How to deal with weapon action function in scripting

[Graf Zahl]

Haven't you read this thread? It was all about dealing with the bad access. Of course you have to add null pointer checks.

[Major Cooke]

Yes, I did. I meant crash prevention itself.

[Graf Zahl]

The best you can get is a message 'null pointer access in function 'blahblah' and have the game terminate. It should be clear that this will put a lot more responsibility in the hands of modders.

[Major Cooke]

Ah, so we would do

Code: Select all

if (target != null && target.num != null)

to ensure they have the variable?

[Graf Zahl]

If you do not have num it'd give you an error at compile time. This is not Javascript where you can attach any arbitrary new variable to an object.
You also need to cast 'target' to the proper type first if you want to access information from a child-class. It also means that, if you want to give a new property to multiple classes, they need to have the same base class where you define that new property.

[Major Cooke]

So something like this, for target casting type?

Code: Select all

class MCD : Actor 
{
	Default
	{
		int whatever = 2;
	}
}

class Checker : Actor // Should this be inheriting from MCD?
{
	States
	{
	Spawn:
		TNT1 A 0 NoDelay
		{
			if (CheckClass("MCD",AAPTR_TARGET))
			{
				MCD SpecialTarget = target;
				if (SpecialTarget)
				{
					bool check = (SpecialTarget.whatever > 0) ? true : false;
				}
			}
		}
		Stop
	}
}

[Graf Zahl]

More like this:

Code: Select all

class Checker : Actor // Should this be inheriting from MCD?
{
   States
   {
   Spawn:
      TNT1 A 0 NoDelay
      {
            MCD SpecialTarget = MCD(target);
            if (SpecialTarget)
            {
               bool check = (SpecialTarget.whatever > 0);
            }
      }
      Stop
   }
}

[FishyClockwork]

Okay, so something like this will work?

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//Instead of calling GetWeapon() from ACS
if( Actor(target.player.ReadyWeapon).CheckClass("BFG9000") ) //assuming nothing is NULL
{
   //stuff
}

[Major Cooke]

See here.

[Graf Zahl]

Okay, so something like this will work?

Code: Select all

//Instead of calling GetWeapon() from ACS
if( Actor(target.player.ReadyWeapon).CheckClass("BFG9000") ) //assuming nothing is NULL
{
   //stuff
}

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if( BFG9000(target.player.ReadyWeapon)) //assuming nothing is NULL
{
   //stuff
}

No need to cast to intermediate types.

[FishyClockwork]

I had a feeling I could do that.

So how do I get an actor's classname and store that in a variable to compare it with other things?
In particular, say I have two actors: target and tracer. I don't know what classess they are and I don't care.
What I do care is if the two actors are the same class but not the same entity. How do I do that?

[Graf Zahl]

That's not defined yet.
I guess something like 'typeof(object)', but don't nail me on it.

[Xaser]

Seems like the decision is pretty much a done deal, but +1 from me anyway on Graf's goal to keep self as the player and have invoker be the weapon. This matches what DECORATE modders expect, plus we finally get to access those pesky weapon vars through invoker.

[FishyClockwork]

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if( BFG9000(target.player.ReadyWeapon))

This got me wondering, is load order going to be an issue?

IE is this gonna get me an error?

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//'A' references 'B' even though 'A' is defined before 'B'
class A : Actor
{
    B other;
    States
    {
        ...
        ...
        BLEH A 2 { other = B(tracer); };
        ...
        ...

    }
}
class B : Actor
{
     //stuff
}

[Major Cooke]

And at long last overlays can have their own variables to initialize and use.

Oh man. Other actors having overlays is going to be fun. I suspect with zscript they'll currently be able to perform multiple states similar to how overlays work, only they don't draw images... yet.