Basically, you are asking to switch the geometric kernel from surface to solids, which can only be done if you build from scratch.
That won’t happen, I guess, as SketchUp is merely an AEC-modeller were most shapes are pretty straight forward.
That said, it is still possible to create solids (with or without extensions) with more complex shapes by subtraction, trimming or deformation. They can become accurate when you have more segments, but they will still be just edges and faces, and will have inaccuracies.
(ie. a circle can have a centerpoint and calculated circumference, but as soon as you edit it (merge with other geometry) that info will be lost and you get approximate area’s or total length of the segments instead of a calculated perimeter)
A SketchUp solid is not the same as Nurbs-solid.
That said, the watertight objects in SketchUp can have all sorts of attributes, one of them being able to recognize if it is a solid, so why not have ‘Substance or Resource’ being one of them.
(I specifically do not want to use ‘Material’ because it refers to the all ready existing, which is only a cosmetic thing in SketchUp)
Substance or Resource would be a new Class or Object in the API (not sure if I phrase correctly @DanRathbun) with attributes like the ones you use in the Periodic System.(Mass, E, Density, Stress, Coefficient of expansion) or heritage (Pine from scandinavie, steel from recycled bins)
In SketchUp, we would use the Mass, primarily and heritage. Extensions could work out the others like expansion (eg. You set the geolocation, the date in Shadows and it picks the right temperature, so you can see how much your rail would expand)
The ability to report would be by File->Generate Report, as it is now all ready (we can now only generate the dynamic component and Advanced Attributes)
With the upcoming awareness of the limited resources, SketchUp could become more import in the process.
Edit: pinging Sefaira team, they have localized data for temperature and are more into physics
@niraj.poudel @corney