Calculation

i am not sure if this is the right thread ( if not someone please move it to the right one , says help and info here)

what i wanted to ask if i use a skill like Explosive Spear , is the damage calculated when i throw it or after the fuse explodes?

What i am getting at is , if i take the passive node that gives bonus dmg while i am surrounded, and throw the spear , but before the fuse goes of i am no longer surrounded , does the explosion still get the bonus damage?