge.img+2
  • Contributor
  • Best Answer
  • February 2, 2021

Hi @oscard​ ,

If you have floating features you can use an ElevationExtractor (1 in the image)or BoundsExtractor (2 in the image) to get the z value, then set the Offset Z value to negative @Value(_elevation) or @Value(_zmin). This extract the elevation to an attribute (either _elevation or _zmin depending on the transformer you use) which can then be used to offset in the Offsetter. 2021-02-02_14-13-54


oscard
Influencer
Forum|alt.badge.img+21
  • Author
  • Influencer
  • February 3, 2021
chrisatsafe wrote:

Hi @oscard​ ,

If you have floating features you can use an ElevationExtractor (1 in the image)or BoundsExtractor (2 in the image) to get the z value, then set the Offset Z value to negative @Value(_elevation) or @Value(_zmin). This extract the elevation to an attribute (either _elevation or _zmin depending on the transformer you use) which can then be used to offset in the Offsetter. 2021-02-02_14-13-54

Hi! Thanks for the answer!

That worked.

 

I have to aggregate the geometries first and then apply the ElevationExtractor, otherwise all the buildings floors are pushed to the ground.


Cookie policy

We use cookies to enhance and personalize your experience. If you accept you agree to our full cookie policy. Learn more about our cookies.

 
Cookie settings