Topic: Split citybuilding levels in more parameters

[Leartin]

Sometimes I read older forum parts for fun. Today, I read about how stations got their individual parameters instead of "level" (cost, maintenance, capacity), and that was an easy change.
I wonder if the same could be done as easily for citybuildings? Currently, "level" defines three things - the placement, the amount of pax, and the amount of mail. With seperated mail-level and pax-level (akin to factories) it would be possible to scale those two values seperately from each other, and independent from the level of replacements. Now, it might not be ideal if city growth causes cities to shrink because a building of higher level has a lower pax-level. But it would allow for empty "breathing room" at higher levels, since skyscrapers too close next to each other usually doesn't look that good. It could also allow for eg. industrial buildings to have a much lower pax_level without being replaced by higher-level commercial buildings, simply by having their level identical.

Granted, that's nowhere near as useful as the breakup of station levels, but if it's not too hard to do, it would still be nice.

[Ters]

I thought their nature as residential, commercial or industrial adjusted passengers vs. mail level, but I can't say I have payed much attention to this aspect of the game.

And industrial building being replaced by commercial buildings seem rather normal for me, although that may be a modern phenomenon linked to post-industrial societies, while I suspect Simutrans does this all the time.

[Leartin]

I thought their nature as residential, commercial or industrial adjusted passengers vs. mail level, but I can't say I have payed much attention to this aspect of the game.

Yes, one has half the mail and one has double the mail. But since all provide the same pax and commercials double the mail, commercials provide more than the other types of buildings. I'd think it more reasonable to share 30-70; 50-50; 70-30, while keeping the same combined amount.

And industrial building being replaced by commercial buildings seem rather normal for me, although that may be a modern phenomenon linked to post-industrial societies, while I suspect Simutrans does this all the time.

I'm fine with one building type replacing another. My issue is that even large factories usually grow in area rather than height. Hence it's hard to have an industrial building that has the same height as a commercial building, and currently, that pretty much means the industrial building would have a lower level. But if there is no industrial building at the highest level, they will be replaced by commercial buildings. If, instead, it had the highest level, but still less pax and mail, it would feel as if it had the lower level, but could not be replaced by commercials. The point of those three building types is to have different areas covered by them, so it would be nice if you could keept an industrial district even at high levels.

[Ters]

My issue is that even large factories usually grow in area rather than height.

Ah. Now I see what you mean. Would it help if Simutrans needed to keep a certain amount of industrial buildings around, so that it can't upgrade to a higher level of a different type just because it feels the need to go to a higher level. On the other hand, maybe it realistically should replace an industrial building with a commercial one only to build another industrial building somewhere else. Some industries are more resistant to moving than others in real life, though. The ones that spring to mind are those built next to rivers and streams.

[Leartin]

Would it help if Simutrans needed to keep a certain amount of industrial buildings around, so that it can't upgrade to a higher level of a different type just because it feels the need to go to a higher level.

Perhaps that would help, yes. Though I'm generally not a friend of this kind of direct solutions, and prefer more basic building pieces, so to speak. To me, having pax_level and post_level appears simpler and more in line with what Simutrans already does, while also being open ended for different uses as well.
(When I want to cut A3 paper in half and need to shop for a tool, I'd prefer a sharp cutter or scissors over a paper-cutting-machine. The paper-cutting-machine might do this one job better and cleaner, but cutter and scissors are more versatile for whatever I want to do next. It's not that I wouldn't want the paper-cutting-machine at some point, especially if there is a lot of paper to cut, but only after I got knife or scissors. Hope that explains my line of thought)

On the other hand, maybe it realistically should replace an industrial building with a commercial one only to build another industrial building somewhere else. Some industries are more resistant to moving than others in real life, though. The ones that spring to mind are those built next to rivers and streams.

