millenniumWAVE technologies

Also See:

Quote of the Month

This Month's Quote

INTRODUCTION

THE source for information, the industry bible so to speak, is the VRML 2.0 Sourcebook, Andrea L. Ames, David Nadeau, John Moreland, Wiley and Sons, N.Y. 1997, ISBN 0-471-16507-7 See http://www.wiley.com/compbooks/, get the book/CD!

Other sources of info include the Annotated VRML 97 Reference, fully online at http://www.best.com/~rikk/Book/book.shtml. Excellent resource.

FEATURES OF VRML 2.0

• animations of objects
• sound and movie files
• viewer interaction
• time and proximity sensors
• scripting with Java

Samples of code may be seen below, and simple worlds can be viewed from Scotty's VR WAVE, VRML 2.0 samples.

VRML files may contain:

• The file header ( for VRML 2.0: #VRML V2.0 utf8), required
• Comments: notes to make code readable, begins with pound sign (#)
• Nodes: elements of scene information, (such as shapes, or transformations)
• Fields: node attributes you can change, (all have default values)
• Values: attributes of fields
• Defined node names: names for reusable nodes
• Sensors: used to sense touch, time, proximity to change elements in world
• Interpolators: used to animate objects or properties based on time (keyframing)
• Routes: used to connect sensors and interpolators to object or property nodes
• Prototypes: self-designed objects and properties
• Scripts: Java applets and Javascripts for interactivity and animation

NOTES

• there may be mistakes (hard to believe, eh?), so please bear with me as I capture them. Please email me at mascott@igs.net if you have any suggestions, bug reports, etc., I will be most appreciative.
• any text editor can be used, save file with the .WRL extension
• VRML is case sensitive, spaces and carriage returns do not count
• VRML uses the concept of generic units for measurement, any measurement can be described as long as it is consistent, (i.e. meters, feet, micrometers, light years, etc.).
• angles are measured in radians, rad = (degrees/180)*PI, 180° = 3.14159 rad
• colors specified in RGB fractional units from 0.0 to 1.0 (0.0, 0.0, 0.0 = black, 1.0, 1.0, 1.0 = white)
• the order of fields (property or attribute settings) within a node is unimportant
• defaults exist for all fields. PLEASE NOTE: you do not need any fields if you are using the default.
• default values are shown below. Please not that values such as NULL don't do a hell of a lot.
• objects will be automatically embedded in each other if created at same space. VRML v1.0 and v2.0 use the orthogonal system (X, Y, Z coordinates, right hand rule). To place a node other than at 0,0,0, you move and/or rotate (transform) the axis first
• generally, you set properties such as materials or colors, than create the node(s) to use those properties
• groups are nodes used to isolate axis, transformation or property changes. Keeping the global coordinates is easier than trying to keep track of where you are at any point in your code.

ROUTES AND EVENTS (Advanced)

Most nodes have input and output jacks that you can wire. Input jacks are called eventIn, output jacks are called eventOut. Implicit input and output jacks are called exposed fields. With this ability, it is necessary to know which elements, or fields can be changed. To denote this, the fields in various nodes are noted as "exposed field". This means you can cause a change in a field parameter during the viewing of a world. At the risk of making the code look overly complex, I have noted these field parameters, as well as the field values. This will help you determine the values required in a field. (EventIns and eventOuts have to have matching field values). The field values are either SF (single field value), MF (multiple field value). Please note that anything preceding a # is a comment and not necessary in your code.

Field Values

SFBool	Boolean TRUE or FALSE
SFColor/MFColor	3 floating point values for color eg. 1.0 1.0 1.0
SFFlot/MFFloat	floating point decimal numbers
SFImage	list of color values for surface texture
SFInt32/MFInt32	32 bit integers
SFNode/MFNode	VRML node like Sphere
SFRotation/MFRotation	3 axis values, one rotation angle in radians
SFString/MFString	characters in quotation marks
SFTime	floating point value, time (sec) since 70.01.01 12:00am.
SFVEc2f/MFVec3f	2 value 2D floating point vector
SFVec3f/MFVec3f	3 value 3D floating point vector

Beam me up, Scotty!

