So now i tried to make a custom weapon. i pick a unit ( i chose battlecruiser since it has 2 diff weapons), look at the combat tab and see that i can add more that two weapons on this unit. i also see a turret (though Battlecruiser doesn't have one).
Before you get ahead of yourself, there are a few things you need to consider. Any unit can have multiple weapons, but adding more than one weapon means that you have to actually set parameters for each weapon. For example, one of the BC's weapons only shoots air units while the other only shoots ground units. If you add another weapon to that, you will have to modify the existing weapons so it doesn't conflict. If you add another weapon that attacks ground units, you will have to set it up so that there is a reason for the BC to use that weapon instead of the normal ground-hitting weapon. For example, you could make it so that the normal ground weapon only hits enemies up to range 3 away from the BC, but this third weapon hits enemies from range 3 to range 5 or something. Or maybe you can have the third weapon only target mechanical units and set the existing weapon to target biological units. Either way, you have to make sure they don't conflict.
i don't want to edit the default weapon,
You will have to edit one or both of them if you plan on adding a third weapon.
so i have to duplicate, the question is, what part should i duplicate? i assume the effect - damage part was necessary to duplicate but what of the others?
If you're trying to add a third weapon as opposed to replacing one of the two, do not duplicate anything. Create the weapon from scratch. If you're going to just replace one of the existing weapons, you might as well just edit the weapon since it wont be used for anything else anyway. If you insist on duplicating, just duplicate the weapon, and as you go down the list and find what you need to change, duplicate those specific parts later on (like the damage effect).
i tried duplicating the ATA battery wpn (with effect: damage and launch missile duped) replaced it to the default battlecruiser weapon, test then it fires but no sound and it seems it lacks effect like the battlecruiser should at least emit some burst when it fires a weapon, (i think i added an area damage on it and the battlecruiser itself gain damage from its attack if the target was right next to it)
Like Ahli said, each weapon needs an "Action" Actor that controls the sounds, impact actors, impact effects, and launch effects. Without that, you wont see missiles, hear explosions, see explosions, or deal damage when the missile hits. I really suggest starting from scratch.
on the weapon tab i just copy the Duke's Revenger Cannons then paste, i see a Duke's Revenger Cannons Copy with all the attributes of the default weapon linked to the copy. i guess in this making a copy then paste you won't have to make a copy of every attribute like in duplicate unit.(thought i think if i make change on the copy so it will affect the default weapon, now im trying to make a effect-damage for the copied weapon
I'm not sure what you're talking about here. What you need to understand about duplicating is that it doesn't always reconnect everything as some bits and pieces of abilities and weapons and such aren't attached to them on that list of things to duplicate. It is more effective to either create something from scratch
or duplicate just the main part (i.e. the weapon itself) and then have it link back to everything as it normally would. From there you can duplicate specific things you want to change like the damage effect. Since I assume you don't plan on changing any of the models or actors, you wont need to duplicate and unlink any of that.
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