Generally speaking, in VRML the shapes can be split into 2 groups: "ready-made" shapes, and author-defined shapes. The ready-made shape nodes are AsciiText, Cone, Cube, Cylinder, and Sphere. The author-defined shape nodes are IndexedFaceSet, IndexedLineSet, and PointSet. All shapes are affected by the current cumulative transformation and rotation values. All shapes are drawn using the most recent material definition. It is very easy for a shape to end up in the wrong place unless you carefully use Separator nodes. For info on the transformation and rotation nodes, see the Transformations topic. For info on the material nodes, see theMaterials and Separators topic.

AsciiText

The AsciiText node produces characters from the ASCII character set. You specify the text under the string parameter. The first line of text appears with it's baseline at (0,0,0), with additional strings drawn below, with y decreasing by size * spacing (the "size" value is set under the FontStyle node). The justification parameter is used to state wether the LEFT, RIGHT, or CENTER of the string is located at x = 0. The width parameter gives a suggested width for the text, and it's default value is the natural width of the string. A 0 for this parameter uses the natural width of the text.

Parameter	Default Value	Data Type
string	""	String
spacing	1.0	Float
justification	LEFT	Enumerated - LEFT | RIGHT | CENTER
width	0	Float

Example: drawing the word "hello".

AsciiText {
	string "hello"
}

Cone

This creates a cone with it's central axis lying along the y axis. The bottomRadius parameter sets the radius of the bottom of the cone. The height parameter sets the height, from apex to base, of the cone. The parts parameter defines which parts of the cone are drawn. The Cone is always drawn with it's center at (0,0,0), so use transformations and rotations to get it to where it is wanted. The apex of the cone is by default at the top (i.e. +ve y), and the default height is 2, making the base of the cone at y = -1.

Parameter	Default Value	Data Type
bottomRadius	1.0	Float
height	2.0	Float
parts	ALL	Enumerated - ALL | BOTTOM | SIDES

Example: a cone 0.5 units tall, and with radius of 2 (very flat!).

Cone {
	bottomRadius 2
	height 0.5
}

Cube

Creates a cuboid with each face parallel to one of the axes. The width, height, and depth parameters control the dimensions of the object. The cube will be centered at (0,0,0). The default dimensions of the cube are 2 in each dimension (i.e. from -1 to +1 in each direction). As with all objects, use transformations and rotations to get the cube where you want it.

Parameter	Default Value	Data Type
depth	2.0	Float
height	2.0	Float
width	2.0	Float

Example: A concrete slab (large and thin cuboid).

Cube {
	depth 10
	height 0.5
	width 10
}

Cylinder

This node creates a cylinder (or tube) centered on the y axis. The height parameter defines the height of the cylinder (or length of the tube). The radius parameter defines the radius of the cylinder (or how fat the tube is). The parts parameter selects which parts of the cylinder are to be draw, selecting from SIDES, TOP, BOTTOM, and ALL. The TOP will be the "cap" at the positive y end. The cylinder is drawn centered at (0,0,0), and has a default height of 2 (i.e. from y = -1 to y = +1), and default radius of 2.

Parameter	Default Value	Data Type
height	2.0	Float
parts	ALL	Enumerated - ALL | BOTTOM | SIDES | TOP
radius	1.0	Float

Example: a coin (a very flat, wide cylinder).

Cylinder {
	height 0.1
	radius 2
}

Sphere

Draws a sphere (or ball) centered at (0,0,0). The radius parameter specifies the radius of the sphere. Obviously, a sphere does not look differant if rotated, so a single transformation is all that is needed to get it into the desired position.

Parameter	Default Value	Data Type
radius	1.0	Float

Example: a marble.

Sphere {
	radius 0.4
}

Coordinate3

Defines a series of points in 3-dimensional space, for use with one of methods below. You should note that this node doesn't actually produce any visable result, but must be used with IndexedFaceSet, IndexedLineSet, or PointSet to actually draw a shape. The first coordinate has in index of 0, the 2nd has an index of 1 etc. The last coordinate therefore has an index of (n - 1). If you use this node more than once, then upon reaching the second occurance, all the points in the first set will be replaced by those in the second set, not appended to. The first set is therfore lost. Remember that if you are defining more that one point, you must enclose the list in square brackets.

Parameter	Default Value	Data Type
point	0 0 0	MVector3D

Example: Define the coordinates of a triangle.

Coordinate3 {
	point [0 0 0, 1 2 0, 2 0 0]
}

IndexedFaceSet

This node is arguably the most useful of the 3 available author-defined shapes. This node builds a set of polygon faces using the coordinates defined in the Coordinate3 node. You achieve this by specifying the corners of each polygon, using the index of the point as defined in the Coordinate3 node. To end each polygon, use an index of -1. For example, to build a face from the 1st, 2nd, 8th, and 11th points as defined in a Coordinate3 declaration, you would add this line under the coordIndex parameter :
coordIndex [0, 1, 7, 10, -1]
There are 3 other parameters that can be used with this node, but they are excluded here, basically because they are not that important or useful.

Parameter	Default Value	Data Type
coordIndex	0	MLong

Example: Draw the triangle defined in Coordinate3.

Coordinate3 {
	point [0 0 0, 1 2 0, 2 0 0]
}

IndexedFaceSet {
	coordIndex [0, 1, 2, -1]
}

IndexedLineSet

Similar to IndexedFaceSet, except that instead of producing faces/polygons, this produces "polylines". This basically means a wire-frame version of what IndexedFaceSet produces. Apart from it's name, the node has exactly the same parameters, and behaves in the same way. Again, three unimportant and relatively complicated parameters have been left out.

Parameter	Default Value	Data Type
coordIndex	0	MLong

Example: Draw a wire-frame version of the triangle drawn above.

Coordinate3 {
	point [0 0 0, 1 2 0, 2 0 0]
}

IndexedLineSet {
	coordIndex [0, 1, 2, -1]
}

PointSet

I can't think of any useful purpose for this node, and under the Netscape plugin, it produces no visable output. This node represents a set of points at the coordinates in the most recent Coordinate3 statement. The startIndex parameter defines the index of the first point to plot. The numPoints parameter defines how many points are to be plotted. A value of -1 here uses all the available points.

Parameter	Default Value	Data Type
startIndex	0	Long
numPoints	-1	Long

Example: Plot the corners of the triangle.

Coordinate3 {
	point [0 0 0, 1 2 0, 2 0 0]
}

PointSet {
	startIndex 0
	numPoints -1
}

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