Retrieving parent definition

Frankn

I can go through the definition list and get an array of all the components but I'd like to get an array of only the parent components. How can the parent definition of a component with subcomponents be retrieved from the definition list if the definition doesn't have an instance?

Sorry if this has been asked before but I can't seem to find anything searching the forum.

Thanks,
Frank

Chris Fullmer

Thats a little trickier than it might sound. Just because a component is inside another component, that doesn't mean that is the only place it exists.

But I think you could still figure out what you're looking for by iterating through all the definitions, and then iterate over all instances and check what their parent is. It would be possible that some instances will be directly in the modelspace while others will be nested. Its up to you to determine how you want to treat the ones that have mixed parents.

Something like that should work, depending on what you're thinking to do with the components you find.

Chris Fullmer

Or maybe this is an instance where simply finding all component instances inside the model space is a good way to go. Use the cool grep feature:

outer_instances = Sketchup.active_model.active_entities.grep(Sketchup;;ComponentInstance))

Dan Rathbun

You would test the definitions' entities collections to see if it contains any instances.

dl = Sketchup.active_model.definitions() pars = dl.reject {|d| d.entities.grep(Sketchup::ComponentInstance).empty? }

TIG

model=Sketchup.active_model
definitions_containing_instances = []
model.definitions.each{|d|
  next if d.group? || d.image? ### for compos only
  d.entities.each{|e|
    if e.is_a?(Sketchup;;ComponentInstance)
      definitions_containing_instances << d
      break
    end
  }
}

This code makes an array named ' definitions_containing_instances', which contains only component-definitions that contain another component-instance.
Groups and Images are ignored.
It will always contain any component-definition that matches this simple rule... so an instance of defn A inside defn B adds def B to the list, AND and instance of defn C inside defn A also adds defn A to the list...
It you only want one level of nested to return positive, then you you can check for the defn having an instance with a parent that is not the model and the skip it...

model=Sketchup.active_model
definitions_containing_instances = []
model.definitions.each{|d|
  next if d.group? || d.image? ### for compos only
  nested=false
  d.instances.each{|i|
    if i.parent != model
      nested=true
      break
    end
  }
  next if nested
  d.entities.each{|e|
    if e.is_a?(Sketchup;;ComponentInstance)
      definitions_containing_instances << d
      break
    end
  }
}

Frankn

Thanks for taking the time to reply,

@Chris, I've never heard of grep before, which isn't all that surprising since I'm still very much a newbie to all this. I'll have to look into it and see how helpful it can be in certain instances. I tried to run your code but it only returns instances... I'm thinking there's something you might of left out which is cool it'll give me something to play with and see if I can figure it out on my own which is how I seem to learn the best.

@Dan, thanks for the simple solution which works great! Again, you're using grep which I have no clue of what it does but this line of code I'm sure will be helpful in understanding it.

@Tig, Thanks for the more detailed code, it works just as desribed and does exactly what I need it to do. I'll study the code later on to try and fully understand what's going on there. One question regarding your code, any reason or advantage to using << instead of .push()?

It's always interesting to see that there are many ways to accomplish the same task. Thanks for your time guys.

One suggestion if I may do so, maybe this should be added to the code snippets thread? Asking is always my last resort so I'm getting pretty good at searching for answers and I couldn't for the life of me find anything pertaining to this.

Frank

TIG

<< IS .push() !
Ruby has many dialects...

Dan Rathbun

@frankn said:

@Chris, I've never heard of grep before, ...
@Dan, ... Again, you're using grep which I have no clue of what it does ...

The docs for SketchUp API classes do not list standard Ruby methods that are inherited. (This is normal also in the Standard Ruby docs, however the latter lists what libraries are "mixed" in. The SketchUp docs do not. [I know I have requested this be changed.])

To list the ancestors of a class, use the ancestors() method:
Sketchup::Entities.ancestors %(#008000)[>> [Sketchup::Entities, Enumerable, Object, Kernel]]

Checking on Enumerable shows that it is actually a library "mixin" module, that is mixed into collection type objects, to give them extended common functionality.

Consult the Standard Ruby Documentation to read the reference on the Enumerable library. (It is online, and I also posted the downloadable CHM (compiled HTML Help Markup,) in the Ruby Resources thread. (Follow the link in signature line.)

[Code] Grepping entities

Dan Rathbun

@tig said:

<< IS .push() !
Ruby has many dialects...

The correct term would be aliases, ...

... however this example is not a case of a simple method alias.
In fact looking at the C code.. both methods call the C-side function %(#0080BF)[rb_ary_push] with different arguments.

Synopsis:

BOTH Ruby methods return the receiver array, so call chaining can be used.

<<() takes ONE argument.

push() can take a multiple argument list.

a = []

a << 1,2,3 %(#008000)[Error: #<SyntaxError: (eval): compile error (eval): syntax error, unexpected ',', expecting $end a << 1,2,3 _______^>]

a <<( 1,2,3 ) %(#008000)[Error: #<SyntaxError: (eval): compile error (eval): syntax error, unexpected ',', expecting $end a <<( 1,2,3 ) ________^>]

a.<<( 1,2,3 ) %(#008000)[Error: #<ArgumentError: (eval):0:in<<': wrong number of arguments (3 for 1)>
(eval)
(eval):0]`

a.push( 1,2,3 ) %(#008000)[[1, 2, 3]]

Dan Rathbun

@frankn said:

One suggestion if I may do so, maybe this should be added to the code snippets thread?

I added a link to TIG's post, to the "Code Snippets" Subject Index, under the title:

"Collecting definitions that ARE parents of component instances"

My one-liner is not worthy, it will slow down as the model gets bigger (and does not ignore images & groups.)

Chris Fullmer

Frankn, just to clarify for myself, but you really want only components that have sub-components in them? or is it that you want a list of definitions whose instances are NOT sub-components?

danielbowring

The parent of every ComponentInstance
Sketchup.active_model.definitions.map() {|e| e.instances }.flatten.map() {|e| e.parent}.uniq

Every ComponentDefinition that has sub-components
Sketchup.active_model.definitions.find_all() {|e| e.entities.find() {|e| e.class == Sketchup::ComponentInstance } }

Every ComponentInstance that has sub-components
Sketchup.active_model.definitions.find_all() {|e| e.entities.find() {|e| e.class == Sketchup::ComponentInstance } }.map() {|e| e.instances }.flatten

To get the parent of a Entity, use entity.parent.

Frankn

@chris fullmer said:

Frankn, just to clarify for myself, but you really want only components that have sub-components in them? or is it that you want a list of definitions whose instances are NOT sub-components?

Hey Chris, I wanted to be able to find the parent definition of components with subcomponets that aren't in the model but still in the definition list. Hope that makes sense... but if it doesn't, basically the 2nd code that Tig shared is what I wanted to accomplish.