Building extruded shapes
slide.wrl

	

#VRML V2.0 utf8
#
#  Spiral slide
#  slide.wrl
#        by David R. Nadeau
#        published in "The VRML 2.0 Sourcebook" by Ames, Nadeau, and Moreland
#
#  Illustrate the use of an Extrusion to build a playground slide.
#

WorldInfo {
	title "Spiral slide"
	info [ "Copyright (c) 1997, Andrea L. Ames, David R. Nadeau, John L. Moreland" ]
}

Viewpoint {
	position 0.0 1.5 11.0
	description "Entry view"
}

NavigationInfo {
	type [ "EXAMINE", "ANY" ]
	headlight TRUE
}

Shape {
	appearance Appearance {
		material Material {
			diffuseColor 0.0 1.0 0.7
		}
	}
	geometry Extrusion {
		creaseAngle 1.57
		endCap   FALSE
		beginCap FALSE
		solid    FALSE
		crossSection [
		# Half-circle
			-1.00  0.00,  -0.92 -0.38,
			-0.71 -0.71,  -0.38 -0.92,
			 0.00 -1.00,   0.38 -0.92,
			 0.71 -0.71,   0.92 -0.38,
			 1.00  0.00,
		]
		spine [
		# Helix
			 2.00 0.00 -0.00,   1.85 0.12 -0.77,
			 1.41 0.24 -1.41,   0.77 0.36 -1.85,
			 0.00 0.48 -2.00,  -0.77 0.61 -1.85,
			-1.41 0.73 -1.41,  -1.85 0.85 -0.77,
			-2.00 0.97  0.00,  -1.85 1.09  0.77,
			-1.41 1.21  1.41,  -0.77 1.33  1.85,
			 0.00 1.45  2.00,   0.77 1.58  1.85,
			 1.41 1.70  1.41,   1.85 1.82  0.77,
			 2.00 1.94  0.00,   1.85 2.06 -0.77,
			 1.41 2.18 -1.41,   0.77 2.30 -1.85,
			 0.00 2.42 -2.00,  -0.77 2.55 -1.85,
			-1.41 2.67 -1.41,  -1.85 2.79 -0.77,
			-2.00 2.91  0.00,  -1.85 3.03  0.77,
			-1.41 3.15  1.41,  -0.77 3.27  1.85,
			 0.00 3.39  2.00,   0.77 3.52  1.85,
			 1.41 3.64  1.41,   1.85 3.76  0.77,
			 2.00 3.88  0.00,
		]
	}
}