What causes Prop Pox (and how to avoid it)

[tito_golden]

Hello everybody every of you masters of developing fun...

my pox case have began yesterday... no images needed isnt it??

after reading about a lot today (what a headache), i think i can resume my case in this...

POXED CITY:

Name Terraxons(2):

weight of SC4 file: 16,8 and goes to 16,6 after working a lot in it (seems to have the symtoms...)

weight of network subfile (2977aa47): 4,85 mb (<6mb limit bap has reported on page 1!!!)

analysis with savegame explorer: positive in pox:

Report:

Prop poxed city !!!
Buffer corruption occurs around offset 0x00DCA95F
163248 props found in city
Some infos about the props:
-11488 disabled props found in city
-2264 tracking props found in city
-3118 timed over year props found in city
-14583 dayly timed props found in city
-17634 conditional props found in city
-From what kind of data :
--41 props alone
--138276 props from lot
--13437 props from T21

In the map that shows... the grid appears with not the complete extension... in the four edges! but pox occurs also inside the correctly showed grid

NO POXED CITY:

Terraxons:

weight: 26 mb and not less

weight of network subfile (2977aa47): 17,9 mb

analysis with savegame explorer: negative in pox:

I have beaches, but i think i have no PEG beach pack (i´ve searched for the infamous file in my plugins folder with no results... any hidden location i should know?)

Recent upgrades:

I´ve installed several plugins and upgrades... one of them, the great RTMT upgrade (RTMTv3.60)

I´ve follow the instructions the best i can, my english is not the better, and make some mess with the instructions...

but for what i´m reading here, bus stops could be a problem, so i´ve decided to report my case.

it is not the same as dahemac cause i´ve been alerted by savegame explorer as prop disabled!!

i´m going to try to test what happens if in the non poxed city i´ve also reported, i do the following:


- run it now (i´ve not opened since the last upgrade but, the SC4 file is changed in 200 kb)

- then save

- then re-enter and pray and see if pox has arrived to the city

- if not, or if yes, test it with savegame explorer.

- Then i will change the actual one, for the backup just before doing the upgrade

- run it with the upgrade and repeat...

- if pox dont appear in any case, should be related to new plugins installed

- as i´m reading about RTMT, im going to bulldoze the new bus stops i´ve put in the poxed city

- then delete RTMT files and better put the older ones and try to open the poxed city

- lets see what happens (maybe the city is not poxed anymore?, maybe still poxed even without new RTMT, i remember to read someone says that once poxed... impossible to recover)

What do u think could happen???

Any further step you, seniors, recommend me to do, to do instead of one i´ve mentioned, or to include in some position???

If nothing good occurs, i´m going to try to go back to the last backup, and reinstall all the stuff i´ve recently upgraded, all but not RTMT and lets see... notice that my network subfile in poxed city is under 6 mbs and the one from non poxed, over 17...

one more... should the skipping 1 to 6 z´s method steps solve my problem even with RTMT3.60 as now?? this is forever? have to repeat sometimes when pox attacks? how it works in this way??

i remember, my understanding of 26 post pages of english is limitated, be good with me

At last, thank u very very much for all the tests, the plugs, the props, the... all in SC4devotion... you´re crazy, men!!!

[sneekypetepuma]

I had been playing with an old city of mine... and noticed that there were many missing props... I chanced upon this forum and did a little investigating myself... when I opened the city Greenville.sc4 .. i looked at section 2977aa47 and noticed that its a LOT larger than any of the files that others were finding... mine is 75,617,388. what the heck does that mean !!!!!!

[tito_golden]

since í´ve written my post reply some weeks ago, i´ve decided to investigate myself and i´ve done an exhaustive test to my poxed city.

(the test is reported in a Word document, to be able to go back and see the steps i´ve follow to get some solutions, which is able to anybody to see it if wants, only have to ask for it)

I have no time since august to play nothing, so i´ve not been able to continue with the test, even not able to write here... but i´m completely at your disposal if someone wants the city, its bacukps and the document to see and test somemore.

in some case of study... i´ve been able to avoid pox in a 99% of its effects, still there... but are good news.

The backup i have of the poxed city (only few weeks ago the pox strikes for the first time) show (with SC4save) no sign of pox in the results. But have 5 disabled props.

With the map that SC4save is able to show, with the localisation of all props, i´ve been able to see where the disabled props are exactly (appearing in glowing white) in the backup version with the "Prop pox free city" message.

These props all correspond to "April´s seafood shack" location. ("Newman Inc Wooden Waterfront Commercial" if i remember good)

I´m not saying that this Newman creation causes pox, i say that my disabled props are in that location (the five)

I´m not going to be able to see if in this location, some years ago, were other stuff, at least now, i´m going to see if i have more backups, but i think no other stuff never there...

