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Height units and aspect ratio

Hello

I would like to present rectangular images (constant size) in an online study and would like to maintain their aspect ratio, while also be able to work out where the participant clicked on the image. Using Builder, I thought I could do this by setting units to “Height units” and defining the Size variable to say 0.8, which, in my understanding, should present an image with 80% window height and width automatically worked out for the particular screen. Instead, my images end up squares. Is that expected with setting units to “Height units” ?

Looking at https://www.psychopy.org/general/units.html, I’m confused over the sentence “This type of unit can be useful in that it scales with window size, unlike Degrees of visual angle or Centimeters on, but stimuli remain square, unlike Normalised units units.”

It says it scales with window size, but stimuli remain square… so does this mean it is ALWAYS square?

If you want a rectange then you could use a polygon (in height units) of e.g. (.4,.8) which will always be twice as tall as it is wide.

Stimuli remain square in height units if they are intended to be square.

Thank you, that makes perfect sense! I didn’t connect the dots that “height units” can be used for defining width…