But do commercial districts invade and replace industrial districts?
Commercial districts grow where there are a lot of potential customers. This means either close to residential areas to reach those who walk there from home, near tourist attractions which draw people in, or as a commercial district in it's own right once it's so big the customers don't happen to be there, but go there willingly.
Industrial districts, on the other hand, only require basic infrastructure or perhaps a larger goods-exchange-point (eg. a port), and because they don't need much, they tend to go for cheap land. Which, due to pollution of industries, their often subpar appearence and the extra truck traffic they tend to cause, is often land next to industries, since nobody would want to live there.

I'd think what actually happens is that a factory which requires larger amount of space moves from an old, tight industrial district to a new one with more space available, leaving the old space unused. Since the old industrial areas are closer to the city center, they might be more expensive - causing other companies to rather go for the new, cheaper areas. At the same time, space near the center is interesting for residential projects, and if it isn't in the middle of the industrial zone but at it's edge, it's likely that new living space will be made. That, in turn, attracts commercials, makes the area around more expensive and therefore if a factory leaves, no other will come, instead it will be used as living space. Laws might have a hand in that too (dedication of land).
But the point is: That's not a larger commercial building buying out a smaller industrial building which needs to find a new home instead. It's industry leaving, making room for other types of uses. The same often happens with village centers - they build a road around it and a large supermarket at the edge, old stores in the center die out, they become repurposed as living area (or stay a ghost town).

I probably would like a system which would allow "vacant" slots in a city, which could then be repopulated by buildings of lower levels. But that would require a whole different, complex system of modelling tile-worth, connectivity and perhaps even pollution etc. to decide which tiles in a city should be dedicated to which type of building [...] - and we both know that that's a huge project that probably won't ever be done safe for the rare case of a programmer with too much time appearing.

[Ters]

But do commercial districts invade and replace industrial districts?

They certainly do around here (I know of more, but they do not have web pages about them), but it might be that Norwegian industrial districts are much smaller than the world average. It is only industrial districts that are part of a city that suffers this effect, but it is this we are discussing, isn't it? Maybe it isn't so much commercial districts that invade industrial districts as industrial districts that turn commercial, or even residential.

[Leartin]

Your first two examples are about the site of a company that closed down first, and after that the area changed designation. It's not as obvious with the first one (construction began before the company completely ceased to exist) but the second one opened 15 years after the industry closed down.
The third link speaks of gradual change and does not give much information elsewise. Can't read the Norwegian version, seems there are more infos. Would be interesting to know if active factories were relocated in order to build something else, and if so, if that was planned for the area as a whole; or if it was industries going out of business or moving for their own reasons and commercials claiming the empty land.

My point is that it's not as simple as commercial naturally swallowing industrial. Change happens, but if a shopping mall has to close down for lack of customers, it might get replaced by industrial as well. So it's generally okay that designation can change, but I don't like the change in high-level areas.

For the record: That's only one part of the request. I also would like to have parks and plazas even at higher levels, but I don't see how they could generate as much pax and post, given they are practically empty; and I don't particularly like the standard alteration in mail level .com and ind give us. That's three, admittedly tiny, issues that could be solved by two additional parameters with precedence in other objects.
Each could be solved by a dedicated specific change as well - instead of changing mail and pax level in each building, it Could just be adjustable factors for ind and .com. Instead of setting a lower value for parks and plazas, it could just be a parameter that automatically reduced it by a factor of sets it to zero. And for the industrial replacement, you gave options. But That seems like more work over all, I'd still long for those two parameters. Eg. to build a special Christmas post office with large amounts of mail, but hardly any pax (http://www.julenissen.no) It's a silly example, but I'm not the only creative mind in the community. Given the tools, there will always be someone with a new idea how to use them.

[Ters]

Your first two examples are about the site of a company that closed down first, and after that the area changed designation.

And why isn't that the case in Simutrans? I always assumed building being replaced in Simutrans coincided with new owners taking over and having different plans for the site.

[Leartin]

And why isn't that the case in Simutrans? I always assumed building being replaced in Simutrans coincided with new owners taking over and having different plans for the site.

