# Copyright (c) 2001, Stanford University
# All rights reserved
#
# See the file LICENSE.txt for information on redistributing this software.

# Test running a quad-buffered stereo-aware program in a passive stereo
# configuration.  Basically, instead of quad-color buffers, we use a tilesort
# config with two servers, one for the left eye, one for the right.

# This demo runs in two modes:
# 1. Native stereo (the default):
#      The stereocube demo will be run with the -s option which causes it
#      explicitly render left/right views with glDrawBuffer.
# 2. Forced stereo (pass in "force" parameter)
#      The stereocube demo runs as a normal, non-stereo program.
#      The config file here specifies special viewing and projection
#      matrices to produce a stereo effect.
#
# Two server windows will open, one for the left eye, one for the right.
# By either "defocusing" or crossing your eyes you can see the stere effect.
# The default window arrangement is for defocused stereo.
# You'll have to swap the default window positions to get cross-eyed stereo.
#
# You may also have to tune the EyeSep (interocular distance) and
# default tile/window size.


import sys
sys.path.append( "../server" )
from mothership import *
import crmatrix


FORCE_STEREO = 0
DEMO = "stereocube"

for arg in sys.argv[1:]:
	if arg == "-force":
		FORCE_STEREO = 1
	elif arg[0] != "-":
		DEMO = arg
		print "--> Note: you may have to tweak the projection parameters!"
	else:
		print "Unknown option %s" % arg
		sys.exit(1)

if FORCE_STEREO:
	print "--> Forcing %s into stereo mode via config file." % DEMO
else:
	print "--> Running %s in conventional stereo mode." % DEMO
	


if DEMO == "stereocube":
	# Parameters copied from sterecube.c demo
	if FORCE_STEREO == 0:
		DEMO += " -s"
	else:
		EyeSep = 0.3
		Width = 12.0
		Hither = 1.0
		Yon = 25.0
		FocalDist = 5.0
elif DEMO == "city":
	EyeSep = 0.3
	Width = 12.0
	Hither = 1.0
	Yon = 250.0
	FocalDist = 5.0
elif DEMO == "atlantis":
	# atlantis uses some really big numbers!
	# not a great demo for stereo, either.
	EyeSep = 0.3
	Width = 2000.0
	Hither = 10000.0
	Yon = 400000.0
	FocalDist = Hither * 2.0
elif DEMO == "paraview":
	# Note: seems to work with "blow.vtk" dataset
	EyeSep = 2.0
	Width = 40.0
	Hither = 120.0
	Yon = 180.0
	FocalDist = 150
else:
	# some default values that seem to work for some Mesa demos
	EyeSep = 0.3      # half of interocular distance
	Width = 2.0       # frustum width at FocalDist
	Hither = 1.0      # near clip plane distance from eye
	Yon = 250.0       # far clip plane distance from eye
	FocalDist = 4.0   # focal distance for stereo imaging
	

cr = CR()
cr.MTU( 1024*1024 )

TileWidth = 250
TileHeight = 250

tilesortspu = SPU("tilesort")
tilesortspu.Conf('bucket_mode', 'Test All Tiles')
tilesortspu.Conf('stereo_mode', 'Passive')
tilesortspu.Conf('scale_images', 1)

clientnode = CRApplicationNode( )
clientnode.StartDir( crbindir )
clientnode.SetApplication( DEMO )
clientnode.AddSPU( tilesortspu )

EyeNames = [ "left", "right" ]

# Loop over two eye views
for eye in range(2):
	renderspu = SPU( 'render' )
	renderspu.Conf( 'window_geometry', [eye*(TileWidth+10), 0, TileWidth, TileHeight] )
	renderspu.Conf( 'title', "%s view" % EyeNames[eye] )

	node = CRNetworkNode( )
	# Note: same tile bounds for both views/servers!
	node.AddTile( 0, 0, TileWidth, TileHeight )

	if FORCE_STEREO:
		# Set up left/right eye viewing transforms to impose upon a non-stereo
		# application:
		# 1. Specify a viewing matrix to achieve interocular translation.
		# 2. Specify a skewed projection frustum for each eye.

		# Arithmetic same as in sterecube.c demo
		aspect = float(TileWidth) / float(TileHeight)
		s = Hither / FocalDist
		halfWidth = 0.5 * Width
		top = s * halfWidth
		bottom = -top

		# View matrix
		v = crmatrix.CRMatrix()
		if eye == 0:
			v.Translate(+EyeSep, 0, 0)
		else:
			v.Translate(-EyeSep, 0, 0)
		node.Conf('view_matrix', v.ToList())

		# Projection matrix
		p = crmatrix.CRMatrix()
		if eye == 0:
			left = s * ((halfWidth * -aspect) - EyeSep);
			right = s * ((halfWidth * aspect) - EyeSep);
		else:
			left = s * (halfWidth * -aspect + EyeSep);
			right = s * (halfWidth * aspect + EyeSep);
		p.Frustum(left, right, bottom, top, Hither, Yon)
		node.Conf('projection_matrix', p.ToList())

	node.Conf('optimize_bucket', 0)  # just to be safe
	node.Conf('stereo_view', EyeNames[eye])
	node.AddSPU( renderspu )
	cr.AddNode( node )

	# Add the server, indicating whether it's for the left or right eye.
	# Actually, lefv vs. right doesn't matter if FORCE_STEREO is non-zero.
	tilesortspu.AddServer( node, protocol='tcpip', port=7000 + eye)


cr.AddNode( clientnode )

cr.Go()