Do you think, is something to do with the backup, to recover the missed props in the not poxed city, to avoid pox striking? someone has proof reinstalling stuff in a similar case???

THANKS A LOT FOR YOUR ANSWERS!!!! (and like always, sorry if my english is not the best...)

Related to "sneekypetepuma" as i know, 2977aa47 over 16 mbs let pox to strike but, have you tested the city with SC4save? get the pox free or poxed city message?

i have other cities with elevated weights of 2977aa47 files and no pox, cause no missed props. As I know, once poxed, impossible to recover (i´m lucky to have a not poxed backup, you?)

kind regards.

[Wiimeiser]

Question: Will obliterating or deleting an affected city fix Prop Pox?

[bap]

Question: Will obliterating or deleting an affected city fix Prop Pox?

Hi Wiimeiser. Yes, obliterating or deleting the affected city will fix its Prop Pox occurrence. But this means you loose all development you have done in that city. Before starting to build it again, be sure to check if you have the PEG BDK resource file in your plugins (and if you find it, you may either remove that package or modify it according to one of my earliest posts in this thread in order for it to become harmless). It is also advisable to read the last 4-6 pages of this thread to be aware of more recent possible causes of Prop Pox. Good luck!

[teddyrised]

It's statistically difficult to prove this point, but I realize that when I blocked the growth of Maxis residential lots (all wealth), the prop pox does not surface. I used to play a region with the aforementioned problematic plugin, and only the first largest tile city was affected - and that city was constructed prior to blocking off Maxis building growth. And since it is known that the problematic timed prop appears on Maxis residential lots, the region I played provides (somewhat) circumstantial evidence that as long as Maxis residential lots don't grow, the prop pox does not manifest itself (since the props will not appear in the city tile whatsoever).

[z]

Most people never get the prop pox - it's quite rare - so I think the sample of a single player here is really not enough to show anything in these circumstances.

[noahclem]

For purposes of Prop Pox and the network subfile, do MMPs count as props or something else? I don't have any experience with the Pox but that could be because I've never had a city's network subfile go over the critical size. All of my cities so far were begun with the known problem file PEG CDK resource installed, though I don't know that those props ever appeared on a lot in Siilijoki (no CDK lots in my towns though it's possible a different plugin used that dependency). Does that mean that my cities are potentially "ticking time bombs", susceptible to the Pox if they reach a certain size? As an adaption to my last computer's slow speed all my cities have significant areas covered by water where lots will never be placed (large tiles still played excruciatingly slow) so hopefully I never reach the critical network subfile size.

Thanks in advance for clarifying the issue here 

[vortext]

For purposes of Prop Pox and the network subfile, do MMPs count as props or something else?

Technically MMPs are counted as flora and as far as I know flora isn't stored in the network subfile.

All of my cities so far were begun with the known problem file PEG CDK resource installed, though I don't know that those props ever appeared on a lot in Siilijoki (no CDK lots in my towns though it's possible a different plugin used that dependency). Does that mean that my cities are potentially "ticking time bombs", susceptible to the Pox if they reach a certain size?

Since the issue is improperly modded Maxis props, it's certainly possible other lots use a poxed prop - so to speak - so yes, your cities could become affected if the network subfile grows large enough. You could depox the CDK file fairly simple though, just delete the simulator properties from the exampler files. Or delete the exampler files alltogther since they're Maxis props to begin with, so there won't be any brown boxes or anything.

[Swordmaster]

Doesn't SC4Save tell you if your city is poxed at any time? Or only when you go over the file size?

Cheers
Willy

[jdenm8]

Only after you've gone over the filesize and the game has corrupted the network subfile.

[Swordmaster]

Well, Noah, then you could always run a test on your cities: turn the water into land, and build something prop-heavy on it (like seasonal forest lots or something) to push it over the size. Then see if it's poxed.

Cheers
Willy

[asser]

I've just spent two days reading this thread (and gosh there is a lot of great info in here  )

I have the BDK file and I have the RTMT and SG bus stops, so what is my course of action?
I would very much like to use both of these in the game (without the pox issue) if this is possible.

Sorry, but my head is spinning with all this info so I'm not entirely sure what to do now. I think for the BDK i'll have to go for either the 2nd or 3rd option, but what about the busses, were those confirmed as a prop pox cause? I have the 3.6 RTMT installed.

Edit: Oh and forgot to mention that I have the pox at the moment in several cities, so the "don't worry if you build small cities" part doesn't apply to me in some cases

[z]

I have the RTMT and SG bus stops, so what is my course of action?
I would very much like to use both of these in the game (without the pox issue) if this is possible.

Sorry, but my head is spinning with all this info so I'm not entirely sure what to do now. I think for the BDK i'll have to go for either the 2nd or 3rd option, but what about the busses, were those confirmed as a prop pox cause? I have the 3.6 RTMT installed.

