Using ZScript for Collision Blocking: How?

[Rex Claussen]

@ Ed the Bat, in this post you said:

At one point, I redid how these large vehicles handle their collision boxes; instead of having to place the invisible 'blocking' actors around them on the map, the vehicle actor does it automatically via ZScript.

Would you please explain, in layman's terms, how you accomplished this? I would like to use ZScript for collision blocking of models in Zero Dark: Theta.

Thanks.

[Ed the Bat]

I'll use the bulldozer as my example. Before I joined the project, it was originally done thusly:

Screenshot 2025-03-10 151553.png (399.92 KiB) Viewed 24379 times

A number of Custom Invisible Bridge actors of various heights and radii arranged carefully around the actual bulldozer actor. Naturally, this struck me as something tedious to recreate in the event, say if a mapper wanted to place another bulldozer. One would have to copy/paste this whole setup, or recreate it from scratch. Especially tedious if changing the orientation. Plus it just looks messy in the map editor.

So, I opted to create some actors in ZScript that replicate the function of those Custom Invisible Bridge actors. Here are the ones for the bulldozer (as well as one from the robotic loader since I inherited from it as a base class)

Code: Select all

class LoaderBox : Actor
{
	Default
	{
		Radius 32;
		Height 64;
		+SOLID
		+NOGRAVITY
		+NOLIFTDROP
		+ACTLIKEBRIDGE
	}
}

class BulldozerRoof : LoaderBox
{
	Default
	{
		Radius 36;
		Height 2;
	}
}
class BulldozerFront : LoaderBox
{
	Default
	{
		Radius 16;
		Height 40;
	}
}
class BulldozerSide : LoaderBox
{
	Default
	{
		Radius 16;
		Height 24;
	}
}
class BulldozerRear : LoaderBox
{
	Default
	{
		Radius 8;
		Height 64;
	}
}
class BulldozerPillar : LoaderBox
{
	Default
	{
		Radius 2;
		Height 64;
	}
}

Now that I've defined my analogues of the Custom Invisible Bridges, I tell the bulldozer in ZScript to spawn and position these invisible blocks automatically upon its genesis by using the PostBeginPlay() function.

Code: Select all

class Bulldozer1 : ModelBase
{
	override void postbeginplay()
	{
		A_SpawnItemEx("BulldozerRoof",-8,0,88);
		A_SpawnItemEx("BulldozerFront",80,-32);
		A_SpawnItemEx("BulldozerFront",80,-16);
		A_SpawnItemEx("BulldozerFront",80,16);
		A_SpawnItemEx("BulldozerFront",80,32);
		A_SpawnItemEx("BulldozerFront",48,-16);
		A_SpawnItemEx("BulldozerFront",48,16);
		A_SpawnItemEx("BulldozerFront",-48,-16);
		A_SpawnItemEx("BulldozerFront",-48,16);
		A_SpawnItemEx("BulldozerSide",-48,-32);
		A_SpawnItemEx("BulldozerSide",-16,-32);
		A_SpawnItemEx("BulldozerSide",16,-32);
		A_SpawnItemEx("BulldozerSide",48,-32);
		A_SpawnItemEx("BulldozerSide",-48,32);
		A_SpawnItemEx("BulldozerSide",-16,32);
		A_SpawnItemEx("BulldozerSide",16,32);
		A_SpawnItemEx("BulldozerSide",48,32);
		A_SpawnItemEx("BulldozerRear",-32,0);
		A_SpawnItemEx("BulldozerPillar",-48,-32);
		A_SpawnItemEx("BulldozerPillar",-48,32);
		super.postbeginplay();
	}
	Default
		{Height 36;}
}

Now that the bulldozer makes them automatically, mappers don't need to place them. Simply placing the bulldozer itself in a map will be enough.

[Rex Claussen]

I understand the general principle, but I'm afraid it's beyond my coding ability, unless I start with your code and customize for a new actor.

But more fundamental than the coding is this question: How do you determine the height, radius, and position of each invisible bridge thing surrogate? Did you get those from the actual invisible bridge things I had used?

This is important to me, because if you used the attributes of the invisible bridge things, I would need to go through that exercise to create blocking for the Zero Dark: Theta models. I don't look forward to that.

[Ed the Bat]

How do you determine the height, radius, and position of each invisible bridge thing surrogate? Did you get those from the actual invisible bridge things I had used?

Yes, I was simply re-producing what you had done originally. Matched their height/radius values, and did some basic math with their coordinates to see how far offset they would need to be from the main actor. In short, I'm afraid I do not know of a faster or smarter way to generate them. I have this vague feeling that I've seen discussions elsewhere that it can be done, but it would require tools and know-how that I simply don't have.

[Rex Claussen]

Thank you, Ed. I was afraid that I would get the answer you gave. Ah, well!

On a related topic, I vaguely remember requests for a vertex blocking feature, but I don't imagine anything came of it.