FILE INFORMATION

VRML 2.0 HEADER (req'd at top of all files)

WORLD INFORMATION (optional)

WorldInfo {

	title	" "	# field SFString, used for title bar
	info	[" "]	# field MFString, strings of information

}

NODES

Nodes such as shapes and transforms (all called children) are grouped, in nodes such as the Group node, the Shape nodes, the Transform nodes. This keeps properties and transformations contained within the group, nodes outside the group are unaffected. Groups can be nested. Children can be parents to other children nodes. The top level parent is the root.

GROUP NODES

Group

{

	children	[ enter nodes here ]	# exposedField MFNode
	bboxCenter	0.0 0.0 0.0	# field SFVec3f
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f
	addChildren		# eventIn MFNode
	removeChildren		# eventIn MFNode

}

Billboard {

	children	[ enter nodes here ]	# exposedField MFNode
	axisOfRotation	0.0 1.0 0.0	# exposedField SFVec3f
	bboxCenter	0.0 0.0 0.0	# field SFVec3f
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f
	addChildren		# eventIn MFNode
	removeChildren		# eventIn MFNode

}

Used to keep shapes toward viewer no matter which angle they are coming from. (Z axis always toward viewer). AxisofRotation default rotates around Y axis, like billboard sign. Value of 0.0, 0.0, 0.0 would allow rotation in any angle. Instanced defined Billboard groups act independently.

Switch {

	whichChoice	-1	# exposedField SFInt32
	choice	[ nodes for each selection ]	# exposedField MFNode

}

Switch allows separate groups or nodes to be imaged. WhichChoice selects which group of nodes to image.

Anchor { # links Web pages and worlds to objects

	children	[ ]	# exposedField MFNode
	url	[" "]	# exposedField MFString, priority list
	parameter	[ ]	# exposedField MFString
	description	" "	# exposedField MFString, usually displayed at cursor
	bboxCenter	0.0 0.0 0.0	# field SFVec3f
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f
	addChildren		#eventIn MFNode
	removeChildren		#eventOut MFNode

}

SHAPE NODE

Shape #used for all shapes

{

	appearance	NULL	exposedField SFNode
	geometry	NULL	exposedField SFNode

}

PROPERTY NODES

Appearance { # placed in appearance field in Shape node

	material	NULL	# see Material below
	texture	NULL	# see textures below
	textureTransform	NULL	# see TextureTransform below

}

Material { # placed in material field in Appearance node

	ambientIntensity	0.2	# exposedField SFFloat
	diffuseColor	0.8 0.8 0.8	# exposedField SFColor, main shading color
	emissiveColor	0.0 0.0 0.0	# exposedField SFColor, glowing color
	specularColor	0.0 0.0 0.0	# exposedField SFColor, color of reflection highlight
	shininess	0.2	# exposedField SFFloat
	transparency	0.0	# exposedField SFFloat

}

ImageTexture { # used in texture field in Appearance node

	url	[" "]	# exposedField MFString
	repeatS	TRUE	# field SFBool
	repeatT	TRUE	# field SFBool

}

MovieTexture { # used in texture field in Appearance node

	loop	FALSE	# exposedField SFBool
	speed	1.0	# exposedField SFFloat
	startTime	0.0	# exposedField SFTime
	stopTime	0.0	# exposedField SFTime
	url	[" "]	# exposedField MFString
	repeatS	TRUE	# field SFBool
	repeatT	TRUE	# field SFBool
	duration_changed		# eventOut SFFloat
	isActive		# eventOut SFBool

}

PixelTexture { # used in texture field in Appearance node

	image	0.0 0.0 0.0	# exposedField SFImage
	repeatS	TRUE	# field SFBool
	repeatT	TRUE	# field SFBool

}

TextureTransform { # used in texture field in Appearance node

	translation	0.0 0.0	# exposedField SFVec2f
	rotation	0.0	# exposedField SFFloat
	scale	1.0 1.0	# exposedField SFVec2f
	center	0.0 0.0	# exposedField SFVec2f

}

PRIMITIVE GEOMETRY NODES

Box {

size

2.0 2.0 2.0

# field SFVec3f

}

Sphere {

radius

1.0

# field SFFloat

}

Cylinder {

	radius	1.0	# field SFFloat
	height	2.0	# field SFFloat
	bottom	TRUE	# field SFBool
	side	TRUE	# field SFBool
	top	TRUE	# field SFBool

}

Cone {

	height	2.0	# field SFFloat
	bottomRadius	1.0	# field SFFloat
	side	TRUE	# field SFBool
	bottom	TRUE	# field SFBool

