How Proximity Effects Work?

[Eusebio Ptolomeu 24]

When I analyze the game with iLive Reader, I notice some interesting varibales within the developmento of residential simulator, at General -> Developer -> Residential $/$$/$$$. There, we can find elements called "Proximity Effect", and they seem to dictate how the proximity to a certain type of development impacts the desirability for other developments. For example, it looks like being next to R$ sims is undesirable for R$$$ sims. But I would like to know a little more about how this effect work.
1- First, how should the sequence of numbers be read? Is it an alternation between a given distance X and the development impact for being X tiles aways from the building?
2- Also, I would like to have a sense of scale: I see that the development impact in being next to R$ for R$$$ sims are around values such as -5, -3, etc. How big is this -5 impact in the overall desirability calculation? Can it make a big difference? Or is it too low a number, compared with other impacts such as education and garbage, to matter in the game? If too low, I would like to increase it to see if we can have more gradual separation between different wealth levels (it's so easy for me to have wealthy mansions next to poor homes, I think we should have some R$$ gradient between these two).

[CorinaMarie 29,605]

2 hours ago, Eusebio Ptolomeu said:

1- First, how should the sequence of numbers be read? Is it an alternation between a given distance X and the development impact for being X tiles aways from the building?

Yes, that is correct. They are in pairs. 

When I'm dealing with those type of properties, I like to copy the whole shebang from the "Values as text" area at the bottom, paste them in N++, and then using my Enter key separate them on to separate lines, and add spaces as needed to line them up.

Here's the Proximity Effect: R$ from the Residential R$$$ Developer when done that way:

  0.000000,-5.000000,
 15.000000,-5.000000,
 30.000000,-5.000000,
 45.000000,-5.000000,
 60.000000,-5.000000,
 75.000000,-5.000000,
 90.000000,-4.000000,
105.000000,-4.000000,
120.000000,-4.000000,
135.000000,-4.000000,
150.000000,-3.000000,
165.000000,-3.000000,
180.000000,-3.000000,
195.000000,-2.000000,
210.000000,-2.000000,
225.000000,-1.000000,
240.000000,-1.000000,
255.000000, 0.000000

(This technique is really handy when tweaking colour ramps for data views too. )

Anyhow, it seems likely they were originally higher and distinct values in the 2nd column in early testing and then they backed off. The way these sorts of ramps work they could do the exact same thing with:

  0.000000,-5.000000,
 75.000000,-5.000000,
 90.000000,-4.000000,
135.000000,-4.000000,
150.000000,-3.000000,
180.000000,-3.000000,
195.000000,-2.000000,
210.000000,-2.000000,
225.000000,-1.000000,
240.000000,-1.000000,
255.000000, 0.000000

Because in both sets any distance from 0 to 75 cells will have a -5 influence. Those in the range of 76 to 89 will be interpolated between -5 and -4. (And so on.) I suspect they left them with all the distinct cell distances for conformity with other similar properties.

 

2 hours ago, Eusebio Ptolomeu said:

How big is this -5 impact in the overall desirability calculation? Can it make a big difference?

I believe it's quite minor compared to what the super over powered park and landmark lots can do. I really suspect in the earlier tests those were toned down a bunch, but during play testing the average person struggled so they bumped the park and landmark effects up to ridiculous values.

 

2 hours ago, Eusebio Ptolomeu said:

If too low, I would like to increase it to see if we can have more gradual separation between different wealth levels

Trial and error will work wonders here. If I were testing them, I'd multiply the 2nd column by 100 for an initial test. And then I'd guess it would be damn near impossible to grow R$ and R$$$ side by side without a ton of other influences.

Ofc, I'm not suggesting 100x is a viable number, but it's a starting point to make certain we can actually see this is doing something. Next I'd drop to 10x and see how that goes. Then, depending on what you find out, tweak up or down from any which one. Or a more stair step set of values. Maybe go 500 for up to 10 tiles then 250 for the next 10, 125 for, say, another 5, and ween them off to zero by 40 tiles distant?

