scrollTrigger

udlr UDLR
|||| |||+- Scroll right
|||| ||+-- Scroll left
|||| |+--- Scroll down
|||| +---- Scroll up
|||+------ Check right bounds (0 = yes, 1 = no)
||+------- Check left bounds (0 = yes, 1 = no)
|+-------- Check lower bounds (0 = yes, 1 = no)
+--------- Check upper bounds (0 = yes, 1 = no)