Unique Groups

[medeek]

I am trying to figure out the behaviour of the "Unique" function. When I have a component that is composed of a number of groups and I make one of these component instances unique, then I edit the component and select one of the groups, it then will say something like: "Solid Group (11 in model)".

How do I make sure that the groups within a component are also unique?

[TIG]

Get a reference to each group, then check if it has multiple instances, if so make them unique...
For example...

groups.each{|group|
  d = group.entities.definition
  if d.instances[1] ### i.e. more than one instance
    d.instances[1..-1].each{|i| i.make_unique }
  end
}

[medeek]

I thought groups were always unique. Right clicking a component allows you to make it unique, however the same option does not appear for a group. The weird thing is if you select a group that has multiple instances and a component and then right click and select unique this will also make the group unique, strange.

[TIG]

Groups are just a special sort of component-instance.
A group's definition doesn't appear in the Component Browser.
Groups should be unique... but...
You can have multiple instances of a group.
To do it manually just copy a group several times...
Select one and Entity Info shows several instances.
But if you then edit a copied group, it becomes unique automatically - unlike a component.
So the make_unique method applied to a group [instance] is the same same as editing that group [which is not possible within the API otherwise].
Of course it also works with component-instances, just like the 'make_unique' tool within the context-menu.

Incidentally, definitions can either be usual 'vanilla' Components, or Groups [as outlined above], OR Images...
The definition.group? and definition.image? methods are there to help you determine the type of definition it is...

[slbaumgartner]

Groups are implemented as a special case of Components. They add some convenience methods that expose some aspects of the associated ComponentDefinition, and also a "lazy uniqueness" mechanism. By that I mean that when you copy a Group, it behaves just like a Component does - another instance is added to the ComponentDefinition. Only when you perform some action on that requires it to be unique does SketchUp clone a second ComponentDefinition and wire the Group to it (same thing as the make_unique method does). Any other copies remain associated with the original ComponentDefinition until you also alter them. For Group copies, it is a one-at-a-time thing.