I was more thinking of things like a family with their own house gets kids, needs more room and therefore adds a second floor or something. The graphical representation not showing this so there would be more variety in a city, rather than all levels looking very similar. But that's just my impression.

Especially with Strømmen Stål, that area was empty for several years, it went practically down to level 0 before it was replaced, and should be replaced by anything at any level, not necessarily something "better" -> Strømmen Storsenter could have any level.
Would Olav Thon Foundation have bought (and Strømmen Stål sold) the area if it was not abandoned at the time anyway? I don't know them, and still, I don't think so.

For me, that's a difference. If I have a functioning building, I might replace it by a larger functioning building, but not with a smaller building. Though if there is a catastrophy like a fire, water damage, earthquake,... or a financial catastrophy like a factory with very specific production halls going bankrupt, the 'buildings' might become practically worthless level 0, and even a smaller functioning building would be an improvement.
Again - that's not what I'm asking for (but I would like it). But that's what would represent your example. A building being replaced by one of a higher level is not exactly the same thing, and I don't think commercial buildings generally having higher levels than industrial, and the forced change that comes from it, has anything to do with representation of reality.

[Ters]

Few, perhaps no, building replacements in Simutrans consists of families extending their house to make room for extra kids. That kind of change probably would be smaller than a change in level anyway. A more likely situation is that the kids have grown up and moved out, and the parents figure they don't need such a big building and buys an apartment elsewhere that is easier for maintain with their declining health. They sell their old house. Sometime another family buys it, and nothing happens. Other times, a company buys it, tears it down and builds an apartment building.

Simutrans has no concept of abandoned buildings, we can therefore not say that commercial buildings replacing industrial buildings is a hostile takeover rather than natural redevelopment of vacated space. Just like the construction process is instantaneous, so is the abandonment process.

And I'm pretty sure the commercial buildings/districts I mentioned have higher levels that the industrial ones they replaced, both in terms of number of people visiting the place and the amount of money generated. If the owner of the industry wanted to go to a higher level, they would have to relocate. Aker brygge was sort of a relocation.

[Leartin]

[1] Few, perhaps no, building replacements in Simutrans consists of families extending their house to make room for extra kids.
[2] That kind of change probably would be smaller than a change in level anyway.
[3] A more likely situation is that the kids have grown up and moved out, and the parents figure they don't need such a big building and buys an apartment elsewhere that is easier for maintain with their declining health. They sell their old house.
[4] Sometime another family buys it, and nothing happens.
[5] Other times, a company buys it, tears it down and builds an apartment building.

[1] How would you know?
[2] In pak64 (I assume you wouldn't accept examples from other paks) there is a residential building RES_10_15, which has 14 pax and claims to be home to two families. RES_01_08 looks like  typical size for one family, with 7 pax. If one family can generate 7 pax, we can be generous and say it's actually three generations (grandparents, parents, kids) and about 7 people living there - just to simplify things. But that would still mean each inhabitant contributes one level; kids probably once they start going to school. In other words, a couple getting a kid would raise the level of that building by 1. Note that this wouldn't even require a change in the building, as normally, you don't know from the outside how many people really live in a house - RES_01_08 might as well be used by a single person who uses the complete upper floor as a hobby room.
The same keeps true if we consider each house being representative of a block. In that case, it represents a block of similar houses with similar family sizes, and since each family can get kids, the same concept applies.
[3] I don't see any implication that would be likely. If we consider a house being buildt by a young couple shortly before/after kids come, they would spend about 20 years in that house with the kids before the kids move out (sooner/later depending on culture and special cases). The couple wouldn't even be that old by then, but let's say they do move out after 20 years...
[4] ...and nothing happens when the new couple arrives. Which raises kids for 20 years and moves out due to old age...
[5] ...to finally get a company to buy it and increase the level. After 20-40 years. Probably not by much either, since Simutrans isn't too keen on skipping levels.

