WorldViz User Forum - Newbie - Trouble using loops

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Newbie - Trouble using loops

Hi all,

I'm new to using Vizard and am having difficulty using loops. My issue is that when I use a loop, it blocks the environment from being rendered. I thought that this was OK as I was using the same method I saw in the Vizard documentation.

Code:

import viz

import viztask



env = viz.add('../models/environment.OSGB')



viz.go()



def run():

        

        while True:

                # Something simple

                print viz.MainView.getPosition()

                print viz.MainView.getEuler()



viztask.schedule(run())

What I get here is just a black window. The model is never seen but the output window shows the camera Euler and position. I'm aware that the loop is blocking but how do I get around this?

Functions scheduled with viztask must contain a yield command. The following should work:

Code:

import viz

import viztask



env = viz.add('dojo.osgb')



viz.go()



def run():

        

        while True:

                # Something simple

                yield viztask.waitTime(1)

                print viz.MainView.getPosition()

                print viz.MainView.getEuler()



viztask.schedule(run())

Thanks for the quick reply.

Yep, that worked. I must ask though, why is this?

Using what you said, I have put the print statements in another function and I call that using a yield statement.

Vizard's task functions are implemented using Python generators which use yield statements.