}

Text {

	string	[ ]	# exposedField MFString, separate strings with commas
	fontStyle	NULL	# exposedField SFNode
	maxExtent	0.0	# exposedField SFFloat
	length	[ ]	# exposedField MFFloat, lengths for each individual string

}

FontStyle { # (a property node for the Text node above)

	family	"SERIF"	# field SFString
	horizontal	TRUE	# field SFBool
	justify	"BEGIN"	# field MFString
	language	" "	# field SFString, use of English recommended for compatibility
	leftToRight	TRUE	# field SFBool
	size	1.0	# field SFFloat
	spacing	1.0	# field SFFloat
	style	"PLAIN"	# field SFString
	topToBottom	TRUE	# field SFBool

}

TRANSFORM NODE

{

	translation	0.0 0.0 0.0	# exposedField SFVec3f
	rotation	0.0 0.0 1.0 0.0	# exposedField SFRotation
	center	0.0 0.0 0.0	# exposedField SFVec3f
	scale	1.0 1.0 1.0	# exposedField SFVec3f
	scaleOrientation	0.0 0.0 1.0 0.0	# exposedField SFRotation
	bboxCenter	0.0 0.0 0.0	# field SFVec3f, bounding box: used for render culling
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f
	children	[ #enter nodes here ]

}

Beam me up, Scotty!

ADVANCED GEOMETRY NODES (Coordinate Geometry Nodes)

Use the following sets in the geometry field of Shape node, as in:

geometry IndexFaceSet {
coord Coordinate {

point

[ # enter XYZ coordinate list ]

}
}

PointSet {

	color	NULL	# exposedField SFNode
	coord	NULL	# exposedField SFNode

}

IndexedLineSet {

	color	NULL	# exposedField SFNode
	coord	NULL	# exposedField SFNode
	coordIndex	[ ]	# field MFInt32
	colorIndex	[ ]	# field MFInt32
	colorPerVertex	TRUE	# field SFBool
	set_coordIndex		# eventIn MFInt32
	set_colorIndex		# eventIn MFInt32

}

IndexedFaceSet {

	color	NULL	# exposedField SFNode
	coord	NULL	# exposedField SFNode
	normal	NULL	# exposedField SFNode
	texCoord	NULL	# exposedField SFNode
	ccw	TRUE	# field SFBool
	colorIndex	[ ]	# field MFInt32
	colorPerVertex	TRUE	# field SFBool
	convex	TRUE	# field SFBool
	coordIndex	[ ]	# field MFInt32
	creaseAngle	0.0	# field SFFloat
	normalIndex	[ ]	# field MFInt32
	normalPerVertex	TRUE	# field SFBool
	solid	TRUE	# field SFBool
	texCoordIndex	[ ]	# field MFInt32
	set_colorIndex		# eventIn MFInt32
	set_coordIndex		# eventIn MFInt32
	set_normalIndex		# eventIn MFInt32
	set_texCoordIndex		# eventIn MFInt32

}

ElevationGrid {

	color	NULL	# exposedField SFNode
	normal	NULL	# exposedField SFNode
	texCoord	NULL	# exposedField SFNode
	height	[ ]	# field MFFloat
	ccw	TRUE	# field SFBool
	colorPerVertex	TRUE	# field SFBool
	creaseAngle	0.0	# field SFFloat
	normalPerVertex	TRUE	# field SFBool
	solid	TRUE	# field SFBool
	xDimension	0.0	# field SFInt32
	xSpacing	0.0	# field SFFloat
	zDimension	0.0	# field SFInt32
	zSpacing	0.0	# field SFFloat
	set_height		# eventIn MFFloat

}

The following are fields for the coordinate geometry nodes:

Color { # used in color field of coord geometry nodes

color

[ ]

# exposedField MFColor (list of colors)

}

TextureCoordinate { # used in the texCoord field in IndexFaceSet, ElevationGrid

point

[ ]

# exposedField MFVec2f

}

Normal { #used in normal field of IndexFaceSet and ElevationGrid

vector

[ ]

# exposedField MFVec3f

} #can be used with NormalInterpolator node

ADVANCED GEOMETRY NODES (Extrusion Nodes)

