ex_mesh.rb

#####################################################
#  ex_mesh.rb
#  by Brad Denniston   Copyright (c) 2014
#
#  Demonstrate PolygonMesh methods
#
#  THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
#   IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
#   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
#####################################################

module Mesh

  # create global variables
  #
  def self.reset
    $inst1 = nil
    $inst2 = nil
    $inst3 = nil
    $face = nil
    $mesh = nil
    $mesh2 = nil
    $pts = Array.new
  end

  # cubecomp - build 3 cubes
  #
  def self.cubecomp
    points = Array.new
    points[0] = ORIGIN
    points[1] = [10,0,0]
    points[2] = [10,10,0]
    points[3] = [0,10,0]
	
    # create a component definition for the cube
    new_comp_def = Sketchup.active_model.definitions.add("Cube size 10")
	
    # create a face instance
    newface = new_comp_def.entities.add_face(points)
	
    # extend the face in the component definition into a cube
    # If the z face is pointing up, reverse it.  
    newface.reverse! if newface.normal.z < 0
    newface.pushpull 10   # now this is the cube is defined
	
    # an instance must be placed at some location, transform it
    trans0 = Geom::Transformation.new # an empty, default transformation. 
	
    # Create an instance of the Cube component. 
    act_ents = Sketchup.active_model.active_entities
    new_inst_index = act_ents.size - 1
    act_ents.add_instance(new_comp_def, trans0)
    $inst1 = act_ents[new_inst_index]
    trans1 = Geom::Transformation.new([4,4,4])
    $inst2 = act_ents.add_instance(new_comp_def, trans1)
    $inst3 = act_ents.add_instance(new_comp_def, trans1)
  end

  # makeAface
  #
  def self.makeAface
    $mesh1 = Geom::PolygonMesh.new
    $mesh2 = Geom::PolygonMesh.new
    $pts[0] = ORIGIN
    $pts[1] = [10,0,0]
    $pts[2] = [10,10,0]
    $pts[3] = [0,10,0]
	
    # Add the face to the entities in the model
    entities = Sketchup.active_model.active_entities
    $face = entities.add_face($pts)
    p "The face is #{$face}" # shows all 4 edges
    # to_s is no different
    # to_a is not defined
    print "\n"
   end

  # all_connected
  #
  def self.all_connected
    connected = $face.all_connected
    p "connected is #{connected}" # shows all edges
    # to_a same as just connected.
    print "\n"
  end

  # makePolyMesh
  #
  def self.makePolyMesh
    index = $mesh1.add_polygon( $pts )
    p "mesh1 index is #{index}"
    # p "Mesh1 is #{$mesh1[index]}" so what does the index mean?
    print "\n"
  end

  # count_points
  #
  def self.count_points
    index = $mesh2.add_polygon( $pts )
    $pts[4] = [15,15,0]
    $mesh2.add_point($pts[4]) # 5 sided
    num = $mesh2.count_points
    p "mesh2 point count is #{num}"
    print "\n"
  end

  # faceToMesh
  #
  def self.faceToMesh
    $mesh1 = $face.mesh(7)
    p "mesh1 is now #{$mesh1}"
    print "\n"
  end

  # point_at
  #
  def self.point_at
    p "$mesh1 point at index 1 is #{$mesh1.point_at(1)}"
    p "$mesh1 point at index 2 is #{$mesh1.point_at(2)}"
    p "$mesh1 point at index 3 is #{$mesh1.point_at(3)}"
    p "$mesh1 index of point at [0,10,0] is #{$mesh1.point_index($pts[3])}"
    p "and $mesh1 points are #{$mesh1.points}"
    print "\n"
  end

  self.reset
  self.makeAface
  self.all_connected
  self.makePolyMesh
  self.count_points
  self.point_at

end #module