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thanks a lot Catty .......Brian
Thanks once again Cat.....
Y'all know how much I love Peg's work. Peg really likes his network-enabled lots. The marina in particular I have had trouble with. I have not edited the lots themselves to remove the network segments but I have tried removing all TS props from the buildings, I have also tried with various TSEC. Results are very inconsistent. I think it has something to do with not just the TS props but also which base lot was the template. The base marina itself as well as the parking lot I have gotten to behave but the yacht club, sport fishing and guest services nothing seems to work.The problem is that all traffic will divert through the lot. So I have a parallel road running alongside. Congestion will be red on both ends but green in the middle. The lot will of course go red, and in some cases they will even abandon themselves due to commute time (these are CS job lots).
As for my reality assessment about MPH. One last attempt at clarification. If we take all the vanilla speeds and pretend they are in mph, then convert them into kph, the speeds seem more or less realistic. Considering those speeds come out much closer to what has been used in A, B, Z you really can't disagree.
Speaking strictly about cars (well and I guess trucks, but not buses) for the moment...
Of course how does the game see this? Well let's see. Once a car passes through a network tile per simulator run it is there (as far as congestion goes) if it passes the same tile on the trip home, it is there twice. The game takes the total amount of cars passing through a segment per run and calculates congestion as if they were all present at the same time (at least I think it does; it is possible the return trip counts for display but not actual congestion, or doesn't count until the next run at least, who knows).
As far as I can tell (both going by what seems to be generally accepted here as well as my own observations) network capacity in SC4 is per day.
...So what makes some sense then? We could take it as a function of our max commute time, or our max commute time*2, or maybe how many minutes it would take to cross a large (game large) city or just what we consider a reasonable commute period going at said speed. I don't know (yet). It is something to think about.
But I don't understand the abandonment due to commute time - that's a property of residential lots, and you said these were CS job lots.
Yes I can. It's true that the pedestrian speed of 3.5 and the car speed of 31 sound quite reasonable for speeds. And 31 mph quite conveniently translates to 50 kph - exactly the speed used in Simulator Z. But then you get to highways, with a speed of 82, which is a bit fast for a highway. But it's when you hit the rails that this theory really fails. You end up with subways and el rail at 150 mph, which is more than twice the maximum speed of these vehicles. But there is a reason that these numbers are spread out like this, which I'll explain in excruciating detail in an upcoming post.
Yes, you are correct here, and I had considered in my calculations that due to car spacing, speed really isn't directly proportional to volume. However, how much it differs, it's hard to say, and it varies from city to city based on driving habits. In Boston, they drive almost bumper-to-bumper at highway speeds. If you're more than one car length from the car in front of you, someone will cut in. So for simplicity's sake, I've chosen to ignore the spacing effect. Considering that stoplights and stop signs aren't emulated properly at all in SC4, and worst of all, network speeds can drop no more than 30% of nominal, I don't think the spacing effect has much of an impact. The simulator as a whole just isn't that precise.
Your initial statement is correct. The return trip does count toward congestion.This is correct.I'm afraid you lost me here. What's the "it" you're referring to?
My guess is network capacity in the real world and network capacity in the simulator have almost nothing to do with each other.
The spacing effect to me is more just a way to rationalize it somewhat.
The "it" is trying to figure out some kind of formula for "somewhat realistic" network capacity for SC4... And then quite possibly we might just ignore the time completely because in the end it comes down to what works.
There still has to be some ratio to define relationships to keep given simulator consistent with itself.
Been playing with intersection and turn capacity effect. Intersections have a very strong effect on congestion (in the real world). Those effects also reach out pretty far away from the intersection itself. So I wanted to see if I could spread the wealth a bit and I added in extra values. First one, then two. So I wound up with a value of: 1.000000,0.600000,0.700000,0.800000,0.900000
This is pretty much correct; a lot of this follows straight from the fact that population densities in SC4 are much higher than in the real world. Also, a lot of deciding which network capacity is appropriate has to do with personal preference; how much congestion does the player want to see?