Extrusion {

	beginCap	TRUE	# field SFBool
	ccw	TRUE	# field SFBool
	convex	TRUE	# field SFBool
	creaseAngle	0.0	# field SFFloat
	crossSection	[ 1.0 1.0,1.0 -1.0, -1.0 -1.0,-1.0 1.0, 1.0 1.0 ]	# field MFVec2f
	endCap	TRUE	# field SFBool
	orientation	[ 0.0 0.0 1.0 0.0 ]	# field MFRotation
	scale	[ 1.0 1.0 ]	# field MFVec2f
	solid	TRUE	# field SFBool
	spine	[ 0.0 0.0 0.0, 0.0 1.0 0.0 ]	# field MFVec3f
	set_crossSection		# eventIn MFVec2f
	set_orientation		# eventIn MFRotation
	set_scale		# eventIn MFVec2f
	set_spine		# eventIn MFVec3f

}

DEFINING AND INSTANCING NODE NAMES AND INLINING FILES

DEF name node-type {…..}

# name can be composed of letters, numbers, underscores. Case sensitive, cannot start with numbers.

USE name

Inlining is used for inserting separate VRML files such as furniture in a room or rooms in a building.

Inline {

	url	[ "name.wrl" ]	# exposedField MFString
	bboxCenter	0.0 0.0 0.0	# field SFVec3f
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f

}

BACKGROUND NODES

Background {

	skyColor	[ 0.0 0.0 0.0 ]	# exposedField MFColor
	skyAngle	[ ]	# exposedField MFFloat
	groundColor	[ ]	# exposedField MFColor
	groundAngle	[ ]	# exposedField MFFloat
	backUrl	[ ]	# exposedField MFString
	bottomUrl	[ ]	# exposedField MFString
	frontUrl	[ ]	# exposedField MFString
	leftUrl	[ ]	# exposedField MFString
	rightUrl	[ ]	# exposedField MFString
	topUrl	[ ]	# exposedField MFString
	set_bind		# eventIn SFBool
	bind_changed		# eventOut SFBool

}

Fog {

	color	1.0 1.0 1.0	# exposedField SFColor
	visibilityRange	0.0	# exposedField SFFloat
	fogType	"LINEAR"	# exposedField SFString, else EXPONENTIAL
	set_bind		# eventIn SFBool
	bind_changed		# eventOut SFBool

}

Beam me up, Scotty!

CONTROLLING VIEWPOINT

The ViewPoint node specifies the location of the viewer "eyes", takes the place of cameras. NavigationInfo provides info on the viewer's avatar, or virtual self, and how it navigates using the current viewpoint.

Viewpoint {

	position	0.0 0.0 1.0	# exposedField SFVec3f
	orientation	0.0 0.0 1.0 0.0	# exposedField SFRotation
	fieldOfView	0.785398	# exposedField SFFloat
	description	" "	# field SFString
	jump	TRUE	# exposedField SFBool
	set_bind		# eventIn SFBool
	isBound		# eventOut SFBool
	bindTime		# eventOut SFTime

}

NavigationInfo {

	type	"WALK"	# exposedField MFString
	speed	1.0	# exposedField SFFloat
	avatarSize	[ 0.25, 1.6, 0.75 ]	# exposedField MFFloat
	headlight	TRUE	# exposedField SFBool
	visibilityLimit	0.0	# exposedField SFFloat
	set_bind		# eventIn SFBool
	isBound		# eventOut SFBool

}

LIGHTING

DirectionLights are lights are lights aimed from infinity so that rays are parallel, like the Sun. PointLight emanates in a radial pattern in all directions, like a light bulb. SpotLights are light constrained in a cone from the light source. Normal lighting is accomplished with the headlight, a white DirectionLight that is automatic and is aimed from your viewpoint. This can be truned off with the NavigationInfo node.

Note: In VRML, objects do not cast shadows. Faked shadows are used sometimes for realism. Note also that there are some limitations in different browsers, such as how a light will look and how many lights can be in any scene.