So how do you explain changes in building levels with a much higher rate than 20-40 years as soon as there is a proper pax network? Old people moving out doesn't do the trick.

Simutrans has no concept of abandoned buildings, we can therefore not say that commercial buildings replacing industrial buildings is a hostile takeover rather than natural redevelopment of vacated space. Just like the construction process is instantaneous, so is the abandonment process.

In the game, once the top level of industrial building is reached, they get replaced by commercial buildings because they have a higher level. That's what the game does. It's a systematic, one-sided process. It's a game mechanic, one that I don't like and doesn't make sense to me.
You are trying to explain it by saying natural redevelopment of vacated space happens in reality. Before I accept it as an explaination for a systematic, one-sided process turning industrial buildings at a high level into commercials, you'd have to explain why:
A) Only industrial buildings become "vacant" by that mechanic, and therefore can be overgrown.
B) Why only buildings of higher levels can claim vacant space.
Unless there are good reasons for those two that I'm overlooking, I don't think the "natural redevelopment of vacated space" is properly represented by that mechanic, or explains the mechanic, making it still a weird element of game rules that should be removed.

Think of it like this: Assume the game would randomly delete road tiles once in a while. Why would it do that? Your explaination could be that it's streetwork being done (but why doesn't it get replaced automatically?), or that it eroded over time (but why could it happen to new roads as well as to old?), or some other explaination (which probably doesn't take into consideration why it doesn't do the same with tracks)... All of that might be true. After all, it's just randomly gone, so how could we prove that it's not because of this or that reason within the game world? But the true reason is: It happens because the code says so, and there is either no intention to simulate reality with it or it's just a really bad implementation for whatever it should be, either way we would be better off not having it (or perhaps even keeping it, but adjust it so it DOES make sense as streetwork (by being replaced after a month automatically) or as erosion (by tackling only old roads). Not that it would cause joy in gameplay, but that way, it would make sense.

[Ters]

No pak set I have seen contains two buildings which differ only by the addition of a few extra rooms. Simutrans would not see the connection, and know to replace one with the other. In addition, buildings in Simutrans supposedly represent whole city blocks.

In the game, once the top level of industrial building is reached, they get replaced by commercial buildings because they have a higher level. That's what the game does. It's a systematic, one-sided process. It's a game mechanic, one that I don't like and doesn't make sense to me.

It is a game mechanic that represents exactly what I see in real life. Once an area reaches too high a level, it becomes to expensive for industry to stay. Commercial activity takes over, as they are the ones that keep the economic growth going. Whether it makes sense to me or whether I like it, it is what is happening in real life and it is what is happening in Simutrans. In post-industrial Europe, cities are becoming commercial and residential only. What little industry remains are big complexes, typically out in the country side, which are represented in Simutrans by factories. Although even they are dying out in real life.

The city I currently live in was founded on industry, focused on the river, in particular the waterfall. The early industries near the waterfall have now been replaced by shops and apartment buildings. Even the hydroelectric power plant itself was turned into a television studio. (The waterfall still generates electricity, but in another, newer and much smaller building, which likely has a lower passenger level.) The last major industry within what one could call the city (Norwegian cities don't have formal borders, except Oslo), closed a few years ago. It hasn't been replaced by commercial activity, but by a railroad timber terminal and some smaller industries. A bit interesting, since railroad terminals and sidings elsewhere are being replaced by commercial and residential buildings. The city has now reached a higher level of development where it no longer depends on industry, but commerce (and government agencies) to employ its citizens and generate taxes. Maybe capping industrial levels below commercial levels in Simutrans is meant to reflect exactly this. The only thing missing is that the same thing does not affect factories, although that should also involve factories being upgraded, probably to new versions with greater production, but less passengers and mail. A few industries do remain in the region around the city I live in, but quite some distance from the city, and they are doing modern high-tech stuff with fewer workers, so they likely have lower levels than the industrial buildings of old as Simutrans would see it.

