#!/usr/bin/env python

# Copyright (C) 2002-2003 Gideon May (gideon@computer.org)
#
# Permission to copy, use, sell and distribute this software is granted
# provided this copyright notice appears in all copies.
# Permission to modify the code and to distribute modified code is granted
# provided this copyright notice appears in all copies, and a notice
# that the code was modified is included with the copyright notice.
#
# This software is provided "as is" without express or implied warranty,
# and with no claim as to its suitability for any purpose.

# -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield 
#
# This application is open source and may be redistributed and/or modified   
# freely and without restriction, both in commericial and non commericial applications,
# as long as this copyright notice is maintained.
# 
# This application is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#

import sys
import math
from PyOSG import *
from OpenGL.GL import *

def  main(argv ):
    # use an ArgumentParser object to manage the program arguments.
    arguments = osg.ArgumentParser(argv)

    # set up the usage document, in case we need to print out how to use this program.
    arguments.getApplicationUsage().setDescription(arguments.getApplicationName()+" is the example which demonstrates how to use multi-pass and state inheritance to create a scribed rendered effect.")
    arguments.getApplicationUsage().setCommandLineUsage(arguments.getApplicationName()+" [options] filename ...")
    arguments.getApplicationUsage().addCommandLineOption("-h or --help","Display this information")
   
    # construct the viewer.
    viewer = osgProducer.Viewer(arguments)

    # set up the value with sensible default event handlers.
    viewer.setUpViewer(osgProducer.Viewer.STANDARD_SETTINGS)

    # get details on keyboard and mouse bindings used by the viewer.
    viewer.getUsage(arguments.getApplicationUsage())

    # if user request help write it out to cout.
    if arguments.read("-h") or arguments.read("--help"):
    
        arguments.getApplicationUsage().write()
        return 1
    

    # any option left unread are converted into errors to write out later.
    arguments.reportRemainingOptionsAsUnrecognized()

    # report any errors if they have occured when parsing the program aguments.
    if arguments.errors():
    
        arguments.writeErrorMessages()
        return 1
    
    
    if arguments.argc()<=1:
    
        arguments.getApplicationUsage().write(osg.ApplicationUsage.COMMAND_LINE_OPTION)
        return 1
    

    # load the nodes from the commandline arguments.
    loadedModel = osgDB.readNodeFiles(arguments)
    if not loadedModel:
    
        return 1
    
  
    # to do scribe mode we create a top most group to contain the
    # original model, and then a second group contains the same model
    # but overrides various state attributes, so that the second instance
    # is rendered as wireframe.
    
    rootnode = osg.Group()

    decorator = osg.Group()
    
    rootnode.addChild(loadedModel)
    
    
    rootnode.addChild(decorator)
    
    decorator.addChild(loadedModel);  

    # set up the state so that the underlying color is not seen through
    # and that the drawing mode is changed to wireframe, and a polygon offset
    # is added to ensure that we see the wireframe itself, and turn off 
    # so texturing too.
    stateset = osg.StateSet()
    material = osg.Material()
    polyoffset = osg.PolygonOffset()
    polyoffset.setFactor(-1.0)
    polyoffset.setUnits(-1.0)
    polymode = osg.PolygonMode()
    polymode.setMode(osg.PolygonMode.FRONT_AND_BACK,osg.PolygonMode.LINE)
    stateset.setAttributeAndModes(material,osg.StateAttribute.OVERRIDE|osg.StateAttribute.ON)
    stateset.setAttributeAndModes(polyoffset,osg.StateAttribute.OVERRIDE|osg.StateAttribute.ON)
    stateset.setAttributeAndModes(polymode,osg.StateAttribute.OVERRIDE|osg.StateAttribute.ON)
    stateset.setMode(GL_LIGHTING,osg.StateAttribute.OVERRIDE|osg.StateAttribute.OFF)
    stateset.setTextureMode(0,GL_TEXTURE_2D,osg.StateAttribute.OVERRIDE|osg.StateAttribute.OFF)
    
#     osg.LineStipple* linestipple = osg.LineStipple
#     linestipple.setFactor(1)
#     linestipple.setPattern(0xf00)
#     stateset.setAttributeAndModes(linestipple,osg.StateAttribute.OVERRIDE_ON)
    
    decorator.setStateSet(stateset)
  
    
    # run optimization over the scene graph
    optimzer = osgUtil.Optimizer()
    optimzer.optimize(rootnode)
     
    # add a viewport to the viewer and attach the scene graph.
    viewer.setSceneData( rootnode )
    
    # create the windows and run the threads.
    viewer.realize()

    while not viewer.done():
    
        # wait for all cull and draw threads to complete.
        viewer.sync()

        # update the scene by traversing it with the the update visitor which will
        # call all node update callbacks and animations.
        viewer.update()
         
        # fire off the cull and draw traversals of the scene.
        viewer.frame()
        
    
    
    # wait for all cull and draw threads to complete before exit.
    viewer.sync()

    return 0

if __name__ == "__main__":
    main(sys.argv)