DirectionalLight {

	on	TRUE	# exposedField SFBool
	intensity	1.0	# exposedField SFFloat
	ambientIntensity	0.0	# exposedField SFFloat
	color	1.0 1.0 1.0	# exposedField SFColor
	direction	0.0 0.0 -1.0	# exposedField SFVec3f

}

PointLight {

	on	TRUE	# exposedField SFBool
	location	0.0 0.0 0.0	# exposedField SFVec3f
	radius	100	# exposedField SFFloat
	intensity	1.0	# exposedField SFFloat
	ambientIntensity	0.0	# exposedField SFFloat
	color	1.0 1.0 1.0	# exposedField SFColor
	attenuation	1.0 0.0 0.0	# exposedField SFVec3f

}

SpotLight {

	on	TRUE	# exposedField SFBool
	location	0.0 0.0 0.0	# exposedField SFVec3f
	direction	0.0 0.0 -1.0	# exposedField SFVec3f
	radius	100	# exposedField SFFloat
	intensity	1.0	# exposedField SFFloat
	ambientIntensity	0.0	# exposedField SFFloat
	color	1.0 1.0 1.0	# exposedField SFColor
	attenuation	1.0 0.0 0.0	# exposedField SFVec3f
	beamWidth	1.570796	# exposedField SFFloat
	cutOffAngle	0.785398	# exposedField SFFloat

}

SOUND

Sound in VRML 2.0 is 3D, the sound will seem to emanate from different locations in the world. Sound formats include General MIDI type 1 or WAV.

Sound {

	source	NULL	# exposedField SFNode
	intensity	1.0	# exposedField SFFloat
	location	0.0 0.0 0.0	# exposedField SFVec3f
	direction	0.0 0.0 1.0	# exposedField SFVec3f
	minBack	1.0	# exposedField SFFloat
	minFront	1.0	# exposedField SFFloat
	maxBack	10.0	# exposedField SFFloat
	maxFront	10.0	# exposedField SFFloat
	priority	0.0	# exposedField SFFloat
	spatialize	TRUE	# field SFBool

}

AudioClip # used in source field in Sound node

{

	url	[" "]	# exposedField MFString
	duration	" "	# exposedField SFString
	startTime	0.0	# exposedField SFTime
	stopTime	0.0	# exposedField SFTime
	pitch	1.0	# exposedField SFFloat
	loop	FALSE	# exposedField SFBool
	isActive		# eventOut SFBool
	duration_changed		# eventOut SFFloat

}

LEVEL OF DETAIL

You can set the level of detail seen from a distance, used to speed up rendering. Levels refer to shapes or url's of shapes, listed in order from highest detail to lowest.

LOD {

	center	0.0 0.0 0.0	# field SFVec3f
	level	[ ]	# exposedField MFNode, shapes from high detail to low
	range	[ ]	# field MFFloat, distance in units, n-1 number of levels

}

Beam me up, Scotty!

SENSOR NODES

Sensors are used for animations or viewer interactions. Note that fields without values are IMPLICIT, meaning you do not put them in your code, they are there. See route examples to see how they are used.

TimeSensor {

	enabled	TRUE	# exposedField SFBool
	cycleInterval	1.0	# exposedField SFTime, sets cycle time
	loop	FALSE	# exposedField SFBool
	startTime	0.0	# exposedField SFTime, rarely used
	stopTime	0.0	# exposedField SFTime, rarely used
	isActive		# eventOut SFBool
	time		# eventOut SFTime
	cycleTime		# eventOut SFTime
	fraction_changed		# eventOut SFFloat, mainly used

}

Time Sensors are used to output to interpolators which then change a node's position, rotation or scale. The time sensor is a clock used to generate and control animations. Enabled turns clock on/off. CycleInterval in seconds, is time to take fractional time from 0.0 to 1.0. This is what you use to describe the length of animation. Loop TRUE makes continuous loop. StartTime is absolute time in seconds to begin clock after 12:00 midnight GMT, Jan. 1, 1970 (birth of UNIX!) StopTime ends clock. Both are used infrequently except to start/stop animations by other interpolators. IsActive generates TRUE when sensor becomes active. Time outputs absolute time continuously when sensor active. CycleTime outputs time whenever cycle starts, or begins loops. Fraction_changed outputs fractional value between 0.0 and 1.0 till end of cycleInterval, and at again at beginning of each loop.

