Highlight the selection of a face

Developers Ruby API
1

Hello everyone,
I would like to highlight the selection of a face, with the mouse click on the face,
while I use “Class: Sketchup::Tool”, you can give me some advice, thank you.

Joseph.

2

You could use the .selection method to clear and add the face to the current_selection.
OR entirely within your own tool you could use the various draw method to add a temporary highlighted edge and/or a face.
Class: Sketchup::View — SketchUp Ruby API Documentation
Class: Sketchup::View — SketchUp Ruby API Documentation
etc…

3

Thanks for the answer, I tried to look at the code, but I could not understand much, you can further help more specific… thank you very much.

Joseph.

4 
# Inside your tool class ...

  def onLButtonUp(flags, x, y, view)
    model = view.model
    ph = view.pick_helper
    ph.do_pick(x, y)
    face = ph.picked_face
    model.selection.add(face) unless face.nil?
  end
1 Like
5

Just a quick snippet.

class Testtool
  def initialize
    @face = nil
    @tr = IDENTITY
  end

  def get_trans(ph, obj)
    ph.count.times{|i|
      if ph.leaf_at(i) == obj
        return ph.transformation_at(i)
      end
    }
    IDENTITY
  end

  def onMouseMove(flags, x, y, view)
    ph_fe = view.pick_helper
    ph_fe.do_pick(x, y, 0)
    face = ph_fe.picked_face
    @face = face ? face : nil
    @tr = get_trans( ph_fe, face ) if face
    view.invalidate
  end

  def onLButtonUp(flags, x, y, view)
    if @face
      @c_face = @face 
      @c_tr = @tr
      puts "#{@c_face} outer loop is highlighted."
    end
    view.invalidate
  end

  def draw(view)
    if @face
      loop = @face.outer_loop.vertices.map{|v|
        v.position.transform( @tr )
      }
      view.drawing_color = [0,0,256, 64] 
      view.draw(GL_POLYGON, loop)
    end
    if @c_face
      c_loop = @c_face.outer_loop.vertices.map{|v|
        v.position.transform( @c_tr )
      }
      view.line_width = 3
      view.drawing_color ="blue" 
      view.draw(GL_LINE_LOOP, c_loop)
    end
  end
end
Sketchup.active_model.select_tool(Testtool.new)
2 Likes
6

Dan, Can you please explain what is a drawback if I just use unless face instead?

7

Many thanks to all the participants, to the discussion, for their help…

Joseph.

8

None. No drawback. (In fact, likely faster as method calls take time.)
Just me being “picky”. (pun intended)

The docs actually do not say what is returned when the pickhelper cannot pick a face. (I assumed it would be nil.)

9

Thanks Dan, You reassured me.

In this case yes, it says : “Returns nil if there were no faces picked.”
However it is not in the right place (in Returns field), but above the example :confused:

1 Like
10

I stand corrected. :slight_smile:

1 Like
11

6 posts were split to a new topic: Transforming picked face