Changes in 2.2.34 (Mar 2, 2023)
+ The option to set the pixels per degree to that of the central one degree
rather than the average across the entire screen is added. This is useful
for getting more accurate stimulus size and coordinates, when the subject
screen is larger than 20 degrees.
https://monkeylogic.nimh.nih.gov/docs_MainMenu.html#AdjustedPPD
+ A new property, AllowEarlyFix, is added to WaitThenHold, FreeThenHold and
MultiTarget. Its value is true, by default. When it is false, the adapters
stop as soon as the scene starts, if the XY tracker is already inside the
fixation window.