[H E L P] Retrieving a thing's sector tag

[Jimmy]

Surely. Surely there's a way to retrieve the tag of the sector a certain thing is standing in. But either I've forgotten or it hasn't existed all along.

[RaveYard]

I am sure there isn't such feature.

But you can substitute with a very ugly hack...

---

Code: Select all

// Conditions you must meet for this function to work 100% properly
//
// TID is not 0
// TID is used only by one actor
// The sector's tag must be between 1 and MAX_SECTOR_TAG. If not in said range, then the function will return 0.
// Watch out for runaway termination.

#define MAX_SECTOR_TAG 9999
function int Thing_GetSectorTag(int tid)
{
	for(int i = 1; i <= MAX_SECTOR_TAG; i++)
	{
		if(ThingCountSector(0, tid, i))
		{	
			return i;
		}
	}
	return 0;
}

Or you can just rethink what you are trying to do and try to think of an another way to do it.

If you work with a grid pattern of equally sized sectors, then the solution is using your actor's X Y position.

[Jimmy]

That's helpful though, thank you! Honestly ugly hacks are pretty much all I'm doing at this point.

Though I'm a bit concerned about runaway. How likely is this to happen? I realise doing 10,000 checks in one tic is already pushing it...

[KeksDose]

There is no danger of runaway here, as far as I know. The instruction limit lies at 500,000 per tic. If this is inside of your own maps, you can do the fairly trivial optimisation of setting MAX_SECTOR_TAG to the highest sector tag in your map. If they are not inductive, use an array and cycle through that. You can use acsprofile in the console to see if the trade-off is worthwhile!

I think ThingCount can also use const in the first argument to reduce instructions being pushed (I am unaware of the details here, but if you do not use expressions, you may use const to lower the probability of runaway happening). May be worth trying for ThingCount_Sector, if it does work for that function.

[RaveYard]

That's helpful though, thank you! Honestly ugly hacks are pretty much all I'm doing at this point.

I wouldn't worry too much about it. You probably will not end up needing to write custom collision and hitscan detection in ACS...

There is no danger of runaway here, as far as I know. The instruction limit lies at 500,000 per tic.

True, but even without getting terminated, it can still cause frame-rate drops.

I think ThingCount can also use const in the first argument to reduce instructions being pushed (I am unaware of the details here, but if you do not use expressions, you may use const to lower the probability of runaway happening). May be worth trying for ThingCount_Sector, if it does work for that function.

As my knowledge goes, you can use const, only when all arguments are constants

[Nevander]

I always wonder why it can't be as simple as a function to do exactly this, something like "checkThingSector(TID)" and you put in the TID and the function returns the sector number.

[NeuralStunner]

I'm pretty sure it would be possible, but nobody's done it yet.

[cocka]

Yes, the main problem here is that you cannot retrieve the sector tags at all, so the only option to circumvent the problem is to use the previously written for loop to test whether the thing with an actual tid exists in a sector with given tag or not.

[Graf Zahl]

Besides, what should it return for sectors with multiple tags?

Threads like this exist because people try to use some information for doing stuff it was never meant for.
And instead of asking how to do what they really intend to do, they ask how they can implement it in the broken way they cooked up.

(In clear English: What is missing here is, why the hell do you need this information to begin with?)

[cocka]

sectors with multiple tags

Have I missed something here? I don't know anything about sectors with multiple tags.

[Graf Zahl]

Yes, you have missed something there. That feature has been available for more than a year.

[cocka]

And is there a wiki article or a description about it?

[Accensus]

http://zdoom.org/wiki/tag

ZDoom, using UDMF maps, have the ability to read in multiple tags per line or sector. Doom and Hexen map types will not work with this, however, and neither can things.

[Jimmy]

Besides, what should it return for sectors with multiple tags?

Threads like this exist because people try to use some information for doing stuff it was never meant for.
And instead of asking how to do what they really intend to do, they ask how they can implement it in the broken way they cooked up.

(In clear English: What is missing here is, why the hell do you need this information to begin with?)

I apologise for astounding you with my idiocy. Geez.

Say you want to quickly place things in a bunch of sectors, and affect only the sectors those things are placed in. Like have a torch that sets the sector color to red, for a crude example. You probably don't want to hear what I was originally planning on doing, it'd take way too long to explain and I quickly found it wasn't going to work out anyway. My initial query was just vague because I wasn't aware that there was apparently a lack of connectivity between thing and sector, and wanted confirmation on that. It sounds like the sort of thing that should be possible, is all.

Maybe something like ActivatorSector() would be more useful. Like ActivatorTID(), except it would only return the singular sector the actor is currently in. Sector tags needn't be involved. I'm not familiar with ZDoom's internals on any conceivable level but if the sector number a thing is currently in could be exposed to ACS, then this, I imagine, would be handy to have as a quick void function.

[Graf Zahl]

Since ACS has no access to single entities like that it simply cannot be done. This is very deep in WFDS territory.