Best way to get all Face's in model?

soldatino

I had the same problem, but I need to get the "material" of each face.
So I had a lot of problems because the "material" is hereditary if there is (or not) in the groups of faces (or nested groups). So it is really difficult to get the tree of the materials of all the faces.
So I wrote this inelegant recursive sub, and it works fine for me.

def pov_ex()
   model=Sketchup.active_model 
   entities=model.entities
   entities.each do |entity|
        if entity.typename=="ComponentInstance"
            entity.explode
            pov_ex()
        elsif entity.typename=="Group"
            entity.explode
            pov_ex()
        end
   end
end

at the end, after material's extraction, I wrote a "model.abort_operation" so all the entities return to original state and are not corrupted by explode.
But a question... this code works really slow, I'd like to find a better way....

thomthom

@soldatino said:

But a question... this code works really slow, I'd like to find a better way....

There are two reasons your code is slow:

You're comparing strings a lot. Don't use .typename to check for entity type. It's very slow. ( See more performance tips here: http://forums.sketchucation.com/viewtopic.php?f=180&t=25305#p217180 )
Instead, test for its class: e.is_a?( Sketchup::Group )
Exploding is very slow in SU. ( and if your script should fail at some point and halt - you're left with a broken model. )

I have a plugin that transfer the group/component materials onto the faces with default materials - here's an extract from that plugin:

<span class="syntaxdefault"><br />  def self</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">instance_materials_to_faces<br />    model </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> Sketchup</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">active_model<br />    model</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">start_operation</span><span class="syntaxkeyword">(</span><span class="syntaxstring">'Instance Material to Faces'</span><span class="syntaxkeyword">,</span><span class="syntaxdefault"> true</span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">    self</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">instance_material_to_faces</span><span class="syntaxkeyword">(</span><span class="syntaxdefault"> model</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">selection</span><span class="syntaxkeyword">,</span><span class="syntaxdefault"> nil </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">    model</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">commit_operation<br />  end<br />  <br />  def self</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">instance_material_to_faces</span><span class="syntaxkeyword">(</span><span class="syntaxdefault"> entities</span><span class="syntaxkeyword">,</span><span class="syntaxdefault"> material </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">    for e in entities<br />      if TT</span><span class="syntaxkeyword">;;</span><span class="syntaxdefault">Instance</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">is</span><span class="syntaxkeyword">?(</span><span class="syntaxdefault"> e </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">        temp_material </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> </span><span class="syntaxkeyword">(</span><span class="syntaxdefault">e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">material</span><span class="syntaxkeyword">)</span><span class="syntaxdefault"> </span><span class="syntaxkeyword">?</span><span class="syntaxdefault"> e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">material </span><span class="syntaxkeyword">;</span><span class="syntaxdefault"> material<br />        d </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> TT</span><span class="syntaxkeyword">;;</span><span class="syntaxdefault">Instance</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">definition</span><span class="syntaxkeyword">(</span><span class="syntaxdefault"> e </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">        self</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">instance_material_to_faces</span><span class="syntaxkeyword">(</span><span class="syntaxdefault"> d</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">entities</span><span class="syntaxkeyword">,</span><span class="syntaxdefault"> temp_material </span><span class="syntaxkeyword">)</span><span class="syntaxdefault"> </span><span class="syntaxcomment"># Recursive call<br /></span><span class="syntaxdefault">        e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">material </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> nil<br />      elsif e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">is_a</span><span class="syntaxkeyword">?(</span><span class="syntaxdefault"> Sketchup</span><span class="syntaxkeyword">;;</span><span class="syntaxdefault">Face </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">        e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">material </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> material if e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">material</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">nil</span><span class="syntaxkeyword">?<br /></span><span class="syntaxdefault">        e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">back_material </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> material if e</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">back_material</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">nil</span><span class="syntaxkeyword">?<br /></span><span class="syntaxdefault">      end<br />    end<br />  end<br /></span>

Note that I have to custom methods here, not explained:
TT::Instance.is?( e ) returns true if the entity is a Group or ComponentInstance
TT::Instance.definition( e ) return the definition of a Group or ComponentInstance

soldatino

Thanks for your responce!
Yes, teorically the strings compare is ever slow ... but here the difference is irrelevant more than in other languages, I checked a large file, and the part of the scanning and explode sub is the 99.99% of the working code of my parser.

if entity.is_a?(Sketchup::ComponentInstance)
and groups ...
start 13:49:42 -> end 14:08:26

if entity.typename=="ComponentInstance"
and groups ..
start 14:11:30 -> end 14:29:07

In the second reason (explode is slow insted of get from material list) you are right 100%, but it is a bit complicated for me at this time (I am new about skup database).... but next time I must to improve at...
I was hoping that there are something like these easy :
group_parent.face .... group_parent.group ...
but the only parent seems to be the entire list of materials...
Thanks again, I apologize for my bad english.

thomthom

@soldatino said:

Yes, teorically the strings compare is ever slow ... but here the difference is irrelevant more than in other languages, I checked a large file, and the part of the scanning and explode sub is the 99.99% of the working code of my parser.

It's a significant difference - check out the test data in this thread: http://forums.sketchucation.com/viewtopic.php?f=323&t=19576&st=0&sk=t&sd=a&start=15#p166698

@unknownuser said:

is_a? - 16.297c
kind_of? - 16.141c
class - 18.703c
typename - 88.703c

soldatino

@thomthom said:

............
2. Exploding is very slow in SU. ( and if your script should fail at some point and halt - you're left with a broken model. )

ok! I changed my way and it seems work alot faster! (for my plugin converter 2 POV-Ray script).
note: At this time I get only the color of the parent object(s) and not texture...

 def pov_find_faces(entities,tform,layername)
  entities.each do |entity|
    if entity.is_a?(Sketchup;;Face)
      pov_write_face(entity, tform)
    elsif entity.is_a?(Sketchup;;Group)
      if entity.material
        if entity.material.color
          $levelcolor[$level]=entity.material.color
        else
          $levelcolor[$level]=$levelcolor[$level-1]
        end
        if entity.material.alpha
          $levelalpha[$level]=entity.material.alpha.to_s
        else
          $levelalpha[$level]=$levelalpha[$level-1]
        end
      else
        $levelcolor[$level]=$levelcolor[$level-1]
        $levelalpha[$level]=$levelalpha[$level-1]
      end
      $level+=1
      pov_find_faces(entity.entities,tform * entity.transformation,entity.name)
    elsif entity.is_a?(Sketchup;;ComponentInstance)
      if entity.material
        if entity.material.color
          $levelcolor[$level]=entity.material.color
        else
          $levelcolor[$level]=$levelcolor[$level-1]
        end
        if entity.material.alpha
          $levelalpha[$level]=entity.material.alpha.to_s
        else
          $levelalpha[$level]=$levelalpha[$level-1]
        end
      else
        $levelcolor[$level]=$levelcolor[$level-1]
        $levelalpha[$level]=$levelalpha[$level-1]
      end
      $level+=1
      pov_find_faces(entity.definition.entities,tform * entity.transformation,entity.name)
    end  
  end
  $level=$level-1
  #UI.messagebox($level.to_s)
end