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Version 1.0.0
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The Park And Ride Traffic Simulator Plugins are modified versions of the NAM's latest and greatest Simulator Z 3.0 Traffic Simulator Plugins (last updated with NAM 45), with one key difference: the Car transit type has its "Travel type can reach destination" property set to "False". This means that Cars cannot directly reach their destination, thereby requiring Sims to use Parking Garages or Parking Lots, or use alternative forms of transportation, like mass transit or active transit (walking) to reach it instead. All NAM Park And Ride Traffic Simulator Plugins are labeled as "Simulator ZP" to distinguish them from the standard, non-Park And Ride Simulator Z files in the NAM. While this package can technically act as a standalone, we recommend using it with either the full Network Addon Mod or NAM Lite, to have a fuller SC4 transportation experience. IMPORTANT! Installing this Plugin but failing to provide parking or alternative forms of transportation may lead to significant changes in the behavior of existing cities, so one should either take care to retrofit those existing cities with the necessary infrastructure (parking lots and/or mass transit), or one should consider starting a new city/region. Further details on the operation of the standard edition of the NAM Traffic Simulator Plugins, including more information regarding capacity levels, network/transit type speeds, and other details can be found in the official feature guide at sc4nam.com. Compatibility and Installation (Short Version) The minimum requirements for running the NAM Park And Ride Traffic Simulator Plugins are as follows: A compatible retail copy of SimCity 4 Deluxe Edition OR SimCity 4 with the Rush Hour Expansion Pack Windows/Linux (via WINE): Any digital retail edition, or any disc copy updated to at least Version 1.1.638. macOS: Any recent digital edition of the Aspyr port for macOS (installation on the App Store version is more difficult, and the NAM Team is limited in our capacity to provide installation help to App Store users). The now-rare non-Deluxe/non-Rush Hour copies of SimCity 4 are not supported. Attempting to run the NAM Park And Ride Simulators on a non-Deluxe/non-Rush Hour copy of SimCity 4 will cause the game to immediately crash to desktop (CTD). A system with the following specs: Any system which can run SimCity 4, with 40MB available disk space. Java Runtime Environment (JRE), in order to run the installer. (The Java Development Kit, or JDK, will also work, but contains extra files not needed unless you're a Java developer.) Adoptium's open-source edition is recommended, though JRE and JDK can also be acquired in proprietary/commercial (but free to download) form from Oracle at https://www.java.com. Additional Requirement on Mac (optional for Windows/Linux): JDatPacker by memo. JDatPacker is a tool for consolidating folders of SimCity 4 plugins. This can speed up the game's performance, and on macOS, this helps alleviate issues with the Aspyr port's known "number of files limit", wherein exceeding a certain number of files/folders within the game's Plugins directory can cause the game to crash. To install NAM Park And Ride Traffic Simulator Plugins: Install the Java Runtime Environment (JRE) (if already installed, skip to Step 2). Run the NAM Park And Ride Traffic Simulator Plugins Installer (NetworkAddonMod_ParkAndRideSimulators_Setup_Version1.jar). Follow the installer's instructions, clicking on each tab on the top bar in order. Agree to the mod's terms on the initial "welcome" tab to proceed with the installation. select the options you would like to install under the "files" tab. Select the install location under the "location" tab. Unless you have set up an alternate location for your Plugins folder, or happen to be on the Mac App Store version of the game, this should Use the "setup" tab and run the "cleanup" feature to remove any conflicting Traffic Simulator Plugins (NAM or otherwise), such that the Park And Ride settings are applied in game. Finally, move to the "install" tab. Click the "Start installation" button to begin the installation process. When the installation is complete, the progress screen will display a message, "All selected components installed!". Close the installer, using the "X" button or, on macOS, the red circular button, in the upper right corner of the window. You're all done installing the mod. Load the game and enjoy the NAM! Manual Installation - Advanced Users who are unable or unwilling to install Java can perform a manual installation of the NAM, something which the new file architecture introduced in 2020 makes far more possible than the previous "Monolithic" releases. This method requires a file decompression tool capable of opening .jar files, such as 7-zip (Windows) or Keka (macOS). To begin, open NetworkAddonMod_ParkAndRideSimulators_Setup_Version1.jar using your file decompression tool. The Park And Ride Simulator contents are located in the "installation" subfolder. The current installer uses a series of character flags at the start of directory names, in order to instruct the installer how to order the options, whether they're mandatory or optional, etc. Numbers preceded by the at sign ("@"), i.e. "@1", "@2", etc., are merely being ordered with