TouchSensor {

	enabled	TRUE	# exposedField SFBool
	isActive		# eventOut SFBool
	isOver		# eventOut SFBool, mouse cursor overtop?
	touchTime		# eventOut SFTime
	hitNormal_changed		# eventOut SFVec3f
	hitPoint_changed		# eventOut SFVec3f
	hitTexCoord_changed		# eventOut SFVec2f

}

TouchSensor is used to sense a viewer's mouse (or other pointer's) movement over a node, clicking on a node and/or dragging the node. A TouchSensor will affect any shape within it's group. Multiple sensors is allowable in a group. The innermost sensor in a nest of groups overrides the outer ones, (i.e. an on/off switch can be used on a movable object). Other notes:

autoOffset: when TRUE remembers last position, default.

Enabled: can be changed to start or stop animation or motion

hitPoint: the point at which the viewer points at the shape

max and minPosition: limits movement, can be used to constrain motion, i.e. if min = max

The following three nodes act similar to the Touch Sensor, but are used to pick up and move shapes within a world:

PlaneSensor: moves shape in plane, like floor or wall

SphereSensor: moves shape around axis, like surface of ball

CylinderSensor moves shape around center axis, like record player or rolling pin

The CylinderSensor will look like a turntable if viewing from above, like a roller viewed from side.

PlaneSensor {

	autoOffset	TRUE	# exposedField SFBool
	enabled	TRUE	# exposedField SFBool
	isActive		# eventOut SFBool
	maxPosition	-1.0 -1.0	# exposedField SFVec2f, maximum XY coordinates
	minPosition	0.0 0.0	# exposedField SFVec2f, minimum XY coordinates
	offset	0.0 0.0 0.0	# exposedField SFVec3f
	trackPoint_changed		# eventOut SFVec3f
	translation_changed		# eventOut SFVec3f

}

SphereSensor {

	autoOffset	TRUE	# exposedField SFBool
	enabled	TRUE	# exposedField SFBool
	isActive		# eventOut SFBool
	offset	0.0 1.0 0.0 0	# exposedField SFRotation
	rotation_changed		# eventOut SFRotation
	trackPoint_changed		# eventOut SFVec3f

}

CylinderSensor {

	autoOffset	TRUE	# exposedField SFBool
	diskAngle	0.262	# exposedField SFFloat, (15 degrees)
	enabled	TRUE	# exposedField SFBool
	isActive		# eventOut SFBool
	maxAngle	-1.0	# exposedField SFFloat
	minAngle	0.0	# exposedField SFFloat
	offset	0.0	# exposedField SFFloat
	rotation_changed		# eventOut SFRotation
	trackPoint_changed		# eventOut SFVec3f

}

The ProximitySensor detects viewer cursor position. The Collision group node detects when a viewer collides with an object such as a wall.

ProximitySensor {

	enabled	TRUE	# exposedField SFBool
	center	0.0 0.0 0.0	# exposedField SFVec3f
	size	0.0 0.0 0.0	# exposedField SFVec3f
	isActive		# eventOut SFBool
	position_changed		# eventOut SFVec3f
	orientation_changed		# eventOut SFRotation
	enterTime		# eventOut SFTime
	exitTime		# eventOut SFTime

}

Collision {

	children	[ ]	# exposedField MFNode
	collide	TRUE	# exposedField SFBool
	bboxCenter	0.0 0.0 0.0	# field SFVec3f
	bboxSize	-1.0 -1.0 -1.0	# field SFVec3f
	proxy	NULL	# field SFNode
	collideTime		# eventOut SFTime
	addChildren		# eventIn MFNode
	removeChildren		# eventIn MFNode

}

VisibilitySensor {

	center	0.0 0.0 0.0	# exposedField SFVec3f
	enabled	TRUE	# exposedField SFBool
	size	0.0 0.0 0.0	# exposedField SFVec3f
	isActive		# eventOut SFBool
	enterTime		# eventOut SFTime
	exitTime		# eventOut SFTime

}

ANIMATION INTERPOLATION NODES

Interpolators take info from sensors and route it to nodes. PositionInterpolator sets position (translates), or scales (shrinks/enlarges), OrientationInterpolator sets rotation angles. ColorInterpolator changes RGB colors. ScalarInterpolator outputs a scalar value that can be used to set transparency, time values, or anything else that requires or uses one value. Interpolators are usually placed at end of the file, just before routing information.

