# Copyright 2005, Didier Bur

# Permission to use, copy, modify, and distribute this software for 
# any purpose and without fee is hereby granted, provided that the above
# copyright notice appear in all copies.

# 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.

# Name :          su2stl.rb 1.0
# Description :   Exports selection or whole model to STL format external file
# Author :        Didier Bur
# Usage :         Select objects exports the selection, no selection exports whole 
#                 model. Select Plugins/Export to STL. Groups and components not supported.
#                 
# Date :          27.June.2005
# Type :          Exporter
# History:        1.0 (27.June.2005) - first version
#                 1.1 (29.June.2005) - Bugs fixed, new messages.


#---------------------------------------------------------------------------------
def export_model_to_stl

#Init
model = Sketchup.active_model
ss = Sketchup.active_model.selection
model.start_operation "Export to STL"
faces_array = []
entities = model.entities

# Selection checking
if ss.empty? 
  answer = UI.messagebox("Nothing selected. Export whole model ?", MB_YESNOCANCEL)
  else
  entities_to_export = Sketchup.active_model.selection
end

if( answer == 6 )
  entities_to_export = model.entities
end

if( answer == 6 ) or (not ss.empty?)
# Delete any previously created STL triangles
(delete_stl_triangles)

# Output file
out_name = UI.openpanel( "Select file to export to", "." , "*.stl" )
export_file = File.new( out_name , "w" )
# Error checking, put valid elements in faces_array
others = 0
i = 0
0.upto(entities_to_export.length - 1) do |something|
  element = entities_to_export[i]
  if( element.typename != "Face")
    others = others + 1
  else
  faces_array.push element
  end
  i = i + 1
end  #of upto

# Layer management
model.layers.add("STL_triangles")
model.active_layer = ("STL_triangles")

#Triangulation
faces_array.each do |face|
  mesh=face.mesh(7)
  normal = mesh.normal_at 1
  Sketchup.active_model.entities.add_faces_from_mesh mesh, 9
end

#Collect triangles and export
(collect_stl_triangles)
(export_stl_triangles export_file)

#Report message
UI.messagebox( faces_array.length.to_s + " faces to export.\n" + others.to_s + " objects ignored.\n" + $triangles_array.length.to_s + " triangles exported to STL solid.")
$triangles_array = []

end #of if( answer == 6)

# Undo
model.commit_operation
end

def collect_stl_triangles
model = Sketchup.active_model
$triangles_array = []
entities = model.entities
i = 0
entities.each do |that|
  element = entities[i]
  if(element.typename == "Face" and element.layer.name == "STL_triangles")
    $triangles_array.push element
  end
  i = i + 1
end
end

def delete_stl_triangles
model = Sketchup.active_model
ent_arr=[]
model.entities.each do |element|
  if(element.layer.name == "STL_triangles")
  ent_arr.push element
  end
end
ent_arr.each {|e| e.erase! if not e.deleted?}
end

def export_stl_triangles( export_file )
model = Sketchup.active_model
#File Header
model_filename = File.basename(model.path)
if( model_filename == "" )
  model_filename = "no_name"
end
model_name = model_filename.split(".")[0]
export_file.puts( "solid " + model_name)
i = 0

$triangles_array.each do |tri|
  normal = tri.normal
  vertices = tri.vertices
  export_file.puts( "facet normal " + tri.normal[0].to_s + " " + tri.normal[1].to_s + " " + tri.normal[2].to_s)
  export_file.puts( "   outer loop")
  export_file.puts( "      vertex " + vertices[0].position.x.to_f.to_s + " " + vertices[0].position.y.to_f.to_s + " " + vertices[0].position.z.to_f.to_s)
  export_file.puts( "      vertex " + vertices[1].position.x.to_f.to_s + " " + vertices[1].position.y.to_f.to_s + " " + vertices[1].position.z.to_f.to_s)
  export_file.puts( "      vertex " + vertices[2].position.x.to_f.to_s + " " + vertices[2].position.y.to_f.to_s + " " + vertices[2].position.z.to_f.to_s)
  export_file.puts( "   endloop")
  export_file.puts( "endfacet")
  i = i + 1
  done = ((i * 100.0) / $triangles_array.length).to_i
  Sketchup.set_status_text("Exporting triangles: " + done.to_s + "%")
end
export_file.puts( "endsolid " + model_name)
# Close the export file:
export_file.close
end

#---------------------------------------------------------------------------------
# Menu items
if( not file_loaded?("su2stl.rb") )
  add_separator_to_menu("Plugins")
  UI.menu("Plugins").add_item("Export to STL") { export_model_to_stl }

end

#-----------------------------------------------------------------------------
file_loaded("su2stl.rb")