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wimartin
07-07-2014, 11:53 AM
Hey Forum,

First time posting, please forgive the newbie question.

I have an experiment written in Vizard where subjects have to move forward a particular distance. Once they reach the end of the distance, I calculate how far they traveled using the vizmat.distance command. However, in an earlier version of this experiment, I didn't use vizmat.distance, but still collected data, and now I'd like to see if I can go back and infer what distance they were traveling, based on the speed they were moving and how long the trial was. However, this is trickier than I thought, because I'm not sure what unit the speed value is.

For this, I use the CameraHandler module, borrowed from the tutorial here: http://docs.worldviz.com/vizard/#examples/viewpointCameraControl.htm?Highlight=camera

At the bottom of that tutorial "def _camUpdate( self, e ):" is what I use for moving the camera viewpoint. Under there is something called e.view.move, where the speed is specified. Does anyone know what e.elapsed is? Is this meters per second, or some other amount of time? Any help would be appreciated, thanks!

~Martin

Jeff
07-07-2014, 02:31 PM
The e.elapsed value represents the time elapsed since the last frame. This is multiplied against a constant value to determine the distance moved each frame in meters. The value passed to e.view.move is the amount to move relative to the current position. It is not a speed. Does this help?