What causes Prop Pox (and how to avoid it)

[BarbyW]

I have also conducted tests and have the same conclusions as Wouanagaine. In fact I have identified two of the props that Bap identified as specifically causing prop pox. We would be more than happy to have others replicate the testing using Bap's cities as the more independent people confirm the problem the better.

[zilfondel]

I'm going to jump into this thread blindly, just having read the first paragraph and Peg's rebuttal.  I've been playing SC4 for 6 years now, quite the veteran and all, and I have had one very strange experience where the game totally f*cked up one of my cities.

On my other computer, I was running ~1.5 GBs worth of plugins, and one of my small cities in a med-sized region, pop ~15,000, started to have several lots - mostly Marrast's train stations - go black.  All textures and props would disappear, and the lot would cease to function.  I could load the city next to it, and the same lots worked just fine.  Well, I dozed the problematic lots and replopped them, and was fine.  After about a month of playing with this city on and off, saving many times, it came to pass one day that attempting to load that particular city would case a CTD.  Every time, although every other city in the region (using the exact same lots) functioned perfectly.

So, I deleted the city and started over again.  Never had anymore problems...

Not very scientific, but I believe something with the plugins was malfunctioning.

[mightygoose]

well i've played some pretty large cities in the past and never spotted this, but then again it was a long time ago.... warning noted

[dahemac]

A couple of weeks ago I noticed props disappearing from the city in the large center tile of a Paris region I have been working on. I posted a question about it on the BSC Help page and received fast courteous help from some of the great experts here. I was directed to this Prop Pox forum, read it and followed the advice.

I updated BSC MEGA Props Misc Vol02 and removed PEG_TrailParks_305b.dat PEG_TrailPark-Engine_305a.dat and removed a couple of duplicate dependencies from my plugins. I have since built a large city tile to 31Mb with no sign of Prop Pox recurring.

I would like to thank Bap, BarbyW, callagrafx, RippleJet etal. who have done a great job of sorting out this problem so far.

[BarbyW]

I have been doing more testing starting from bap's unpoxed city. I can confirm again once again that on its own the modded beach umbrella from the BDK pack - extracted exactly as it is in the pack - does cause the pox.

[wouanagaine]

here is riquelandia prop pox free that Bap upload, and that I get up to the point of being prop poxed using the involved prop
as you can see in this pict, the prop pox is clearly visible

and here is what is in the savegame ( of course it is a visualisation of what is in the savegame ):


as you can see almost all the middle props have disappears, and all the right props have totally disappeared ( the SC4 shot is from the top right )

This city has been played for only 10 years since I added the involved prop and this is the only custom content used

[BarbyW]

On 3rd March bap posted the following:

As I do have the cdk-www package and it does not cause Prop Pox, I am convinced that the Maxis modded umbrella prop (IID 29000000)  does not cause Prop Pox. I could confirm that by performing another experiment with only that prop exemplar in the plugins folder, but I did not have time yet.

This weakens my original hypothesis that is the increase in size of the modded Maxis props that lead to Prop Pox. The important feature which is exclusive to the other 3 Maxis modded props in the bdk-resource file is being originally a static prop modded into a timed one (this is something no other prop in my plugins folder has). This strengthen the idea that what causes Prop Pox is changing an originally static prop into a timed one without changing its IID. This narrows the search for possible infected props in other prop packs.

This was taken to be a recanting of his theory that a certain group of props caused Prop Pox. Since then a lot of work has been done on investigating and testing. I have previously posted some of my findings but have continued to test and experiment.
I started by taking bap's unpoxed city - Riquelandia 4 - and building the city and savegame file from 119394 population and file size of 15.5MB to 126253 population and a filesize of 25.4MB. I modded two other Maxis props that had a Nighttime State Change to have a Prop Time of Day like the previously identified ones. I made a lot with these - picnic baskets - and played with just that dat and the lot in plugins. After plopping two of the lots, I was able to increase the population to 129173 and a file size of 25.5MB without any sign of PP.

At this stage I removed my modded props dat and after re-entering the city plopped two  more of the picnic basket lots. The props on the picnic basket lots were using both sets of timing information. The original two had the props disappear at 18:00 but the other two had props disappear when night fell.
I was able to increase the size of the population to 131054 with a savegame file size of 25.9MB

I then added a dat with the single modded umbrella from the BDK Resource Pack.
I ran the city to a population of 132021 and then saved and exited. The savegame file was now 15.6MB - the PP had struck.
Here are some images of the city after re-entering:









The only difference between the props that I modded and those that Pegasus modded is that mine are used rarely but his are used a great deal in Maxis low density residential lots.

