VOS Object Type Definition

property.extrapolated

OTD #021; Revision 0.

Group: property.

Extends: property

This type is an extension of property, which stores one or more floating point numbers, along with the "velocity" and "accelaration" of those values. Remote objects of this type can use the accelaration and velocity to calculate the "current position" over time. The standard property read interface should return the most recently calculated position values (always with a datatype of "text/x-vector").

Authors

Peter Amstutz, VOS/Interreality (http://www.interreality.org/~tetron) (tetron @ interreality . org)

Child Objects

this type expects no child objects.

Messages

 

extrapolated-property-set [accepts]

Set position, velocity and acceleration values.

Fields:

x (optional)

Set position to this value. Should contain a string of floating point numbers, seperated by whitespace.

dx (optional)

Set velocity to this value. Should contain a string of floating

ddx (optional)

Set acceleration to this value. Should contain a string of floating

t (optional)

Time step from which current position should be calculated using dx and ddx.

Replies:

 

extrapolated-property-update [update]

Notification of new extrapolation data. May also indicate errors with extrapolated-property-set.

Fields:

error (optional)

The presence of this field indicates that an error occured in acting on the message referred to by the "in-reply-to" field. In this condition, no other field will be present; usually they all are. The value of this field describes the error.

x (optional)

The new position.

dx (optional)

The new velocity.

ddx (optional)

The new acceleration.

t (optional)

Time step from which current position should be calculated using dx and ddx.

Replies:

 

start-listening [accepts]

Request from remote object to listen to changes in the local object.

Fields:

listen (optional)

This field must be "property.extrapolated" to get extrapolation updates.

Replies:

 

stop-listening [accepts]

Stop listening to this property.

Fields:

listen (optional)

Must be "property.extrapolated" to stop extrapolation updates.

Replies:

History of this document

Revision 0 (Sat Aug 10 10:23:28 EDT 2002):
Created -rh