[Leartin]

No pak set I have seen contains two buildings which differ only by the addition of a few extra rooms. Simutrans would not see the connection, and know to replace one with the other. In addition, buildings in Simutrans supposedly represent whole city blocks.

So you are willing to suspend your disbelief for one building to represent a block of building, but not for one building to represent an extended version of something represented by a different building before. oô

Once an area reaches too high a level, it becomes to expensive for industry to stay.

I was under the impression that industries own their facilities. They don't rent them, so changes in land value only make them richer in the books. It's not too expensive for industry to stay, if anything, it's too expensive for industry to come after another industry went away for different reasons.
Furthermore, the level only indicates the buildings expansion. If it was land value, it would need to be stored in the ground tile, or new buildings would need to start at a higher level based on their surroundings, because they would be in a high-value-area.

In post-industrial Europe, cities are becoming commercial and residential only. What little industry remains are big complexes, typically out in the country side, which are represented in Simutrans by factories. Although even they are dying out in real life.

We shouldn't mix up factories with industry, that's a whole new bag of worms to open. You need the industrial buildings to represent smaller industries which live in the shadow of bigger ones. Otherwise, you'd need to get rid of commercial districts in favour of end-consumer-shopping-malls as well. (Pretty sure Strømmen Storsenter would be one of those, rather than generic commercial buildings).

But yes: Large industrial districts do tend to form outside or at the edge of cities. And it would make sense if an inner-city industrial district was moved to the outskirts. Either by building a new industrial building outside once the inside building was replaced, as you suggested, or by designating a larger industrial zone and planting higher-level buildings there, while those in the city are abandoned.
Because those new, outside industrial districts are not low-level, they pretty much start out high-level as a grand project, rather than natural growth; or because one large industry is placed there (a factory in the game) and other industry follows. Same is true for commercial centers, a large store is often buildt on the outskirts and other, smaller stores build nearby, creating a commercial district.

The problem here is that there is no representation of that in Simutrans, at all. IF the industries can't pay bills in the city anymore and move somewhere in the countryside, as you claim, then
A) countryside industrial districts should start with higher levels, especially when city-districts get invaded.
B) countryside industrial districts should grow faster than city districts, as they are cheaper (why would there be a switch at a specific level?)

The city I currently live in was founded on industry, focused on the river, in particular the waterfall. The early industries near the waterfall have now been replaced by shops and apartment buildings. Even the hydroelectric power plant itself was turned into a television studio. (The waterfall still generates electricity, but in another, newer and much smaller building, which likely has a lower passenger level.) The last major industry within what one could call the city (Norwegian cities don't have formal borders, except Oslo), closed a few years ago. It hasn't been replaced by commercial activity, but by a railroad timber terminal and some smaller industries. A bit interesting, since railroad terminals and sidings elsewhere are being replaced by commercial and residential buildings. The city has now reached a higher level of development where it no longer depends on industry, but commerce (and government agencies) to employ its citizens and generate taxes. Maybe capping industrial levels below commercial levels in Simutrans is meant to reflect exactly this.

I don't think so. Industrial levels are not exactly capped by the game after all, they could be just as high as commercial or residential buildings. It's just that there are not too many industrial skyscrapers in reality, it's more of an accidential interaction rather than an intended solution to anything. Pretty sure Prissi mentioned at some point that it works if it's done as intended, and showed a screenshot with pak.japan and industrial highrises. So the Intention is to have all types of buildings at all levels. If you go back to the start of the thread, that's what I want to do - just with less pax and post for those high-level industries.

The only thing missing is that the same thing does not affect factories, although that should also involve factories being upgraded, probably to new versions with greater production, but less passengers and mail. A few industries do remain in the region around the city I live in, but quite some distance from the city, and they are doing modern high-tech stuff with fewer workers, so they likely have lower levels than the industrial buildings of old as Simutrans would see it.

