UP Deck tries to evaluate anything enclosed in square brackets. When a deck button is pressed, math expressions are evaluated before the actions are sent to OBS.
Example - if you have defined values $stream_width, $stream_height and $margin (see setting custom values), then you could position an object near the top right of the screen by using;
Place object near top right
x=[ $stream_width - $margin ]
y=[ $margin ]
As well as the standard math operators for addition, subtraction, multiplication and division (+, -. *, /), all of the functions listed in the Corona Math Library will also work.
Eample - update a text object with a random number between 5 and 10.
Update text source with random number
text=[ random(5, 10) ]
When used with loops, this functionality allows you to create some more complex animations without having to write a lot of individual button commands.