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Author Topic: new traffic experiments  (Read 64339 times)

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Offline sumwonyuno

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Re: new traffic experiments
« Reply #180 on: December 01, 2009, 11:50:36 PM »
I wonder who's that friend. ()what()

I'm glad that you'll be working on my region.  I haven't had the time to work on anything Simcity since last Wednesday and I won't have time until at least next week Monday.


The City & County of Honolulu, a Mayor Diary based on Honolulu, Hawai'i.

mark's memory address - I've created a blog!

Offline catty

Re: new traffic experiments
« Reply #181 on: December 02, 2009, 11:00:38 AM »
I meant," said Ipslore bitterly, "what is there in this world that truly makes living worthwhile?" DEATH thought about it. "CATS," he said eventually, "CATS ARE NICE.

Offline ldog

Re: new traffic experiments
« Reply #182 on: December 10, 2009, 11:24:03 PM »
So I figure this thread is past due for an update. (skip down to the bold part if you want to bypass my off-topic rambling and go directly to my on-topic rambling :P )

I'm sure y'all have no doubt seen a few posts in Z's threads (because it is a given that anyone interested in the subject matter here is interested in the subject matter there as well) some of which would carry on into here but there is no point reposting them here as well.

Not much to say about Capitalis. So far I haven't found anything different than Z but I still haven't spent as much time testing with it as it deserves. Intercity commutes throw quite a monkey wrench into the works in general. Things I can easily observe and duplicate with 100% certainty go out the window the minute we add a neighbor city to the mix. In short I don't feel I am able to comment with any accuracy at present time.

I added East Gridlock along next to Gridlockcity so I could learn a bit more in my own sandbox. What I did wind up quickly learning about was a bit more about how the census and workforce drives work. No new discoveries here, it just gives me a better understanding of a lot of what Tage and Nate do, and I actually understand what is said in the CAM related discussions now.

Other things learned along the way that really have nothing to do with traffic. Education and healthcare facilitys are quite inadequate in capacity; even with no CAM and no custom buildings. Recycling center even though the efficiency icon never moves and the numbers reported are useless, they do indeed lose efficiency if you don't plop another down every 25k pop (which also should be raised). Megalots and crime is a joke. Even with a deluxe station plopped down next to them the crime is out of hand. This is even still after modding them to be a bit more effective. Once again nothing new here; it just reinforces points others have made.

Getting back to traffic I've been thinking about capacity more lately. For one thing getting more skyscrapers in really shifts the balance. For another recent discussions with Steve and also some recent rereading of old posts got me more to thinking about reality and how it applies (as well as how it doesn't apply) here. I'm not going to link any of them; most of y'all are no doubt familiar with the relevant threads. One old post that was particularly interesting for network capacity was Jason's thoughts on capacity in the release thread for A&B. It helped me visualize and break down capacity a bit further for myself. Now as Steve is quick to point out, in the realworld increasing speed increases volume and he is quite correct (I may not know jack about traffic engineering but I know a little bit about physics  ;) )

Speaking strictly about cars (well and I guess trucks, but not buses) for the moment; a network segment is 16 meters long. That means at a deadstop we can only fit about 3 cars per lane. Now conveniently our lowest speed is 30% (CvS) so for arguments sake let's say that at 0% congestion (of course 1.3 speed is generally agreed upon so I will have to go back and fix this later) that sims don't tailgate like the rest of us and maintain something of that proper interval Jason mentions so we only have 1 car at a time per lane per tile. That way when we go overcapacity and slow down we can assume people start crawling up each others tailpipes and then we can have more cars on that segement without violating the time-space continuum. Makes sense too. At 85mph (yeah, I got a lead foot) I try to keep as far away as possible from the car in front of me (and I get out of the way for the jerk behind me if he isn't so mindful; and when is he ever  ::) ) yet the more traffic and the slower we are going the smaller an interval I will keep. At 5mph I will ride the next guys arse because a 5 car interval at that speed is just stupid and tends to inspire roadrage in the people around you. With me so far? Good.

Now as y'all remember 1 Km/h is 1.04 tiles per minute. For arguments sake lets just say 1 tile. So we've got 1 car per minute per Km/h of speed. Or 60 cars per hour or 1440 cars per day. Still with me? So with a speed of 50 on a 2 lane network we are talking 6,000 cars per hour. Now if we hit full congestion we are at 30% speed, or 15 km. At that speed we could have only 1800 cars per hour, but since we close ranks we can fit about 5400 cars, and I guess that is close enough that we can fudge the rest (besides none of the preceeding calculations were precise either...I also still haven't corrected for 1.3 speed CvS...in fact that makes it worse, because we actually start at 65 km/h and so 7800 cars). Of course one of the problems with that is to get to that amount of congestion we generally need to exceed network capacity greatly. Quite the paradox on our hands.

