Make buildings only buildable at trees?

[Yours Truly]

It's like the Haunted Gold Mine being able only to be built at Gold Mines. Are there are any ways we could make this stuff happen? Thanks,in advance.

 

[Nowow]

I don't know if you can actually build on trees, but I think you can go around it using a modified "force of nature" spell followed by a triggered "ivory tower" spell or something.

 

[Wietlol]

There is no real way to restrict a structure to be built on trees, but you can check if you ordered the unit to build it on a tree.

• Build Tower Restriction
  • Events
    • Unit - A unit Is issued an order targeting a point
  • Conditions
    • (Issued order) Equal to (Order(Tower))
  • Actions
    • Set TempBoolean = False
    • Set TempLocation = (Target point of issued order)
    • Destructible - Pick every destructible within 32.00 of TempLocation and do (Actions)
      • Loop - Actions
        • -------- check if picked destructable is tree --------
        • Set TempBoolean = True
    • If (All Conditions are True) then do (Then Actions) else do (Else Actions)
      • If - Conditions
        • TempBoolean Equal to False
      • Then - Actions
        • Trigger - Turn off (This trigger)
        • Unit - Pause (Triggering unit)
        • Unit - Order (Triggering unit) to Stop
        • Unit - Unpause (Triggering unit)
        • Trigger - Turn on (This trigger)
        • Set TempForce = (Player group((Triggering player)))
        • -------- This building has to be built on a tree. --------
        • Game - Display to TempForce the text: This building has t...
        • Custom script: call DestroyForce(udg_TempForce)
      • Else - Actions
    • Custom script: call RemoveLocation(udg_TempLocation)

Be sure to set "Pathing - Placement Requires (upap)" to none.
Also, this only checks if it is placed on anydestructable, you might want to download a system that is able to tell the difference between trees and other destructables.