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Depth modulated grating

PostPosted: Fri Jan 20, 2012 12:26 pm
by alexwade
Is it possible to use depth modulation in a custom stimulus .For example, to generate a sine wave grating that is modulated in depth as well as luminance? I have tried setting z=sin(x/10); D=sin(x/10) for example in the custom stim box but it doesn't seem to produce an effect. I'm using side-by-side stereo.
thanks

Alex

Re: Depth modulated grating

PostPosted: Fri Jan 20, 2012 3:42 pm
by psykinematix
Yes, it is possible to specify a depth modulation in a custom stimulus: however the left and right components have to be created separately using the 'L=' and 'R=' prefixes for their x coordinates, and the depth modulation of a carrier stimulus should be created by specifying a disparity envelop and calling the dshiftp(carrier,disparity) function (the left and right versions having then disparity envelops with opposite sign).

We attached an example that we will add as a demo in the next version of Psykinematix.

Note that the 'D=' format can only be used to specify a global disparity and only used in the x coordinate field!

–– The Psykinematix Support Team