text: ##########################################################################
  #  
  #  Copyright (c) 2012, John Haddon. All rights reserved.
  #  Copyright (c) 2013, Image Engine Design Inc. All rights reserved.
  #  
  #  Redistribution and use in source and binary forms, with or without
  #  modification, are permitted provided that the following conditions are
  #  met:
  #  
  #      * Redistributions of source code must retain the above
  #        copyright notice, this list of conditions and the following
  #        disclaimer.
  #  
  #      * Redistributions in binary form must reproduce the above
  #        copyright notice, this list of conditions and the following
  #        disclaimer in the documentation and/or other materials provided with
  #        the distribution.
  #  
  #      * Neither the name of John Haddon nor the names of
  #        any other contributors to this software may be used to endorse or
  #        promote products derived from this software without specific prior
  #        written permission.
  #  
  #  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  #  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  #  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  #  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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  #  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  #  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  #  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  #  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  #  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  #  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  #  
  ##########################################################################
  
  import unittest
  
  import Gaffer
  import GafferTest
  
  class TimeWarpComputeNodeTest( unittest.TestCase ) :
  
  	def test( self ) :
  	
  		s = Gaffer.ScriptNode()
  		
  		s["m"] = GafferTest.MultiplyNode()
  		s["m"]["op2"].setValue( 1 )
  		
  		s["e"] = Gaffer.Expression()
  		s["e"]["engine"].setValue( "python" )
  		s["e"]["expression"].setValue( "parent[\"m\"][\"op1\"] = int( context[\"frame\"] )" ) 
  		
  		s["w"] = Gaffer.TimeWarpComputeNode()
  		s["w"]["in"] = Gaffer.IntPlug()
  		s["w"]["in"].setInput( s["m"]["product"] )
  		s["w"]["out"] = Gaffer.IntPlug( direction = Gaffer.Plug.Direction.Out )
  		s["w"]["offset"].setValue( 2 )
  		s["w"]["speed"].setValue( 2 )
  		
  		for i in range( 0, 10 ) :
  			c = Gaffer.Context()
  			c.setFrame( i )
  			with c :
  				self.assertEqual( s["m"]["product"].getValue(), i )
  				self.assertEqual( s["w"]["out"].getValue(), i * 2 + 2 )
  	
  	def testHash( self ) :
  	
  		# we want the output of the time warp to have the same hash
  		# as the input at the appropriate point in time. that way we get
  		# to share cache entries between the nodes and use less memory
  		# and do less computation.
  		
  		s = Gaffer.ScriptNode()
  		
  		s["m"] = GafferTest.MultiplyNode()
  		s["m"]["op2"].setValue( 1 )
  		
  		s["e"] = Gaffer.Expression()
  		s["e"]["engine"].setValue( "python" )
  		s["e"]["expression"].setValue( "parent[\"m\"][\"op1\"] = int( context[\"frame\"] )" ) 
  					
  		s["w"] = Gaffer.TimeWarpComputeNode()
  		s["w"]["in"] = Gaffer.IntPlug()
  		s["w"]["in"].setInput( s["m"]["product"] )
  		s["w"]["out"] = Gaffer.IntPlug( direction = Gaffer.Plug.Direction.Out )
  		s["w"]["offset"].setValue( 2 )
  		
  		for i in range( 0, 10 ) :
  			c = Gaffer.Context()
  			c.setFrame( i )
  			with c :
  				self.assertEqual( s["m"]["product"].getValue(), i )
  				self.assertEqual( s["w"]["out"].getValue(), i + 2 )
  				wh = s["w"]["out"].hash()	
  			c.setFrame( i + 2 )
  			with c :
  				mh = s["m"]["product"].hash()
  			self.assertEqual( wh, mh )
  				
  if __name__ == "__main__":
  	unittest.main()
  