But when you have spacing that varies by city, and in some cities (such as Boston) highway spacing is not really different from road spacing, I don't think you can come up with a general formula.
After spending a lot of time trying to do the former, I ended up settling on the latter. I don't think the former approach really works, especially when you take into account varying user preferences.Yes, and it turns out that that relationship is far more important than we suspected, as I'll be showing in that post that I mentioned earlier.
I tried this too, although with lower values. At first, it seemed to work fine. But when I looked at the congestion map and the actual network usage more closely, I found problems. Road squares that had only a few Sims on them (and no subway underneath) on no subway underneath were showing up as completely red. I've long known that the congestion map is slightly buggy, sometimes showing congestion where there is none, or vice versa. Expanding this array apparently exacerbates this problem, at least with the numbers I tested. I would have liked to use a larger array, but in light of these results, I'm going to stick with the current one, at least for now.
Although I agree with everything else you said here; I don't think population density has anything to do with why network capacity SC4 != network capacity real world.
But ok, lets forget spacing...so 3 cars per tile not moving.
I'm a bit confused about the subway bit; I'm going to chalk it up to a typo and you just typed it twice. So it should read "road squares that had only a few sims on them and no subway underneath were showing up as completely red". Correct?
By the way, do subway intersections get affected the same way as any other intersection?
Can you tell me more about the congestion map bugginess? My experiments with the CvS showed me that the congestion map is strongly tied to CvS values.
I'm also still very anxious to hear more about what you meant by applying only to one side (in your last pm).
It's simply that since the buildings contain more people, the networks have to carry more people.
That's RL cars. But over in my development thread, I showed that the actual capacity of all networks is infinite, and you concurred. I believe I mentioned there that that means that vehicles take up no space, because there is no limit to the number of vehicles you can have on a given tile. (Yes, that means that vehicles in SC4 can violate the Pauli exclusion principle. ) To have a consistent world view inside the game, the fact that vehicles actually have zero size has to be taken into account in all calculations.
I'm pretty sure they don't. Each network has a flag indicating whether or not it is subject to the intersection effect, but that flag is somewhere outside of the traffic simulator.When it's working properly, it is strongly tied to those values. But occasionally, certain squares will show something like five Sims on them, yet be completely red, and stay red through many iterations of the traffic simulator. Or a square may be at 150% of network capacity, and show up as completely green. These cases are usually rather rare, though.You might wonder what happens when you have multiple networks passing through the same square. From what I have seen, the congestion display shows the congestion of the most congested network on that square, which makes sense.
What I meant was that the intersection effect applies only to the squares leading up to the intersection, and not to the squares leading away from it. You need either one-way roads or avenues or highways to see this clearly, but it applies to two-way roads as well.
That doesn't change the nature of capacity; it just means more is needed.
This would be a good thing right?
So if you had an intersection of 2 OWR the capacity is only reduced on the 2 sides leading in?
Except how do you tell on a 2 way road which side is which? Even more complicated when you have an intersection of 2 2 ways, which makes it 4 ways.
Or more MT... that's how I prefer to see it...
Consider Manhattan without subways...
In response to my point about the intersection effect being one-sided...It's hard to say. In RL intersections, the effect is asymmetrical, but it is there - vehicles don't immediately resume their top speed as soon as they leave the intersection. But on the other hand, the slowdown is much greater leading into the intersection.
You do this by finding intersections where morning and evening commute traffic is asymmetrical, and by using the traffic volume view and the route query tool, you can verify this effect.
