damageeventtilerange 5879 5880 damageeventtilerange 6829 6843 damageeventtilerange 6876 6885 damageeventtilerange 6887 6890 damageeventtilerange 8497 8500 onevent EVENT_DAMAGEWALL ife wall[RETURN].picnum BLUEBALLVEND { sound VENT_BUST sound GLASS_BREAKING lotsofglass 20 setw[RETURN].picnum BLUEBALLBROKE } ife wall[RETURN].picnum SNACKVEND { sound VENT_BUST sound GLASS_BREAKING lotsofglass 20 setw[RETURN].picnum SNACKBROKE } ife wall[RETURN].picnum 6829 setw[RETURN].picnum W_TECHWALL1 ife wall[RETURN].picnum 6832 setw[RETURN].picnum W_TECHWALL2 ife wall[RETURN].picnum 6835 setw[RETURN].picnum W_TECHWALL15 ife wall[RETURN].picnum 6838 setw[RETURN].picnum W_TECHWALL4 ife wall[RETURN].picnum 6841 setw[RETURN].picnum W_TECHWALL16 ifge wall[RETURN].picnum 6876 ifle wall[RETURN].picnum 6890 { sound VENT_BUST sound GLASS_BREAKING lotsofglass 15 setw[RETURN].picnum 7445 } ifge wall[RETURN].picnum 8497 ifle wall[RETURN].picnum 8500 { sound VENT_BUST sound GLASS_BREAKING lotsofglass 15 setw[RETURN].picnum 7445 } endevent
Ok, this is a little messy, but I've pasted in the relevent code from Alien Armageddon so you can see how to do it. First, outside of any actors or events, you use the damageeventtilerange command to specify tile numbers that will be processed in EVENT_DAMAGEWALL.
In the event itself, RETURN is the wall number being hit by a weapon. The event code tells the game what to do when RETURN is hit. Notice in every case I am changing the picnum of the wall to the damaged version. In between, there is often some code spawning debris and such.
In some cases, I just changed the picnum to one of the hardcoded ones -- doing that will cause the wall to behave just like you had shot one of the hardcoded destructible ones, which is appropriate if the art on your custom tile fits.