Help in distance measuring

[Null]

How do I make the condition: If the distance between the position of a unit and the position of the ability being casted is bigger/smaller than X

 

[Devalut]

And it would look something like this:

• Untitled Trigger 001
  • Events
  • Conditions
  • Actions
    • Set VariableSet X = 500.00
    • Set VariableSet Point[1] = (Position of (Triggering unit))
    • Set VariableSet Point[2] = (Position of (Picked unit))
    • If (All Conditions are True) then do (Then Actions) else do (Else Actions)
      • If - Conditions
        • (Distance between Point[1] and Point[2]) Greater than X
      • Then - Actions
      • Else - Actions
    • Custom script: call RemoveLocation(udg_Point[1])
    • Custom script: call RemoveLocation(udg_Point[2])