Thanks Simeon,
It's great to finally see a full-blown experiment.
Thanks again, Eamon
On Jan 23, 2006, at 8:28 AM, Simeon Fitch wrote:
Eamon,
The Kubovy Lab @ UVa is doing what you describe (if I understand you correctly) by using multiple presentation/viewport instances for each component of each trial (all sharing the same screen). For example, in one experiment we present:
1) A fixation spot 2) A mask 3) The stimulus 4) A response screen
Each of these is a stimulus tied to a Presentation and Viewport. A "show()" convenience method has been added to each class to reset the Presentation object and call its "go()" method.
The inner "loop" of this experiment looks something like this: ---------------------------- # Define the trials conditions = setupTrialData(sequenceFileName) breakNotice = Instructions(screen, "Take a moment to rest.") for i, trial in enumerate(conditions): lattice.setTrial(trial) fixationPres.go() mask.show() lattice.show() response.show() logger.log(trial)
if ((i+1) % session.breakInterval) == 0: breakNotice.show() ------------------------------- The power of the Presentation object becomes apparent when you have Stimulus parameters which change over time (e.g. a function of 't') or between trials.
You are very welcome to download our source code and play with it however you like. Instructions are available here:
http://kubovylab.psyc.virginia.edu/index.php/ How_to_Get_The_Source_Code
For a quick sense on how we are using VisionEgg, some example screen shots are available here:
http://kubovylab.psyc.virginia.edu/index.php/Main_Page
Along with instructions on how to get it running, if interested:
http://kubovylab.psyc.virginia.edu/index.php/ Perception_Toolkit_Development_Environment_Setup
Good luck!
Simeon Fitch
-- Simeon H.K. Fitch, Owner Mustard Seed Software Charlottesville, VA 22901
On 1/23/06, Eamon Caddigan <ecaddiga@xxxxxxxx> wrote:Hi all,
Our lab is getting ready to run its first experiments that make use of Vision Egg. They work well enough, but I've been unable to make use of the Presentation class for my main loop without the result feeling uncomfortably kludgey.
I'm happy to write my own main loop. However, since the code I write now may be used by other people in the lab as we continue transitioning to Vision Egg, I want it to fall in line with the current best practices.
I'd probably feel better about this if the examples distributed with Vision Egg included a multi-trial experiment.
Thanks, Eamon Caddigan
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