Non-solid extrusions fail

[didimitrie]

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Expected Behaviour

Extrusions seem to be not really working with non-solid ones. A single/curve/polyline/polycurve line is extruded in an open surface, but threejs fills it up.

Affected Projects

Does this issue propagate to other dependencies or dependants? If so, list them here!

Reproduction Steps & System Config (win, osx, web, etc.)

StreamId: B1zNJbklm @ speckle hestia

[mswaidan]

Three.js extrusions are based on shapes. They're closed paths by definition (plus some holes), so I don't think an open threejs extrusion is possible. We'll need to treat open extrusions as breps in the converter.

[didimitrie]

hm... then we need to handle this via checking if the extrusion is closed or not (is this even in SpeckleCore?). If closed, we're cool, if not closed (ie, just a line of sorts), we'll need to write some custom code to extrude it. I guess.

I wouldn't treat them as breps, as this makes these things heavier than they need to be, unless what you had in mind is just try to extract a displayMesh like we do for breps though? and then in a threejs client we request just the displayMesh, and in a Rhino client we get the extrusion proper?