this flag. Any directory with the caret ("^") in front of the name (or behind a "@" ordering flag) is mandatory. Any options where the equal sign ("=") and the dash ("-") are present are mutually exclusive--only one should be installed (the "=" option is the default). Remove any existing Traffic Simulator Plugins from your Plugins folder first, then copy the desired capacity level (Classic, Low, Medium, High, or Ultra) into your Plugins folder. The cleanup.txt file in the root of the .jar file can provide you with a list of conflicting file names. DO NOT INSTALL MORE THAN ONE OPTION. A Note Regarding The Former Traffic Simulator Configuration Tool (TSCT) The NAM's Traffic Simulator Configuration Tool (TSCT), first introduced alongside NAM 31 in March 2013, was officially discontinued with the introduction of Simulator Z 3.0 in NAM 45, released in September 2022. Further research conducted on the traffic simulator by z resulted in discoveries that some of the simulator parameters that had been modifiable in the TSCT, such as network capacities, were far more sensitive than previously thought, and that use of the TSCT could significantly degrade simulator performance to unacceptable levels. The tool also required significant reprogramming, as a number of features with it did not work as intended, and there were also difficulties with being able to recompile it from the source code that was available. The settings modifications to create Park And Ride options do not degrade NAM simulator performance, and as such, this package exists to make up for the fact TSCT had been the easiest way for the average user to use the Park And Ride settings for the simulator. Previous efforts to include Park And Ride options in the NAM installer itself resulted in a number of users complaining after accidentally installing Park And Ride simulators, which led to their relegation to the "Park And Ride" checkbox in the TSCT. The only other simulator parameters that are safe to modify from the out-of-the-box NAM settings are the Monthly Fares per Sim per Tile and Monthly Costs per Network Tile properties. As the TSCT is officially discontinued, given that it modifies parameters that degrade the NAM's Traffic Simulator, no technical support will be provided to users who still utilize it. Other modifications to the NAM Traffic Simulator's settings performed with other tools besides the TSCT are also at the user's own risk, and the NAM Team cannot provide technical support, nor will the team assume any responsibility for any resultant issues. More details about decision to discontinue the TSCT, on a property-by-property basis, can be found in the Traffic Simulator Features Guide at sc4nam.com. Distribution and Old Versions The NAM Team only provides support and allows distribution of the most recent NAM version. The same is true of the NAM Park And Ride Traffic Simulator Plugins. Users wishing to hold onto old versions should back them up in their personal archives. Note again that no technical support will be provided for this, nor may any user or site redistribute any old versions. Network Addon Mod - Credits The following named members of the major SimCity 4 fansites and Discord servers have, for whatever particular reason, been specifically included here for their special contributions during the NAM's history. Very special thanks goes towards them in the making, supplying, &/or supporting of this mod &/or its contents possible in one way shape or another: z - Main Simulator Developer Lucario Boricua - additional major research mott - early research/initial Park And Ride concept jplumbley - early research the7trumpets - early research Tarkus - 2023 Park And Ride modifications and release engineering Ulisse Wolf - additional release engineering support Daeley - original Java installer design b22rian - Simulator Z testing pierreh - Simulator Z testing NAM Founders Redlotus the7trumpets Tropod NAM Team Lead Tarkus NAM Technology Evangelist Haljackey NAM Logo MadSim (original design) Ramona Brie (updated design) Special Thanks Webmaster & administration staff at Simtropolis, SC4Evermore, SC4Devotion, ModDB, and SimCityPlaza. All (other) members of original Simtropolis Modd Squad, especially the Modd Squad founders. And possibly others who may not have been mentioned. If your name has been forgotten or you're not on the list, then drop us a line, as it has been difficult to keep track of anyone/everyone that may of helped somewhere along the lines. And to the community itself, we would also like to thank you for your support, making mods such as this possible too. We're still at it after almost 20 years thanks to you! And last but not least, a thanks for the Maxis individuals too, for the [paid] work that they did and released 20 years ago. Here's to 20 more. ;-)- 3 Comments
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A thought came to me today - is there any merit in building avenues and highways early on, before there's enough traffic to actually justify them, just to provide a faster road speed for sims to reach job markets? I ask because I'm trying to find ways to get Sims to commute as far as possible to reach a Downtown office area, in order to create a more realistic, low density LA-style urban-sprawl, and I'm assuming standard roads, with their lower speeds, would lead to commute time abandonment in the suburbs.