PositionInterpolator {

	key	[ # enter key fields here ]	# exposedField MFFloat
	keyValue	[ # enter key position value fields here ]	# exposedField MFVec3f
	set_fraction		# eventIn SFFloat, implicit
	value_change		# eventOut SFVec3f, implicit

}

OrientationInterpolator {

	key	[ # enter key fields here ]	# exposedField MFFloat
	keyValue	[ # enter key rotation value fields here ]	# exposedField MFRotation
	set_fraction		# eventIn SFFloat
	value_changed		# eventOut SFRotation

}

ColorInterpolator { #note: interpolates HSV values for smooth color shift

	key	[ # enter keys here ]	# exposedField MFFloat
	keyValue	[ # enter key RGB color values here ]	# exposedField MFColor
	set_fraction		# eventIn SFFloat
	value_changed		# eventOut SFColor

}

ScalarInterpolator {

	key	[ # enter keys here ]	# exposedField MFFloat
	keyValue	[ # enter key values here ]	# exposedField MFVec3f
	set_fraction		# eventIn SFFloat
	value_changed		# eventOut SFFloat

}

CoordinateInterpolator {

	key	[ # enter keys here ]	# exposedField MFFloat
	keyValue	[ # enter key values here ]	# exposedField MFVec3f
	set_fraction		# eventIn SFFloat
	value_changed		# eventOut MFVec3f

}

NormalInterpolator {

	key	[ # enter keys here ]	# exposedField MFFloat
	keyValue	[ # enter key values here ]	# exposedField MFVec3f
	set_fraction		# eventIn SFFloat
	value_changed		# eventOut MFVec3f

}

ROUTES

Routes describe the path of action from a sensor, to interpolator (if required), to shape node. For example, the following routes from a TimeSensor (Clock) to the OrientationInterpolator (GlobePath), to the rotation of a shape (Globe):

ROUTE Clock.fraction_changed TO GlobePath.set_fraction

ROUTE GlobePath.value_changed TO Globe.set_rotation

SCRIPTS

Scripts are Java or JavaScript apps used for creating more complex animations, etc. The Script node provides a shell for the programs.

Script {

	url	[" "]	# exposedField MFString
	mustEvaluate	FALSE	# field SFBool
	directOutput	FALSE	# field SFBool

# And any number of:

	field		# fieldType fieldName initialValue
	eventIn		# eventTypeName eventName
	eventOut		# eventTypeName eventName

}

Beam me up, Scotty!

EXAMPLES

EXAMPLE 1: Hello World!

#VRML V2.0 utf8

#a simple box

Shape

{

	appearance Appearance
	{
	material Material { }
	}
	geometry Box { }

}

EXAMPLE 2: A SIMPLE CYLINDER

#VRML V2.0 utf8

Shape {

	appearance Appearance {
	material Material { }
	}
	geometry Cylinder {
	height 2.0
	radius 1.5
	}

}

EXAMPLE 3: Multiple objects

#VRML V2.0 utf8

# crossed long boxes

# note commas between shape nodes

Group

{

	children
	[
Shape	{
	appearance DEF MyColor Appearance {
	material Material { }
	}
	geometry Box {size 25.0 2.0 2.0}
	},
Shape	{
	appearance USE MyColor
	geometry Box {size 2.0 25.0 2.0}
	},
Shape	{
	appearance USE MyColor
	geometry Box {size 2.0 2.0 25.0}
	}
	]

}

EXAMPLE 4: Animation using TimeSensor

#VRML V2.0 utf8

# The VRML 2.0 Sourcebook

# Copyright (c) 1997

# Andrea L. Ames, David R. Nadeau, and John L. Moreland

Group {

	children [
	# Rotating cylinder
	DEF Column Transform {
	rotation 0.0 0.0 1.0 0.0
		children Shape {
		appearance Appearance {
		material Material { }
		}
		geometry Cylinder {
		height 1.0
		radius 0.2
		}
		}
	},
	# Animation clock
	DEF Clock TimeSensor {
		cycleInterval 4.0
		loop TRUE
	},
	# Animation path
	DEF ColumnPath OrientationInterpolator {
		key [ 0.0, 0.50, 1.0 ]
		keyValue [
		0.0 0.0 1.0 0.0,
		0.0 0.0 1.0 3.14,
		0.0 0.0 1.0 6.28
		]
	}
	]

}

ROUTE Clock.fraction_changed TO ColumnPath.set_fraction

ROUTE ColumnPath.value_changed TO Column.set_rotation

Beam me up, Scotty

© 2003 millenniumWAVE technologies
Please acknowledge author in use of any original material