Offset top face only...need help!

[renderiza]

Hi, bellow is an attempt to offset the top face lines but I am running into some issues.

model = Sketchup.active_model
ents = model.active_entities
faces = ents.grep(Sketchup;;Face)
sel = model.selection

faces.each do |face|

  if face.normal.z == 1
    
    edges = face.edges
    edges.to_a.each do |e|

      p1 = e.start.position
      p2 = e.end.position
      
      x1 = p1.x
      x2 = p2.x
      y1 = p1.y
      y2 = p2.y
      
      length =  Math.sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)) 
      
      offset = 10.0
      
      x1p = x1 + offset * (y2-y1)/length #/
      x2p = x2 + offset * (y2-y1)/length #/
      y1p = y1 + offset * (x1-x2)/length #/
      y2p = y2 + offset * (x1-x2)/length #/
      
      newedges = ents.add_line([x1p,y1p,p1.z+5],[x2p,y2p,p2.z+5])
     
      sel.add newedges
    end

  end

end

Where do I start ...

Notice that when I add the line, the z coordinates have +5 added because if I make it same height as face the new edges break the next edge that it will offset and mess the result.

You can see what I mean if you replace "p1.z+5" to "p1.z" & "p2.z+5" to "p2.z". You need to have a face that where z axis = 1.

What I had in mind was to elevate the edges by 5 and somehow abstract the vertex position where the new edges intersect. Problem is they don't produce any vertex.

Not sure if I am explaining myself but all I want is to offset the top face. Any help will be appreciated as always.

Thanks!

[TIG]

Read my SmartOffset code to see how I offset the edges of a given face...

[tt_su]

Side note - Ruby is very slow. You'll find using the SketchUp API's .distance method much faster than doing your own length calculation. At least if you do this for a somewhat large set of entities.

[renderiza]

@tig said:

Read my SmartOffset code to see how I offset the edges of a given face...

That is by no means an easy task but I will try to understand what you wrote. Isn't there a 1st grader version?

@tt_su said:

Side note - Ruby is very slow. You'll find using the SketchUp API's .distance method much faster than doing your own length calculation. At least if you do this for a somewhat large set of entities.

That is good to know thanks!