------------ Advice record ------Traffic Jam On Side Street Has Local Sims Stewinga = create_advice_transportation('8bf09867')a.trigger = "game.l_street_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH+15"--game.l_street_congestion_h > higha.frequency = tuning_constants.ADVICE_FREQUENCY_VERY_LOWa.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUMa.title = [[text@abf03875 Traffic Jam on Side Street Has Local Sims Stewing]]a.message = [[text@6bf03879 I've received complaints from several sims on <a href="#link_id#game.camera_jump_and_zoom(game.l_street_congestion_h_subject,camera_zooms.MAX_IN)">this street</a> that the traffic has become unbearable. For some reason, more and more drivers find it necessary to take this route to get where they're going - endangering local pedestrians. You could consider <a href="#link_id#game.tool_plop_network(network_tool_types.ROAD)">upgrading the street to a road</a> to handle the extra traffic, or you could encourage those drivers to take an alternative route by <a href="#link_id#game.tool_plop_network(network_tool_types.ROAD)">building a new road</a> or <a href="#link_id#game.tool_plop_network(network_tool_types.AVENUE)">avenue</a> nearby as a bypass.]]a.priority = tuning_constants.ADVICE_PRIORITY_MED_HIGHa.mood = advice_moods.BAD_JOB------------ Advice record ------Local Road Reaches Limit - A Chaos of Carsa = create_advice_transportation('2bf09aa1')a.trigger = "game.l_road_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH"--game.l_road_congestion_h > higha.frequency = tuning_constants.ADVICE_FREQUENCY_LOWa.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUMa.title = [[text@2bf0387d Local Road Reaches Limit - A Chaos of Cars]]a.message = [[text@2bf03881 Ouch! #city# has been experiencing some serious growing pains lately, Mayor. We've been getting chronic delays and recurring accidents on <a href="#link_id#game.camera_jump_and_zoom(game.l_road_congestion_h_subject,camera_zooms.MAX_IN)">this stretch of road</a>, and more and more drivers are getting road rage. The whole area is becoming a traffic nightmare, and we need to do something to relieve the strain. You could upgrade the road to an extra-wide <a href="#link_id#game.tool_plop_network(network_tool_types.AVENUE)">avenue</a>, which would probably require some expensive demolition. You could make this road two lanes <a href="#link_id#game.tool_plop_network(network_tool_types.ONEWAY)">one-way</a>, but you'd need to be sure you made another nearby parallel road <a href="#link_id#game.tool_plop_network(network_tool_types.ONEWAY)">one-way</a> in the opposite direction. Finally you could redirect the bulk of this traffic, bypassing these crowded roads, by beefing up capacity elsewhere in the vicinity.]]a.priority = tuning_constants.ADVICE_PRIORITY_MED_HIGHa.mood = advice_moods.BAD_JOB------------ Advice record ------Big-Time Traffic Problems Hit Local Avenuea = create_advice_transportation('6bf09be8')a.trigger = "game.l_avenue_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH"--game.l_avenue_congestion_h > higha.frequency = tuning_constants.ADVICE_FREQUENCY_LOWa.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUMa.title = [[text@2bf03885 Big-Time Traffic Problems Hit Local Avenue]]a.message = [[text@6bf0388a It's bumper to bumper out there, Mayor, and <a href="#link_id#game.camera_jump(game.l_avenue_congestion_h_subject)">this particular avenue</a> is in especially bad shape. Every day at rush hour it becomes a virtual parking lot as commuters stew. Perhaps it's time to consider some major upgrades? What if we constructed a <a href="#link_id#game.tool_plop_network(network_tool_types.ELEVATED_RAIL)">rapid transit line</a> to give these drivers an alternative commute? Or you might consider building <a href="#link_id#game.tool_plop_network(network_tool_types.GROUND_HIWAY)">a highway</a> to handle the extra volume. Both are big investments, and you'll need to be sure that you provide proper access, such as <a href="#link_id#game.tool_plop_building(building_tool_types.ELEVATED_STATION)">transit stations</a> or <a href="#link_id#game.tool_plop_network(network_tool_types.HIWAY_RAMP)">highway ramps</a> - to ensure they will be used.]]a.priority = tuning_constants.ADVICE_PRIORITY_MED_HIGHa.mood = advice_moods.BAD_JOB
Those are just constants used in advisor records (e.g. those fluff news that appear in the news ticker window).
I, for one, am interested to see if these changes in these constants result in anything constructive.