Volume calculation from grouped solids

[DanRathbun]

@andlab

I have cases where it is organized geometry into groups, hence I know that is is possible to calculate the volumn from. The sketchup api allows volumn computation from component. So my thought was to at export from sketchup, copy these geometries to a compnent, calculate the voumn and then delete the component, hence obtaining the volumn but not exporting a component, which should not be a component.

That is the very difficult way of doing this. There is much simpler way.

a. In SketchUp, a group is a special type of component instance, so both have a component definition.
b. To access functions of the SUComponentInstance class, cast the group to a componentinstance.
c. Then call the SUComponentInstanceComputeVolume() function

See this topic thread …

Is there a function to know a group or a component is a solid group or a solid component?

In a roundabout way yes. Firstly, groups would need to be cast to a ComponentInstance using … SUGroupToComponentInstance Secondly you would attempt to get the volume of the instance using … SUComponentInstanceComputeVolume, and test the result for not SU_ERROR_NO_DATA (which is returned if the instance is not manifold.) Enhancement Issue logged:

… and this C API feature request …

C API has no direct boolean functions to test for manifold volumes · Issue #90 · SketchUp/api-issue-tracker · GitHub

@andlab

My question is: Is there any easy functions which allows copy of entities or faces directly to the component instance?

NO. Groups are an instance (a special subclass of component instance just as Image is.) Instances do not have entities collections, their definitions own the collection.