Message system discussion

[Gleeok]

Callbacks are in for stateful scripts (ie.; scripts with persistent stack space). For global callbacks these should be declared global procedures by scripts. I can add any procedure to call these on the script side easily, just need to spec the desired arguments and return values and then add them to ZC first.

There's a slight annoyance with classes though: Script classes cannot inherit from application classes, so for example a scripted npc with an npc property can't do 'this.X = 0', but instead '(this.)npc.X = 0', which is weird. This requires an extra layer of a scripted base class to define these properties and get them from the engine... I *think*. The problem is we are short of people, especially with Saffith leaving. I wouldn't be surprised if npcs have to wait one version... :/ Unlimited screen scripts, map scripts, global scripts, and various callbacks might be enough for an initial release, which isn't so bad I guess.

One nice thing is the memory usage isn't too bad. Compiling and updating 2048 global scripts -each script uses only a few kb.

[Saffith]

There's a slight annoyance with classes though: Script classes cannot inherit from application classes, so for example a scripted npc with an npc property can't do 'this.X = 0', but instead '(this.)npc.X = 0', which is weird.

You can use virtual properties to work around that.

fix X
{
    get const { return npc.X; }
    set { npc.X=value; }
}

That also has the advantage that the handle can be made private in the base class, so you can't accidentally point it to another enemy.
One minor issue what that is that you can't use increment and decrement operators on virtual properties. I think it should be possible to add them, though, if you don't mind messing around with AS's code a bit. They were deliberately removed, and I forget the reason, but I think it had to do with multithreading issues that aren't relevant to ZC.