Also, you can use the advanced hover over for more info per lot and/or create the Query.txt to compare desirability between versions of your tweaks to the Developer Exemplar.

Good luck. I look forward to your findings.

[Null 45 3,041]

24 minutes ago, CorinaMarie said:

When I'm dealing with those type of properties, I like to copy the whole shebang from the "Values as text" area at the bottom, paste them in N++, and then using my Enter key separate them on to separate lines, and add spaces as needed to line them up.

That is probably the easiest way to do it, Ingred.ini says that those properties are a GeneralResponseCurve. 

The Maxoids had a special editor for that data, but I have no idea how it was supposed to be launched or even if it would still work in the shipping game. Based on the Mac binaries the editor appears to have been able to render the text values as an actual curve.

[Eusebio Ptolomeu 24]

I will set up some experiments here, see how they go.
In general, do we know what is the value range for desirabilty in this game? Knowing the max/min values, it could be easier to predict a good weight for this Proximity Functions. For example, what is the maximum value of desirability the game considers? 100, 255? Maybe on the 1000s?
Also, just one more question: the distance values, do they represent number of tiles? For example, in the pair  (255.000000, 0.000000), does it mean 255 city tiles, or is there some conversion? Considering the largest map has a lenght of 256 tiles, I think it could be as direct as representing game tiles indeed

[CorinaMarie 29,605]

15 minutes ago, Eusebio Ptolomeu said:

In general, do we know what is the value range for desirability in this game?

I sort of think I used to know, but I'll leave this for Null as he'll have direct access to the exact info.

 

16 minutes ago, Eusebio Ptolomeu said:

Considering the largest map has a length of 256 tiles, I think it could be as direct as representing game tiles indeed

Yes, I'm certain it is in number of cells away. 

For the top distance, 255 would be the furthest one could get from a corner cell. For the zero for the lower distance, they are just taking the liberty of not saying one cell away because it gets worked into a range of zero to something (and in the quoted case: 75).

New idea: I have been wondering if even testing -1000 might not make much difference since there are 10 or 12 (or some number) of things which all affect desirability. It might be even if this particular proximity effect is huge, it might still then only become 8 or 10% of the whole calculation.

[Eusebio Ptolomeu 24]

6 minutes ago, CorinaMarie said:

New idea: I have been wondering if even testing -1000 might not make much difference since there are 10 or 12 (or some number) of things which all affect desirability. It might be even if this particular proximity effect is huge, it might still then only become 8 or 10% of the whole calculation.

It's possible, but I was just taking a look at other desirability effects, and I think values around 10s are on the right ballpark. For example, apparently the "School Effect" for R$$$ is only -25 when the school value is 0; and I would suggest that no schooling for R$$$ should be one of the main desirability killers in this game. Radiation effect seems to be a whopping -2000, but radiation was always a game over when it comes to these things, now I guess we know why. Values around the 10 to 20 range seems to be the norm for individual influences; I will just try to double the values for the original Proximity Effect and see if I notice any difference.

[Null 45 3,041]

2 hours ago, CorinaMarie said:

I sort of think I used to know, but I'll leave this for Null as he'll have direct access to the exact info.

It appears to be a Sint16, so the range would be [-32768, 32767].

[Eusebio Ptolomeu 24]

Ok, I admit that testing it could take a little more time. I use CAM, and as such, this inteferes with the dynamic of the Big City Tutorial, which would be the place I would use to quickly test the effects. I will se what I can do; but if anyone with a better knoweldge about the game is interesting in test the modifications, I'm attaching the dat file here (remember, this is a modification of the CAM mod, so keep its effects in mind).

I actually tried 2 modifications, one being the Proximity Effect (in which I basically tripled the negative effects between R$ and R$$$; medium-wealth is neutral for everybody) and some modifications involving caps such as "Water Cap", "Fire Protection Cap" and "Park Cap". This second one is kind of simple, basically speaking, no R$$ excuses no water anymore, and R$$$ further demands to be protected from fire (to be inside the coverage of a fire station).

