Animation Path File Format

The Animation Path File Format is a simple XML file for storing a set of points representing a path through space with a view direction.  It can be used, for example, to represent the motion of the position and orientation of a camera in the real or virtual world.

The contents of the file have the following structure:

X, Y are geographic coordinates, commonly known as longitude and latitude.  The attribute <p1> represents where the location is, and <p2> represents where it is looking.  The vector from <p1> to <p2> is the view direction.

Z is the elevation of each point, in meters.

The Datum of the coordinates is implicitly WGS84.  If you don't know what a Datum is, you can generally ignore this consideration.

The expected file extension for Animation Path files is .vtap

Limitations

This format does not encode every aspect of real-world cameras - such as field of view, roll, focal length, aspect ratio, etc.  This is a deliberate design decision, in order to keep the format simple and allow the receiving environment to control these parameters by itself.  However, if desired, one could easily add attributes (on the the <location> element) for additional parameters, and the result would remain compatible with applications that expect standard Animation Path files.

Sample File

mamane_street.vtap is a simple animation path with a locations.

Library Support

The vtlib library provides support for reading and writing Animation Path files, adding and removing locations, and automatically converts to and from the coordinate system of your terrain.  The class vtAnimPath provides this functionality.