[QuinRiva]

I too seem to be having this issue and in my case it seems to be particularly bad, losing about 80% of my props.

Farms:

Note that it appears as if a line has been drawn through the rice, wheat, etc fields and props below/right are not drawn.

More farms, again showing a band of props:


Yet more farms:


A military base:


Residential zone:


Etc:


I'm not sure what the file size was before I discovered this problem, but base on how slowly this city runs I would assume it was pretty large.  I've noticed that heavy farming areas take longer to load than other areas, and although this region was about 40%, about 70% of the land was covered in farms.  My plugins folder is about 2.5Gb so the problem could be anything.

Fortunately the region shouldn't be particularly hard to replace.

[allan_kuan1992]

Wow... a total loss...

except you may want to resize your images a bit... they're sticking outside of the forum border.

- Allan Kuan

[QuinRiva]

Yeh, sorry.  They displayed just fine on my screen (my big screen  ), I've shrunk down to 1280 so they should display fine now.

[BarbyW]

Max image size should be 1024 wide, please. Can you have a look at the save game for this city and tell us the size? If you can use Reader, you can also open the save game in that and see the size of the sub file with the Type ID 0x2977aa47.

[wouanagaine]

If it is possible I would like you to upload your savegame somewhere on the net ( yousendit, fileden, etc.. ) and post the url here so we can check stuff inside the savegame
Thanks in advance

[owlsinger]

Wouanagaine: The visualization of the PP pattern in your earlier post on this page exactly matches the pattern in the two cities I had that developed the pox. I did not have the BDK file in my plugins, but I did have the CDK_IND-205.dat and the TrailPark-Engine_305a.dat that BarbyW identified earlier, and I used the TrailParksIII in all my cities.

Kendra

[BarbyW]

I need to go back and test those two files again and also to test out other earlier packs.
I did revert to the unpoxed Riquelandia city and played to over the critical file size with my BSC Props and BSC Textures folders in and it did not corrupt the city. I am trying to cover all bases but it is tedious and lengthy work.

[BarbyW]

I have tested out again with the CDK_IND-205.dat and the TrailPark-Engine_305a.dat in plugins and passed the critical point without any prop pox. I also tested with all the contents of the Legacy CD and that also is clean. Now to work on other files from 2003/2004.

[snorrelli]

I have tested out again with the CDK_IND-205.dat and the TrailPark-Engine_305a.dat in plugins and passed the critical point without any prop pox. I also tested with all the contents of the Legacy CD and that also is clean. Now to work on other files from 2003/2004.

Sorry for being absent from this discussion. I just don't have ANY time lately - even to help research the problem that has troubled me the most over the years of playing SC4. I know there was a question about what plugins I might have had the first time I observed it. The industrial seawalls and the trail parks were my leading suspects... 

[allan_kuan1992]

Well... it may not be just that...

If I read Bap and Barby's minds correctly, the cause might be due to modification to a specific group of original Maxis props without changing the ID.

In that case many more default and custom lots could have used those same modified props. And any of those lots might therefore become a trigger of the pox.

EDIT: Can someone give me the green light on whether the rest of Pegasus' stuff is okay to use? Did bap test the CDK3 port docks?

- Allan Kuan

[BarbyW]

It isn't the lots that are the problem but the props that are used on them. If the props have been modded without changing the IID of the prop then this will affect all uses of the prop in game. The props that we definitely know cause PP are widely used on Maxis low residentials. Thus if a lot of them are present it would seem to result in the PP. We have all been testing in a city that is Maxis only content and reverting to a clean version for each test.
It is never good to mod Maxis props without giving them new IIDs as the modding will affect the instances in a city. We hope to have more of a definite solution with in a couple of weeks but it is a long and boring process. We really would have appreciated some other people doing the tests as the files are available for you to try. That way some other independent results could be shown.

Edit: I haven't tested any of the later stuff as this was first commented on earlier than the release of the BDK. You could always do the tests yourself.

[owlsinger]

I have downloaded Riquelandia, and am playing it with the plugin file I used on my PP'd cities. I have also enlisted a special group of workers in the northwest corner for a special project! 



I will keep track of my results and let you know.

Kendra

[BarbyW]

Funnily enough I haven't seen the crowd trying to escape the pox but then I never cleared a small area of land for them.
I hope you have just the prop/resource/textures in place and not the lots - especially the growables as that could make a difference to the the final result. I also see that you have plopped the Census Repository. The testing so far has only been done with Maxis content in the city and the assorted prop/resource/texture packs.
Thank you for testing this out, Kendra. Another voice will be appreciated. Once you have your results maybe you could test out from the base city again but with just the BDK Resource pack - just to corroborate the findings already shown.