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Revisiting the Traffic Simulator: Multimodal Transportation Opportunities
Lucario Boricua posted a topic in NAM & Transit Networks
Today I want to announce a special project for the Network Addon Mod, we'll re-visit the Traffic Simulator to refine it and tune it for multimodal transportation behavior! To carry out this project, we'll be forming a focus group consisting of both players, and NAM team members and associates alike. My intention is for us to test out which variables need adjustment to recreate more realistic commute behaviors in settings with significant transit availability, while also keeping undesirable commute behaviors at a minimum. Results from this testing may lead to development of new NAM features for everyone's enjoyment. How to get involved: community members interested in participating can post publicly in this topic, contact me directly through private messages (Simtropolis and SC4 Devotion), or through the respective Discord servers of ST, SC4D, and Rob's Red Hot Spot. Depending on the interest and skill level, I can arrange the provision of pre-edited versions of the Traffic Simulator files, or teach the participants how to edit the changes in themselves. Required tools: either iLive Reader 0.9.3 (link here) or SC4 Reader 1.5.9 (link here) Useful resources: Tutorial: Understanding the Traffic Simulator, (SC4 Wiki article) by @z1 Topic: A Guide to the Operation of the Traffic Simulator, (SC4 Devotion forum topic) by @z1 A Guide to the Operation of the Traffic Simulator, (Simtropolis forum topic) by @z1 NAM Unified Traffic Simulator and Data View Help, (SC4 Devotion forum topic) by @z1 Which variables of the traffic simulator are we experimenting with? Network speeds of the travel types: the traffic simulator defines the speeds of the various travel types (the travel modes) on each network. For the first round of experimentation, we will focus on the speeds associated with street transit types, namely pedestrians, cars, buses and freight trucks. Of interest is making streets meaningfully distinct from the other surface road networks. At present, I'm aware numerous players ditch streets altogether, as they treat them as inferior roads in terms of their functionality. A slight increase of pedestrian speeds and decrease of motor vehicle speeds can have positive effects in realism of travel behavior. This can minimize rat running (cars using local streets to bypass congestion), routing of buses and trucks only along higher hierarchy roads (more realistic bus and truck routes), and increasing the catchment area of transit stops (thus more realistic bus and train station spacing). A derivative project which could be done with these tweaks is creating a second override system for Streets, without motor vehicle paths, to create a draggable pedmall system. Trip Starting Cost by Travel Type: the traffic simulator can add time penalties or handicaps to starting trips using a particular mode or Travel Type. Of interest is tweaking the starting cost for car trips, as this can mitigate the issue in which car trips outperform walking in super short distances, and at the same time increase the catchment area of transit stops, specifically in the vicinity of the residential areas and the start of commute trips. Adding pedestrian paths to rail networks: as crazy as it sounds, there is a possibility of creating entirely new networks by adding or removing paths as part of an override system, while also setting different speeds to those used in the networks traditionally associated to them. This area requires bigger modifications elsewhere, but it remains as an option to expand the game's capabilities. Projects similar to this concept include the Hybrid Rail (dual networking of rail and monorail/HSR, including paths for both), the Real Highway (removing pedestrian paths from the Dirt Road, to create a versatile and realistic freeway/motorway network), and the Subway RHW FLUPs (overriding subway with Real Highway). My proposal in this area is using the Elevated Rail to create a cycling network through an override system, such that we could use the El-Rail tool to build a network with pedestrian paths and set to support a significantly higher speed than the walking speeds programmed into the surface road networks (Street, Road, OWR, avenue). We still need to research if such configuration even works, as there's known issues with incompatibility of certain networks with paths other than those explicitly intended for it. How will testing start? We'll start with the first two topics, network speeds of the travel types and trip starting cost by travel type. With these two tweaks, we expect to modify commute behavior in the game to recreate more realistic transportation behavior for pedestrians in multimodal transportation networks. Additionally, players who want to recreate pre-modern cities before motor vehicles and railways became a thing can also benefit from our findings to do their respective traffic simulator tweaks. Gonna provide the full batch of modified Traffic Simulator Z capacity options here for all players, for those who haven't done the modifications themselves. All the files uploaded here correspond to Test Battery A, make sure to mention that whenever you post screenshots and your observations on the results. These files are available for any player interested in participating, we look forward to seeing your results and experience! NetworkAddonMod_Traffic_Plugin_Z_TestA_Classic.dat NetworkAddonMod_Traffic_Plugin_Z_TestA_High.dat NetworkAddonMod_Traffic_Plugin_Z_TestA_Low.dat NetworkAddonMod_Traffic_Plugin_Z_TestA_Medium.dat NetworkAddonMod_Traffic_Plugin_Z_TestA_Ultra.dat- 12 Replies
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Hi, I am working with SimCity 4 on a mac computer with OS Big Sur. I have downloaded the NAM39 with the Traffic Simulator and it is working fine. What I would like help with is buses. Not sure what I clicked on but the buses have taken over. Does anyone know how to remedy this problem in the traffic simulator? I use the buses I don’t want to eliminate them just decrease the amount of them. Thanks
