[open] PsychoPy Rotation and DotLife

misspmasquith

Hi

My question refers to the coder view and elementarraystim in Psychopy.

The visual stimulus that I require moves radially inwards and outwards, and rotates as it moves (like a twisting motion). It is an optic flow stimulus.
I have created the radial flow, but I can't work out how to make the dots rotate.
Any advice / equation would be well received!

Also, I want to make each of the dots have a random dot life between 1 and 100, then on each frame decrement the dot life of every dot. Then I am trying to search for any that have a dot life of zero and change the corresponding (x,y) values to new random values and reset the dot life back to 100 - but I am having difficulty implementing this. Again any help would be much appreciated.

Thanks,

Phoebe

sebastiaan

Hi Phoebe,

What exactly do you have right now? Could you post/ upload the relevant script, or the entire experiment?

Cheers,
Sebastiaan

ainsley

Hi

I've used the following code, to get the dots to move outward from the center, how can I adjust it so they move inwards

for frameN in range(300):
    # update radius
    dotsRadius = (dotsRadius+speed)
    # random radius where radius too large
    outFieldDots = (dotsRadius>=fieldSize)
    dotsRadius[outFieldDots] = numpy.random.rand(sum(outFieldDots))*fieldSize
    dotsX, dotsY = pol2cart((dotsTheta),(dotsRadius))
    dots.setXYs(numpy.array([dotsX, dotsY]).transpose())
    dots.draw() 
    win.flip()

Thanks,
Ainsley

eduard

Hey Ainsley,

Would you mind providing a functioning example? I'm sure that the part that you posted earlier does indeed make the dots move outward. However, the more general part of the code is missing (initialization of the window, setting up the parameters, etc. ). Before I can start playing around with the code, I would need to spend time to make your example work. It would be easier if you could just post as much of your code as necessary to make your code executable by anyone.

Thanks,

Eduard