As far as RTMT goes, as long as you follow the installation directions, you should definitely have no problems with the prop pox.  And if you follow the instructions properly, you can use RTMT with SG's bus shelters along with SG's standalone bus stops with no problems.  Many people do.

[asser]

Great news on the RTMT/SG

I'm trying to replace the props on the lots, but when I try to save I get the error saying "lots must have a base texture for each lot" I should have all dependencies installed. Is there some trick I'm missing?

The lot looks like this in LE


As far as I recall there shouldn't be a texture for the sand?

[Swordmaster]

Every tile in LE needs a base texture, yes. You can remove it afterwards in Reader. Open your LOT file, and find the LotConfigPropertyLotObject line starting with 0x00000002 and ending with the texture's IID. Delete that line, right-click and Reindex Lotconfig. Done.

Cheers
Willy

[z]

I have a question for the Prop Pox experts.  It's quite clear that replacing an untimed prop with a timed version of the same prop using the same TGI can trigger the Prop Pox.  I'm currently working with a situation where a Maxis timed prop is overwritten by a timed prop with the same TGI.  However, the newer prop is larger, because it has a second RKT4 - in this case an RKT4 xm, which allows the prop to be mirrored.  So there's a second timed RKT4 in the second prop.  Is this a possible cause of the Prop Pox?  This prop has been around for years, apparently with no problems, but instances of something that at least resembles the Prop Pox (and may very well be the Prop Pox) have arisen recently.

[vortext]

While I'm no expert on the subject I'd reckon it could be reason for concern indeed. As I understand it the pox is caused when there're two exemplars with the same TGI which differ in size, i.e. the amount of information each hold.

Now, when SC4 game reads its vanilla files, it sets a buffer of Ni bytes to store the info of prop i in memory. When it later reads again the info of that prop in the custom prop file it find 73 extra bytes of information to store and it keeps writing beyond the expected final memory position of that prop. Thus, it overwrites other things and messes up the program buffer. This is memory overflow, an easy way of loosing track of how many props you have installed and where in memory the corresponding info starts/ends.

The 73 bytes mentioned pertains to the specific example bap gives but it's easy to see how the same memory overflow applies in this case. To see if a city is affected, check the size of the network subfile.

[Kergelen]

I got Prop Pox in my main city. Fortunately, thanks to the information contained here and following  z's steps, the Prop Pox is solved.
There is only one thing I could not fix: the MMP that I put over some Lots disappear once I have solved the PropPox. When the city got Prop Pox the MMP over the Lots remains, but when Prop Pox is solved the MMP disappear  .
So now I got MMP_over_Lot Pox 

Someone has any idea how to keep MMP on the Lots? There is a file that contains MMP information in the city file? If so, I could copy the file from the poxed city file to the healthy city  file...

PD: No problem with the MMP over the "normal" terrain.

[cogeo]

According to our hypothesis about the prop pox, the problem isn't related to the exemplar or its size (ie the "definition" of a prop), instead it is related to the different (wrong) size of the prop instance (or "reference", if you prefer) in the savegame. It's not the exemplar itself that is saved in the savegame, but instead a much stripped-down reference, which contains information like the IID, along with the "positioning" stuff, like coordinates, orientation etc (these are not contained into the exemplar of course). Everything else (model's TGI, name, LTEXT, behaviour on slopes etc) are properties that are read from the exemplar (and that's why we can change a prop's model, for example, without problems). Timed props are different, in that they need to store additional information in the savegame, like state, days since last activation etc, resulting in a different length of the record to be written in the savegame. It seems that the game doesn't check the length of the record saved in the savegame (it may actually not even precede the record with a "length" field - to save space), instead it seems to determine the record size by checking the prop exemplar (a timed prop creates a longer "prop reference record"), so if the prop reference was created with a different timed/untimed definition (and then this definition is changed by installing/uninstalling a plugin that overrides the prop, redifining it from simple to timed or vice versa), the program is "lost", and the prop pox occurs.

So the answer to your question is find the record lengths of the two props. The exemplar size makes no difference, the key is the size of the prop reference records generated in each case. If the record lenghts are equal, there will be no pox, although the prop's activation state may be wrong when it is first loaded (and it will remain wrong until reset, eg in a game-year).

Please note that a prop that contains a RKT4 property isn't necessarily timed. The RKT4 may simply display multiple models (through a single exemplar), or just shift a model's position, or even display different models during the day and nighttime (using the NightTimeChange property). Such a prop is NOT timed and no additional information is saved in the savegame, as the game does not need to keep track of it; it just displays different models during the day and the night. As for the RKT4xm, I have only seen this property (defining additional, "mirrored" models) in network props, where a network tile may be defined as a mirrored version of another one. I believe such props aren't "timed" either.