That's the situation in Norway. Meanwhile, my closest large city (Linz, the Steel City) has traffic troubles due to all the workers coming in each day, as about a third of the city is industry, most importantly the Steel factory VOEST. The actual core, around the townhall - what would rise highest in Simutrans - is still old buildings. There is practically a ban on any development there, so it's commercials on the main street and otherwise residential, mostly low levels. The highest commercial levels are probably the office towers at the railway station, otherwise, it would be malls like PlusCity - far outside the center.
Perhaps in 50 years, the city won't be industrial anymore, but changed to third and fourth sector as well, while steel is produced somewhere in africa or asia. But until now, it did not.


Once more: The current mechanic is no good. It does not do a good job at representing what you see in it. What you want to be represented could be represented, but the accident that currently exists is not the way to go. And I don't even want to change it per se - all I want is two silly parameters that don't even need to have anything to do with this. There must be some place in the code that says "Set the pax of this building to level*bits_per_month" that I want to be changed to "If pax_level is Null[Set the pax of this building to level*bits_per_month]else[Set the pax of this building to pax_level*bits_per_month]". Why do we need to have a discussion about how industries in reality grow and get replaced just for something as simple as that?

[Ters]

So you are willing to suspend your disbelief for one building to represent a block of building, but not for one building to represent an extended version of something represented by a different building before. oô

I'm not sure where that impression came from.

I was under the impression that industries own their facilities. They don't rent them, so changes in land value only make them richer in the books. It's not too expensive for industry to stay, if anything, it's too expensive for industry to come after another industry went away for different reasons.

It is not that direct. As cities develop economically and level up, it is not that the land becomes too expensive to stay on that forces industries out. Primarily it is the citizens that become too expensive workers. Although I can't rule out that there are cases where factories sell their land to wealthy real estate developers at a high price and build a new factory on cheaper land elsewhere, especially if they need to rebuild most facilities to modernize anyway. In fact, that may be the case for the local power plant.

That's the situation in Norway. Meanwhile, my closest large city (Linz, the Steel City) has traffic troubles due to all the workers coming in each day, as about a third of the city is industry, most importantly the Steel factory VOEST.

But that is a factory, which Simutrans sees as something different. (The oddity of which is another discussion around here.) And furthermore, it shows part of why steel industries are dying elsewhere. Linz, and a few other cities, has gotten an edge to out-compete the rest.

[Leartin]

Primarily it is the citizens that become too expensive workers.

So... because the workers in walking distance become too expensive, industry moves to wastelands with no workers in walking distance? [exaggerated]

But that is a factory, which Simutrans sees as something different. (The oddity of which is another discussion around here.) And furthermore, it shows part of why steel industries are dying elsewhere. Linz, and a few other cities, has gotten an edge to out-compete the rest.

VOEST is just the largest industry. There are many smaller industries around which have nothing to do with steel (or chemistry, given Chemiepark would probably be a factory too). At least those would be citybuildings and fill the whole area in absence of a factory (since Simutrans wouldn't place it correctly)
Interestingly, the city even closer to me (but much smaller), Steyr, is very similar to Linz. Instead of steel, it's motors and vehicles. Again, if Steyr was in the game, it would have a car factory or car-parts factory, but also a lot of other, smaller industry.

We could also play this game the other way around. You talked about an Hydroelectric PowerPlant as industry - in Simutrans, it would be a PowerPlant factory. Strømmen Stål, the industry area replaced by a shopping mall? A factory, of course. The mall itself? Why, an end-consumer factory. All arguements about com replacing ind become invalid if you start seeing them all as factories, and as long as either goods are consumed, produced, or both, it's a valid point of view and negates the whole discussion, perhaps even the existence of ind.
But, since it's a game about transportation, we could just assume that "factory" and "industry" both represents the same thing, except that factories look for an outside contractor to deliver their stuff, while others don't. Maybe they have their own delivery trucks, maybe they don't have enough output to warrant their own transport (so it counts as a mail package), perhaps the others are in a Keiretsu and don't do outside business, or they deliver/consume to/from other ind so close by, the scale does not allow it to be represented (walking pax -> walking package). If so, size has nothing to do with it, and whether a real factory is a factory or industry ingame would be undecided. Makes sense to me.