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). Not very realistic I imagine. Especially when you are simultaneously going to and coming from work. 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. This means realisticly we could use much higher numbers, but then of course it also becomes much harder to get our CvS curve to do its job.

Then of course we have to think about population density. Especially since I think once again it is agreed that population density in SC4 is much higher than reality. Yet, traffic only calculates 2 trips. Home to work. Work to home. No other trips. The non-working members of the household don't ever go anywhere either. Maybe they even each other out. I know all the little bast...*cough*...darling children on schoolbuses and teenagers with cars going to HS, stupid bit...*cough*...soccer moms driving to/from school and shopping and wherever else they go all day cause plenty of traffic around here. There is a very noticeable difference in traffic patterns depending if school is in or out (note to self: do not buy next house where single main artery is shared with large highschool)

So what makes some sense then?  &Thk/( 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.

Online z

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Re: new traffic experiments
« Reply #183 on: December 11, 2009, 02:28:25 AM »
I have gotten way too behind in this thread.  At least that matches everything else in my SC4 work.  ::)

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).

I addressed this a little in my PM to you, but I'll expand on it here.  Basically, such lots are intrinsically problematic, since what needs to be done to prevent shortcutting depends the environment in which they're placed.

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.  ()what()  If there's only one network present, it should be possible to set a proper TSEC for the lot.  But if there are two or more networks, you may be out of luck.

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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.

Yes I can.  ;D   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.

Speaking strictly about cars (well and I guess trucks, but not buses) for the moment...

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.

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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).

Your initial statement is correct.  The return trip does count toward congestion.

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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.

This is correct.

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...

So what makes some sense then?  &Thk/( 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.

I'm afraid you lost me here.  What's the "it" you're referring to?  ()what()

Offline ldog

Re: new traffic experiments
« Reply #184 on: December 11, 2009, 10:29:09 AM »
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.

 &idea I wonder if those particular lots got some resi prop mixed in. Really it is the only thing left to explain their strange behavior.

Yes I can.  ;D   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.

I knew you would :P
I did mention the sub and el, think I mentioned the highway too :P
I'm looking forward to the excruciating details...sounds...painful  :thumbsup:

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.

It isn't a matter of the simulator not being that precise; it's more like the simulator is way out in left field. 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.

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?  ()what()

My bad, was getting sleepy towards the end.
The "it" is trying to figure out some kind of formula for "somewhat realistic" network capacity for SC4.

For example even though capacity is per day, one could say our day is however many minutes our max commute is. So Simulator Z 1.3 with a max commute of 600 has a 10 hour "day". Of course since the return trip doesn't count towards time but does count towards congestion, we may or may not want to consider the "day" double max commute or 20 hours in this case. We could also look at it as a function of how many minutes it would take to cross an entire city on given network and derive some value from that. 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.

Offline ldog

Re: new traffic experiments
« Reply #185 on: December 11, 2009, 10:27:18 PM »
Oh, almost forgot. Since I had shared it with Steve via pm but forgot I never posted it.

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

As we all know, the intersection tile itself capacity is already halved (at least for an intersection of same networks) so that 1.0 can be read as 0.5, so we go from half up by 10% each tile away up to 90%. I'm sure the values could use more work but the important thing is it doesn't break anything and seems to work properly. I've been using those values for a few weeks now. I have plenty of intersections that overlap each other and it would seem the game just properly applies the highest penalty applicable.

Online z

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Re: new traffic experiments
« Reply #186 on: December 12, 2009, 12:08:11 AM »
My guess is network capacity in the real world and network capacity in the simulator have almost nothing to do with each other.

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?

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The spacing effect to me is more just a way to rationalize it somewhat.

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.

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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.

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.

Quote
There still has to be some ratio to define relationships to keep given simulator consistent with itself.

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.

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

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.

Offline ldog

Re: new traffic experiments
« Reply #187 on: December 12, 2009, 10:14:30 AM »
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?

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. Of course I could be wrong; like I said I don't know enough about traffic engineering. So I am looking at this from a general physics view; which I am also no expert in but I know enough that it makes sense (at least to me)

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.

