Variably assign button anchor position in builder

Builder
1

I have a series of response stimuli spaced evenly around a semicircle. I am trying to flip four of them (the lower two pairs in the screenshots) in the x-axis. I set it up to do so by participant, which works as written in my code chunks so far.

I ran into an issue, however, in that, since I’ve set the distances to the nearest inside point for the default position (see first screenshot), just flipping the x-axis value doesn’t give the desired output (see second screenshot.

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While I can set the button position through a variable, it doesn’t appear that I can variably assign the anchor for the buttons.

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Is there a way to do so that I’m not aware of? Is there a better way to approach the whole thing?

2

Wouldn’t it be better to anchor to the centre so it doesn’t move when flipped?

3

This had crossed my mind, but since I’d done the math to align the innermost point of each square to be the same distance from the center of the red box, I’d hoped to avoid having to re-do the math (as pes and mis are aligned on corner and the others on edge).

If that’s what I must do, no problem. I was just hoping to have missed an easier command.