VRML data types are used by VRML nodes to define objects and types of data that can appear in the VRML node fields and events.
This section explains these VRML field data types and VRML data class types.
The Simulink® 3D Animation™ product provides an interface between the MATLAB® and Simulink environment and VRML scenes. With this interface, you can set and get the VRML scene node field values. To work with these values, you must understand the relationship between VRML data types and the corresponding MATLAB data types. The following table illustrates the VRML data types and how they are converted to and from MATLAB types.
For a detailed description of the VRML fields, refer to the VRML97 Standard.
|VRML Type||Description||Simulink 3D Animation Type|
Boolean value true or false.
32–bit, floating-point value.
32–bit, signed-integer value.
Absolute or relative time value.
Vector of two floating-point values that you usually use for 2-D coordinates. For example, texture coordinates.
Single array (1-by-2)
Vector of three floating-point values that you usually use for 3-D coordinates.
Single array (1-by-3)
Vector of three floating-point values you use for RGB color specification.
Single array (1-by-3)
Vector of four floating-point values you use for specifying rotation coordinates (x, y, z) of an axis plus rotation angle around that axis.
Single array (1-by-4)
Two-dimensional array represented by a sequence of floating-point numbers.
uint8 array (n-by-m-by-3)
String in UTF-8 encoding. Compatible with ASCII, allowing you to use Unicode® characters.
Container for a VRML node.
Single array (n-by-1)
Single array (n-by-2)
Single array (n-by-3)
Single array (n-by-3)
Single array (n-by-4)
The Simulink 3D Animation software can work with various MATLAB data types, converting them if necessary:
The inputs for the
(and its dot notation form) and VR Sink and VR Source blocks, accept
all meaningful data types on input. Both convert the data types into
natural VRML types as necessary. The data types include logicals,
signed and unsigned integers, singles, and doubles.
getfield function (and its
dot notation form) return their natural data types according to the
To ensure backward compatibility with existing models and applications,
use the Simulink 3D Animation
to define the data type support. Their names are as follows:
A node can contain four classes of data:
eventOut. These classes define the behavior
of the nodes, the way the nodes are stored in the computer memory,
and how they can interact with other nodes and external objects.
|VRML Data Class||Description|
An event that can be received by the node
An event that can be sent by the node
A private node member, holding node data
A public node member, holding node data
eventIn events correspond to a field
in the node. Node fields are not accessible from outside the node.
The only way you can change them is by having a corresponding
Some nodes have
eventIn events that do not
correspond to any field of that node, but provide additional functionality
for it. For example, the Transform node
addChildren eventIn. When this event is
received, the child nodes that are passed are added to the list of
children of a given transform.
You use this class type for fields that are exposed to other objects.
This event is sent whenever the value of a corresponding node field that allows sending events changes its value.
You use this class type for fields that have this functionality.
A field can be set to a particular value in the VRML file. Generally,
the field is private to the node and its value can be changed only
if its node receives a corresponding
is important to understand that the field itself cannot be changed
on the fly by other nodes or via the external authoring interface.
You use this class type for fields that are not exposed and
do not have the
This is a powerful VRML data class that serves many purposes.
You use this class type for fields that have both
The alternative name of the corresponding
always the field name with a
set_ prefix. The name
eventOut is always the field name with a
exposedField class defines how the corresponding
exposedField classes, when an event occurs,
the field value is changed, with a corresponding change to the scene
appearance, and an
eventOut is sent with the new
field value. This allows the chaining of events through many nodes.
exposedField class is accessible to scripts,
field class is not.