I've driven a lot of places in the continental US; It doesn't vary much honestly. I'm sure we were all taught various rules of thumb about keeping a proper interval between us and the car in front of us; and yet I would say that very few people follow those rules. Tailgating, regardless of speed, sadly is not the exception; it is the rule. Being SC4 is somewhat more utopian it could be used.

But ok, lets forget spacing...so 3 cars per tile not moving. Now let's look at worst case scenario in the traffic sim, using a road speed of 50 as our example again.
So 50*0.3= 15.  We can only get 90 cars per minute through that road tile (and that is per lane so assuming both directions). That is the absolute maximum. 129,600 cars in 24 hours if that road were used nonstop (and of course with no intersections; no stopsigns or lights, etc). We'd also need to divide it by 3 or 2.5 (depending where your 0.3 mark is) or maybe even 4 or more (because as we've seen capacity is actually unlimited)

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.

Well you can't take varying user preferences into account in 1 traffic simulator exemplar; they either prefer those settings or they prefer some other.
I'll be looking forward to that post.

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.

That's too bad. Like I said I only eyeballed it, I didn't write down numbers and whip the calculator out to be sure. It is possible mine doesn't work properly either, and of course it is possible that the actual values used are the problem. 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).
« Last Edit: December 12, 2009, 10:44:28 AM by ldog »

Online z

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Re: new traffic experiments
« Reply #188 on: December 13, 2009, 12:05:57 AM »
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.

It's simply that since the buildings contain more people, the networks have to carry more people.

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But ok, lets forget spacing...so 3 cars per tile not moving.

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.  :o)  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.

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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?

Yes; apparently the rate of brain cell death continues to accelerate.  &mmm

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By the way, do subway intersections get affected the same way as any other intersection?

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.

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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.

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.

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I'm also still very anxious to hear more about what you meant by applying only to one side (in your last pm).

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.

Offline ldog

Re: new traffic experiments
« Reply #189 on: December 13, 2009, 11:55:51 AM »
It's simply that since the buildings contain more people, the networks have to carry more people.

That doesn't change the nature of capacity; it just means more is needed.

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.  :o)  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.

Yes, but at the same time it makes this all kind of pointless. They couldn't cause congestion if they take up no space either.
Traffic engineering is complicated enough; Quantum mechanics is where I draw the line. :P
(I know, I know, I started it with the time dilation joke  :'( )

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.

Interesting. I have skimmed all the data display tweaking posts of course but I haven't delved deeply into them yet.
I don't think I've seen the effects you describe but then I haven't been on the lookout for them and it is probably easy to miss.
I have been wondering about that, especially with the subway under road if it were added or seperate. I try to avoid running them directly under road so I can view each.

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.

 &Thk/( 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.

Offline RippleJet

Re: new traffic experiments
« Reply #190 on: December 13, 2009, 12:01:48 PM »
That doesn't change the nature of capacity; it just means more is needed.

Or more MT... that's how I prefer to see it... ::)

Consider Manhattan without subways... $%Grinno$%

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Re: new traffic experiments
« Reply #191 on: December 13, 2009, 11:09:56 PM »
In response to my point about the intersection effect being one-sided...

&Thk/( This would be a good thing right?

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.

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So if you had an intersection of 2 OWR the capacity is only reduced on the 2 sides leading in?

That's correct.

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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.

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.

Offline ldog

Re: new traffic experiments
« Reply #192 on: December 14, 2009, 12:31:36 AM »
Or more MT... that's how I prefer to see it... ::)

Me too.

Consider Manhattan without subways... $%Grinno$%

We ()borg() can't! The city grinds to a halt. If they were gone and there were no replacement there'd be more abandonment than you can shake a .09 PH at!

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.

D'oh! Yeah, that's true. I observe it every day on my 26 mile each way commute. The light is green and yet there we sit for many seconds, because these  :angrymore: southerners (love all y'all really I do; just not behind the wheel) cannot find the gas pedal in a timely fashion. When the intersection is really backed up if you are enough cars back you literaly sit there when the light is green and start moving towards it when the light is red  ::) The lights seem to be so poorly timed that the only way I ever see a greenwave effect is if I am the lead car at the last light and no one gets in my way.  ()sad()

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.