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Guys, I'd like to know if there is any .txt file or some kind of a log generated after running a NAM traffic simulator-outfitted copy of SC4. I can't find any file like that. The reason I need it is that I am not sure if my traffic simulator works fine... Here's a screenshot from one of my towns: I use "low" NAM traffic simulator settings and can't shake the feeling that: 1. The traffic from the top of the image should use the road marked with question marks... 2. ...converge with the other vehicles on the road at the bottom of the image... 3. ...then, continue to the industrial district. Ergo, use the fastest route, not the shortest (though sometimes shortest=fastest, no doubt.) Instead, a lot of cars are actually using a street at the top of the image to drive past the bridge and into the industrial sector. Is that okay? What do you guys think about it?
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I honestly can't think of any other reason. The problem with this logic is that it just doesn't work that way. It doesn't matter what sort of vehicle is used, there will be noise, whether it is generating traffic or not. You can set every transit type to not create traffic, and you will still have the exact same road noise for Residentials and customers for Commercials. So there is no possible benefit to including buses as traffic, period.
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I'm working these days on a new traffic simulator by using the Traffic Simulator Configuration Tool. My goal is to create a simulator which will be suitable for futuristic cities, by taking into consideration various technological advancements and possible social scenarios. I already have some ideas, but since it's my first time of working with TSCT I'll need some help and advises. This is my very first attempt. Take your time to study it, if you wish. Now that you have seen the numbers, please let me explain my concept and my reasons behind those numbers. For an easier reading, let's separate them into technological aspects and social aspects. Cars and mass transit of tomorrow will be clean, quiet and intelligent. They'll use electric batteries or hydrogen fuel to move around without polluting the environment, their engines will be more quiet, and they'll also be equipped with sensors and AIs and share information with each other to avoid traffic jams and collisions. And yes, the above technologies right now are under development. This is my attempt to make those technologies available for my Sims. Vehicle Air Pollution is on 0.00 to represent electric or hydrogen-fuled cars. Oil dependency and air pollution can now die in a fire. Intersection Effect Multiplier is on 0.2. Let me explain why. Cars of tomorrow will be autonomous, thanks to computers and sensors. All you have to do is to give your cars your destination and your car will transport you wherever you wish, without the need of driving. But why stop here? By giving our cars the ability to communicate with each other, it will be possible to detect and avoid each other, reducing car accidents to zero and even making traffic light and sights unnecessary. So the intersections of tomorrow will be like this... ...but even saver, thanks to self-driving cars. That's why I've reduced IEM to the minimum possible. Cars will still have to slow down a bit, but they'll not have to stop if there is no car close to them. No change to Customers/Traffic Noise Coefficient yet. Cars of the future will be quiet, but I don't want to ruin my commercial zones. On the other hand, I can simulate the lack of sound pollution by better organization of the city, like planting more trees and moving my commercial zones to new places. OK, I'll need some advises here. How can I reduce sound pollution without reducing my commercial zones? Which number you think is the best one to try? We can predict the technology of the future, but how about the society of the future? Predicting the social evolution is more tricky and there are tons of predictions about it. We can't know the way of thinking and acting into the future, but we can still imagine it. My game takes place in a money-free, post-scarcity future. My Sims have access to whatever they need, without the need of money and working and without worrying about taxes and unemployment. Machines are making all the hard work, allowing my Sims to do whatever they want and pursue more meaningful things. So no poor and rich Sims, and no need for tickets. Free access for everybody to everything. And if that sounds like socialism/communism, it's not. It's resource-based economy and it's more realistic and plausible than you might think. This is my attempt to simulate post-scarcity for my Sims. Mass transit will be an even bigger thing into the future, especially in a post-scarcity civilization. It will be possible to build cities designed to encourage mass transit. But cars will still exist even then, although they'll be not as mandatory anymore. To simulate this, I'm playing with the Mass Transit Usage numbers. I've put all my money to the Fastest value, giving my Sims the freedom of choice. I'm afraid however that this is a bad idea. What if all Sims in a small city find my magnetic railroad so useful, that my trains will be more like cans with sardines? Yeah, too risky. Here is another part I'll need your advises. Which is the best strategy to encourage mass transit, while still giving my Sims the option of taking a car? Remember that we're talking about a society with no economic classes, so this strategy should be used by everybody. Monthly Fares to all types are 0. Remember, free access to everybody. I also hope it will encourage my Sims to use my mass transit. Highway Bus Lines has been activated. I want to make my buses even more useful and maybe simulate taxis, free public cars or some kind of share-your-car program. And something personal. I really want to activate the Park & Ride protocol, but then I'll have to pick some nice parking lots and relot them, to make them compact and underground, in order to not sacrifice too much land for parking. We'll see... What do you think? What would you suggest me? I haven't saved and tested this traffic simulator yet, but I'll do it ASAP. Any idea and advise will be welcomed.
