VRED - Virtual Reality Editor - PI-VR GmbH

3.19. TRACKING 3. USER INTERFACE
3.19.2 Coordinate Systems
The main difficulty with tracking lays within the three different
coordinate systems that have to be considered:
• Scene coordinate system. This is the coordinate
system of your virtual world, that is the scene loaded
into VRED. Note that all virtual representation of
bodies must be transform nodes. These use a local
coordinate system that is determined by the product
of all transform nodes above itself.
• Tracking coordinate system. The tracking coordinate
system belongs to the tracking hardware. This
coordinate system may be the same as the physical
coordinate system of your application, but it may
also be completely different, concerning both the
origin and the orientation.
• Physical coordinate system. The physical coordinate
system is that of the real world and is normally
defined by your needs (e.g. where the origin is and
the orientation).
The difficult task is to get these three coordinate systems
working together. Fortunately VRED has some built-in
capabilities to calibrate the coordinate systems to easily
change the origin or orientation. But still, you - as the
user - have to be aware of what you are doing and how
the coordinate systems should be mapped on each other.
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