For clarity, the only modifications I made here are in the "Proximity Effect", "Water Supply Cap", "Fire Coverage Cap" and "Park Cap" functions and for the Residentials only, everything else is untouched.

CAM_2.1.0_PlayStyle_Extended_Modded.dat

[Ulisse Wolf 4,412]

27 minutes ago, Eusebio Ptolomeu said:

Ok, I admit that testing it could take a little more time. I use CAM, and as such, this inteferes with the dynamic of the Big City Tutorial, which would be the place I would use to quickly test the effects. I will se what I can do; but if anyone with a better knoweldge about the game is interesting in test the modifications, I'm attaching the dat file here (remember, this is a modification of the CAM mod, so keep its effects in mind).

I actually tried 2 modifications, one being the Proximity Effect (in which I basically tripled the negative effects between R$ and R$$$; medium-wealth is neutral for everybody) and some modifications involving caps such as "Water Cap", "Fire Protection Cap" and "Park Cap". This second one is kind of simple, basically speaking, no R$$ excuses no water anymore, and R$$$ further demands to be protected from fire (to be inside the coverage of a fire station).

For clarity, the only modifications I made here are in the "Proximity Effect", "Water Supply Cap", "Fire Coverage Cap" and "Park Cap" functions and for the Residentials only, everything else is untouched.

CAM_2.1.0_PlayStyle_Extended_Modded.dat

Just a warning

CAM 2.1.1 is no longer supported. You should use CAM 2.5 for experiments

[Eusebio Ptolomeu 24]

Ok, here is a new file. This time, I decided to change only the base game files, no CAM, and got rid of the cap part of the mod. This means that only the proximity effect is being tested here, and because there is no CAM modification to the development, Big City Tutorial should work as a good testing ground to check the effectiveness of this mod. So far, the changes in the desirability goes:

R$<->R$$$, I tripled the negative impact between them (eg. "0.000000,-5.000000" becomes "0.000000,-15.000000" instead).
R$$<->R$ and R$$<->R$$$, I just made the impact neutral ("0.000000,-5.000000" becomes "0.000000,0.000000", etc.). That way, both rich and poor Sims wouldn't care about having a medium-wealth neighbor, allowing those to work as the gradient between poor houses and posh mansions.

However, I think the impact isn't that noticieable yet... I think I will have increase the power of the negative impact between R$<->R$$$ to see the results. In any case, if anyone wants to test it, here is the file.

Development Test.dat

 

EDIT:
Tried different values (by simply mutiplying the original defaults by the same number). Apparently, something between multiplying them by 10 and by 20 is where effects start to get noticiable (nothing to see with x10, completely desirability killer with x20). So, a good multiplicative value should be somewhere in between 10 and 20 ; but I shouldn't ignore editing the distance values as well, so far I just left them intact, focusing only on the disarability effect associated with them.

[Propfam 2,288]

On 11/4/2025 at 9:01 PM, Null 45 said:

GeneralResponseCurve. 

What da hell is a GeneralResponseCurve? Is it a curve that response to something? The name is quite sus.

Sorry for necro'ing the topic

[Null 45 3,041]

14 hours ago, Propfam said:

What da hell is a GeneralResponseCurve?

No idea. Whatever it is it appears to be the successor to a HappinessCurve from an older game, likely SC3K based on the leftovers that hint at early SC4 builds having been bootstrapped from that game's data.

[Propfam 2,288]

3 hours ago, Null 45 said:

HappinessCurve

What da f ing hell is the HappinessCurve? I never thought that Mayor Rating is somehow a curve. Maxis is so ridiculous.

[Null 45 3,041]

2 hours ago, Propfam said:

What da f ing hell is the HappinessCurve? I never thought that Mayor Rating is somehow a curve. Maxis is so ridiculous.

I have no idea, it may not have anything to do with mayor rating. The origin of those names are the kind of details that only the original developers would know.