I've seen it, especially more noticeable with my longer array.  :-\ I guess since I didn't crunch any numbers I assumed it was just because the assymetrical numbers (I did run querys, just not add them, multiply by intersection effect and check against CvS) were not causing the same congestion. I'll have to check it out, but good find  :thumbsup:

Oh, just a thought from above on capacity, since our vehicles don't take up any space, should they even be required to slowdown at intersections?
And now we bring you simulator Q, the first and only traffic simulator built entirely using Quantum mechanics!  $%Grinno$%

No southerners were permanently harmed in the making of this post

Offline ldog

Re: new traffic experiments
« Reply #193 on: December 15, 2009, 10:19:30 PM »
Was looking through some of my "patches" for things that since there is no doubt I will use them always I am just going to directly modify the games dat files directly.
The fix for the Grand railroad station is contained in an LUA file with many interesting things. Among them are tuning constants for just about the entire game. I thought these were of direct interest:

   --TRANSPORTATION
   tuning_constants.RAIL_CONGESTION_HIGH = 80
   tuning_constants.LONG_COMMUTE = 100
   tuning_constants.SHORT_COMMUTE = 10
   tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH = 320
   tuning_constants.TRAFFIC_CONGESTION_HIGH = 220   
   tuning_constants.TRAFFIC_CONGESTION_MEDIUM =140
   tuning_constants.TRAFFIC_CONGESTION_LOW =40
   
   tuning_constants.AIRPORT_EFFICIENT_LOW =50
   tuning_constants.AIRPORT_EFFICIENT_MEDIUM =75
   tuning_constants.AIRPORT_EFFICIENT_HIGH=90
   
   tuning_constants.STATION_UTILIZATION_LOW =5
   tuning_constants.STATION_UTILIZATION_MEDIUM =30
   tuning_constants.STATION_UTILIZATION_HIGH=60

Oh and also this one:
    tuning_constants.MAX_FREIGHT_TRIP_LENGTH = 256

Now whether they work or not is another matter, and then what the effects of adjusting them if they do work might be...
« Last Edit: December 15, 2009, 10:22:17 PM by ldog »

Offline sumwonyuno

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Re: new traffic experiments
« Reply #194 on: December 15, 2009, 10:43:34 PM »
I, for one, am interested to see if these changes in these constants result in anything constructive.  :thumbsup:


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Offline RippleJet

Re: new traffic experiments
« Reply #195 on: December 16, 2009, 03:28:38 AM »
Those are just constants used in advisor records (e.g. those fluff news that appear in the news ticker window).

As an example,
the following is an extract from the LUA advisor script adv_transportation.lua
(SimCity_1.dat, TGI 0xCA63E2A3, 0x4A5E8EF6, 0xFF7ED4B5):

Code: [Select]
------------ Advice record ----
--Traffic Jam On Side Street Has Local Sims Stewing
a = create_advice_transportation('8bf09867')
a.trigger  = "game.l_street_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH+15"
--game.l_street_congestion_h > high
a.frequency = tuning_constants.ADVICE_FREQUENCY_VERY_LOW
a.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUM
a.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_HIGH
a.mood = advice_moods.BAD_JOB

------------ Advice record ----
--Local Road Reaches Limit - A Chaos of Cars
a = create_advice_transportation('2bf09aa1')
a.trigger  = "game.l_road_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH"
--game.l_road_congestion_h > high
a.frequency = tuning_constants.ADVICE_FREQUENCY_LOW
a.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUM
a.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_HIGH
a.mood = advice_moods.BAD_JOB

------------ Advice record ----
--Big-Time Traffic Problems Hit Local Avenue
a = create_advice_transportation('6bf09be8')
a.trigger  = "game.l_avenue_congestion_h > tuning_constants.TRAFFIC_CONGESTION_VERY_HIGH"
--game.l_avenue_congestion_h > high
a.frequency = tuning_constants.ADVICE_FREQUENCY_LOW
a.timeout = tuning_constants.ADVICE_TIMEOUT_MEDIUM
a.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_HIGH
a.mood = advice_moods.BAD_JOB

Those constants only set the limits (triggers) on when these messages appear.
They have nothing to do with the simulation itself.

Online z

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Re: new traffic experiments
« Reply #196 on: December 16, 2009, 04:20:45 AM »
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.  :thumbsup:

Apparently so - changing them can shut up the advisors!   :D

Offline pepsibottle1

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Re: new traffic experiments
« Reply #197 on: December 21, 2010, 09:23:22 AM »
Sorry to bump this, but I want in. What do I need to adjust the properties in the smiulator?
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Online z

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Re: new traffic experiments
« Reply #198 on: December 22, 2010, 01:03:40 PM »
Your best bet is to use the Traffic Simulator Configuration Tool, which is launched with the NAM Traffic Subsystem.  If you have any other questions on the NAM traffic simulator, please post them in the NAM Unified Traffic Simulator and Data View Help thread.  Thanks! :)