altitude option in featureToPolygon #Feature2Mesh

[Oncledjoe]

Hello,
This issue is about the projection of a polygon, which came from a wfs stream, with no Z, on the elevation layer. As we can see in example/globe_wfs_extruded.html it works for LineString( function altitudeLine(properties, contour)).
The idea is to implement a similar function for polygon. But in Feature2Mesh if we follow the same process than linestring it doesn't work.
It is the fault of getProperty called in featureToPolygon, it always returns 0 (it is because it tries to execute the function: property(...args) equivalent to options.altitude(geometry.properties) when i need options.altitude(feature.vertices)).
Furthermore getProperty is not used in featureToLine for the same operation, hence its success.
In resume: Can you fix featureToPolygon to make it look like at featureToLine with sames functionality.
I hope to be clear. Thanks a lot.
Best Regards,
Oncledjoe

[gchoqueux]

It's a regularly requested feature. It would be great to clamp object to terrain with feature2Mesh.

[Oncledjoe]

I agree, I develop a scientist web platform for cnrs and most of spatial data are polygon 2D. Without this feature, Itwons becomes less interesting. A quick modification of featureToPolygon give that:

It wills not work for very sharply terrain I thinks, but it's a beginning.

[gchoqueux]

if you won't project 2D polygons from WFS on the terrain you could use ColorLayer, see this example