How to Reverse a null object direction linked to another path ?

[brahimna7la]

Hi everyones , i'm trying to arows in after effects ;

after drawing the path and creating a null object (with trace path technique) for tracking the end of the path to add the arrow head to it ,

everything went well but i have the null object going to the opposite direction of  path and there is no reverse path direction like in standard shapes .

How can i reverse the direction of the null object (it's linked with expression to the other path ) ?

[Ossama5FE3]

Try to reverse the path direction before doing the trace path 

[Mylenium]

You can always adjust the expression to reference the correct anchor point or path keyframes. It's really not clear what you are actually doing as you are mixing up different things.

Mylenium

[ShiveringCactus]

Doesn't Trace Path give you a slider where you set the path percentage?  Is it not possible to animate the slider from 100 to 0 to reverse the path?