crash on viz.waittime

[vadrian]

i have a script that's too complicated to copy here but generally does this:

iterates through 4 scenes
object iterates through a list of data
object makes callbacks to functions I provide
one of the callbacks makes a viz.director(showNextInstructions) call

def showNextInstructions():
	global exp, instructions, infoBox
	global DELAY_BEFORE_INSTRUCTIONS, DELAY_AFTER_INSTRUCTIONS
	print "showing instructions"
	# delay before showing instructions
	print "\tdelay"
	viz.waittime(DELAY_BEFORE_INSTRUCTIONS)
	print "\tmoving infobox to current scene"
	scene = exp.get(vhil.CURRENT_SEQUENCE)+STARTING_SCENE
	infoBox._group.parent(viz.SCREEN,scene)
	#infoBox = vizinfo.add(instructions.pop(0))
	print "\tpoping next instruction"
	infoBox.message(instructions.pop(0))
	#infoBox.translate(0.5,0.95)
	#infoBox.bgcolor(viz.WHITE,1.0)
	#infoBox.bordercolor(viz.BLACK, 1.0)
	print "\tshowing box"
	infoBox._group.visible(1)
	infoBox.expand()

i know, its a mess, but with the print calls, i can tell that the crash happens on viz.waittime(DELAY_BEFORE_INSTRUCTIONS)

not only that, it happens at the same place in the script ONLY SOMETIMES. It's wierd, but sometimes the script runs without a hitch, with crashes only happening randomly in about 1 out of 5 runthroughs.

no python/vizard errors, just the windows "fatal error" window, and then closes the program.

please help. this is for an experiment, so its imperative that there are no crashes (or else we lose all the subject's data)


thanks

adrian

[farshizzo]

Hi,

Adding objects inside a director function is currently unstable. I believe this may be the cause of your problem. If it is possible, I would recommend that you use a timer instead.

[vadrian]

but i don't make any new objects in that function. unless infoBox._group.parent() or infoBox.message() make a new objects, i can't see where the program can have threading/concurrency errors.

(the only object creating line is commented out because it never worked as intended due to setting the scene of vizinfo boxes)

[farshizzo]

Hi,

Does commenting out the line infoBox._group.parent(viz.SCREEN,scene) prevent the crash? The parent command removes the object then re-adds it to another. This would be the same is adding an object.

[vadrian]

yup, you're right as usual!