As for your point that Linz is "steeling" other cities industries - sure, perhaps, the steel industry of some places might suffer. I don't really think Steyr, despite the same concept, would really influence norwegian cities too much - at least not on it's own. So even if there are some strong industrial cities with specific industrial branches which weaken industry in some other cities, there would still be a lot of those industrial cities. Other cities boom on tourism, others on finances and computers. Which would warrant a mechanic to distinguish the growth of different types of cities, but still - why would the current mechanic represent Oslo, but not Linz? Wouldn't it be better if both was possible?


Possible ideas to have better representation? (wishful thinking, not a request, unlike the extra level parameters)
- Industry could produce "packages" which work like mail or pax, but are only produced and consumed by industrial buildings (and perhaps factories). Those "packages" could be a special good or piece good [actually... if post or pax were defined as different categories, would that work?] - either way, they show that industry consumes and produces, just not at a scale large enough to warrant destinct representation of the goods in question.
- Factories (and curiosities) could have the subtypes "ind", "com" and "res". If so, they would attract citybuildings of that type IF they are close enough to a city. At the same time, city-factories and city-attractions could be reprogrammed to spawn within a tight radius around the city as well - causing satellite-districts of specific designation. If a different [!] mechanic appears that replaces inner-city industrial with commercial or residential, the factories (or curiosities) would protect that from happening. (Essentially: Linz is an industrial City because it has the steel mill, so industry in general thrives. RandomCity has no factory, so their small industry will be replaced over time.)

[prissi]

I suggest you to look at a typical post-industrialised country like England or many parts of the US. No factories near city centers, all in and between the suburbs (the few left).

In pak64 the commercial and the industrial levels are balanced, so that until 1920 or so you get as much industries as commercial levels. Later in the 50ies and 60ies, the commercial levels win. For pak64 Japan the balance is more even, since you find high rise appartments and commercial buildings next to industries even nowadays.

The problem of how to protect old towns (a very Eurocentric problem, here in Japan just five month ago they leveled a 100 year+ old building to extend a parking lot), this problem has discussed several times. One idea was to have a parameter that forbid further development, whenever a spawned building is older than xxx. Although cities like Frankfurt or the Ruhr vally (where industry died and which were almost completely destroyed by war) define even this.

And in OpenTTD cities consume goods, which can be just dumped in any stop in a city.

Since the level was introduced to get more variety and only later was interpreted as inhabitants, I think with three categories and a level plus clustering plus city rules, the city growth is already complex enopugh with lots and lots of paramters to screw on.

If ever, I could think of a "protected_building=1" parameter in dat files, that forbids further renovation once this building spawned.

[Ters]

All arguements about com replacing ind become invalid if you start seeing them all as factories, and as long as either goods are consumed, produced, or both, it's a valid point of view and negates the whole discussion, perhaps even the existence of ind.

It might be that commercial city buildings get integrated with end consumers, but such details are for that other discussion.

Wouldn't it be better if both was possible?

Sure, but you can't have both at the same time, not with building levels alone, split or otherwise. Although splitting passenger and mail production from the development/replacement level will make it possible to simulate the fact that industries start having fewer, or at least not more, workers per area as automation kicks in from the late 20th century (unless it is some very light-weight industry that can be stacked in height).

[Leartin]

Sure, but you can't have both at the same time, not with building levels alone, split or otherwise.

No, but another feature you'd need is already in the game: Climates. You could have both in the same game if there are some climates with high-level industry and some without. Furthermore, country-specific paksets might display either post-industrialised countries or not, so even if they don't use both, it would be good for those to have options.
(Let alone that the first thing I'd do with these parameters wouldn't even be about industry at all...)

[Ters]

This isn't really climate dependent.

Whole pak sets doing things differently already exists according to how I understand prissi, which is why I said you can't do both at the same time.