Transforming picked face

Developers Ruby API
4

Hello,
I have reference Dezmo post the code which has use in

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)
       @dist = 0.3.m
       # Vector X-axes, Y-axes, Z-axes,
	   @tvec = Geom::Vector3d.new([@dist, 0, 0])  # Vector X-axes
    if @face
       #@face.pushpull @dist, false,      # work properly
       Sketchup.active_model.entities.transform_entities(Geom::Transformation.translation(@tvec),@face.parent)
       # face transforming but something wrong
    end
    view.invalidate
	view.refresh
  end

  def draw(view)
    if @face
      loop = @face.outer_loop.vertices.map{|v|
        v.position.transform( @tr )
      }
      view.drawing_color = [255,20,147, 75] 
      view.draw(GL_POLYGON, loop)
    end
  end
end
Sketchup.active_model.select_tool(Testtool.new)

please check and revert
thanks