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Does the NAM traffic simulator load balance?
MarkShot posted a topic in SimCity 4 General Discussion
I know the fastest route is always chosen. Is that the fastest route absent of congestion considerations? Or is that the fastest route given current traffic conditions? I ask, because * I am doing a region. * I have followed this approach: ** HSR for inter-tile transport. ** Ground rail for inter-tile freight. ** Roads for intra-tile freight and transport. (no roads cross tiles) ** Workers move by bus (and in high density tiles) by subway too. --- So, I am thinking of putting in some cool NAM highways like a 10S or 8C. But I am thinking unless the highway connects someplace theoretical faster or I exclude some HSR connections; if it is the fastest route without congestion consider, then either my HSR or highway will sit unused. So, can I get traffic balanced across major arteries or should I be very careful not to make them parallel? Or will I get traffic because $$$ workers will prefer to drive? Sorry, I know I sound very confused. I just want some tips before I start laying asphalt. Thanks! (see below for what I am talking about) -
I started a new region recently. Made cities in all the tiles a brought up the population to about 10,000. About half way through I made changes to the Traffic Simulator Configuration. Now when I go back to the cities that were started I get mass unemployment, and new roads and streets never get used. (They never show up in traffic view either.) If I demolish the city tile and rebuild its all fine. I remember reading about this before, but cant seem to find the answer when searching.
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I recently updated NAM and subsequently the traffic simulator and it seems I can no longer make any changes to my traffic simulator configuration. I load the file from my plugins folder, edit it drastically and save it successfully. I run the game for a few years and there is no change in that time. No changes in maintenance costs, fare income, transit usage or anything. Very strange and making it very difficult to get my city to actually scale. Any help would be fantastic!
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A Guide to the Operation of the Traffic Simulator The traffic simulator is one of the least understood components of SC4. This is partly because understanding of how it works is not required for modding other parts of the game, and partly because many of its effects are fairly subtle, and are often second- or third-order. This guide will attempt to summarize our current knowledge about the traffic simulator, both in terms of how it works as a whole, and also in terms of what each of its individual properties do. Since it is the properties of the traffic simulator that are accessible to us, and that allow us to tune it in various ways, these properties will form a central part of this description, and will be boldfaced whenever they are used. This post contains some material from other places; I have gathered it all together here for ease of reference, and also to make this description more coherent. There are undoubtedly some errors in here, and some omissions; if people spot these, please post in this thread, and such errors or omissions can then be corrected. This guide has not been written in isolation, and in fact relies to a very large extent on previous work done in this field. Specifically, much of our current understanding of the traffic simulator has come from work done by the7trumpets, Tropod, jplumbley, and Mott, among others; what I have done has merely been to build upon the excellent work done by these gentlemen, and would not have been possible without their efforts. Most people are aware that changes various parameters in the traffic simulator can have a significant effect on their game, but it's often not obvious how significant that effect is. Consider the following Pop & Jobs graph: This is a graph of the Lakeview neighborhood in the city of Chicago. Lakeview was originally built with a pre-alpha version of Simulator Z; it had the large capacities and long commute time of today's Simulator Z, but it still had the pathfinding heuristic (PH) of its CAM Simulator predecessor. (The pathfinding heuristic will be discussed in detail later.) It was quite stable in this state, which you can see at the beginning of the graph, where all lines are basically flat. The city in general looked pretty good and seemed to to function rather well. At this point there were just a couple of city blocks where there was a lot of abandonment and rebuilding going on. I eventually realized that I needed to adjust the PH, which I lowered to the value of .003, which was thought to be the perfect pathfinding value at the time. This is the point where the R$$ starts to rise rapidly and the R$ begins to fall rapidly; there is also a slight upward movement in the CS$$$. All this represents upgrading; either buildings that were originally R$$ but downgraded to R$ were upgraded back to R$$, or new R$$ buildings replaced existing R$ buildings. Throughout all this, total population remains steady at around 835K. A very important point to note here is that though the population of the city was changing significantly, as evidenced by the graph, I was unaware of the extent of the change at the time. Only since the end of October, when I began doing the PH experiments that are illustrated in the Traffic Simulator Z Development and Theory thread starting with this post, have I even been aware of these population changes. And yet their significance is obviously great; the difference in residential desirability that they represent has a profound effect on the game. But these changes aren't always accompanied by abandonment, and are therefore easily missed. Similarly, if a player uses a traffic simulator that is not properly tuned, there are no changes to see; there is just a general lack of desirability and its attendant effects that are difficult to explain. Rarely is the traffic simulator thought of as the cause of these problems. Returning to the graph, look at the point where the red arrows are pointing. This is where I switched the city from Simulator Z v1.0 to v1.2. The changes in v1.2 included reducing rapid transit speeds, adjusting the Customers/Traffic Noise Coefficient, and strengthening the travel strategy preferences of the Sims. The changes in the graph here are more subtle; some take a while to kick in, while others are immediate. The general trend of the R$ and R$$ lines does not change immediately. However, within a decade the trends accelerate until they cross at a point where they are both close to the vertical. Major changes are clearly happening in the city here, yet without seeing this graph, they would not be obvious. At this point, both the PH change and the changes introduced in v1.2 are working together constructively to produce these steep trend lines. From experiments in the thread referenced above, it was shown that a PH change tends to work itself out in about 30 years. In the graph, that's right where the top two trend lines angle sharply toward the horizontal. The R$$ remains fairly constant through the remainder of the run, while the R$ continues to decline; the population as a whole remains steady. From here on out, low-wealth Sims are being replaced by high-wealth Sims. Meanwhile, the changes in the R$$$ line begin right at the simulator switch; there's an immediate little bump that quickly turns into a steady upward trend that lasts through the remaining 60 years of this graph. The net result of the movement of all three populations is that in just a few years following the change in simulators, the city's overall population jumps by about 7%, from 835K to 894K, a level at which it remains at for the rest of the graph. There are significant changes in the commercial capacity as well. (The city has no industrial population to speak of.) The third red arrow shows the CO$$$ capacity, which has been flat until now, but immediately increases during the few years after the switch. It settles back a little bit, and then maintains roughly the same level for the remainder of the run. Meanwhile, directly below the red arrow is the CS$$$ line, which has been slowly rising since the introduction of perfect pathfinding. But with the changeover to v1.2, the rise accelerates noticeably for a few years, and then slows down, though it continues to rise through the end of the test. Changes like these are much easier to see in a small graph like this than by eyeballing the city for a century. Some of the most dramatic changes come with the introduction of v1.2, well after the PH has been lowered, so there are clearly other factors at work here. Later, the perfect pathfinding heuristic was changed to the more accurate value described in this post; this caused the previous changes to continue on for a little longer. To understand what these changes are and what their importance is, we have to really understand how the traffic simulator works, and that is the subject of the rest of this post. First of all, it is important to note that despite its name, the traffic simulator isn't actually the part of the game that simulates traffic, at least as it is visible to the players. Visible traffic is generated by the automata controller, which is only loosely influenced by the traffic simulator. Aside from the automata, there is no actual traffic in the game. Instead, the traffic simulator runs about once every four game months, and calculates routes for the Sims to take to and from work. This is why if you use the Route Query Tool on various networks, the numbers will always remain constant for months at a time. No one travels the morning commute routes in the morning, and no one travels the evening commute routes in the evening (other than the automata). These routes are calculated mainly for their side effects, which are used by many other aspects of the game. Most importantly, they are a key factor in determining desirability, which is one of the most important factors in deciding how the growth of cities will proceed. To a very large extent, then, the traffic simulator is actually a desirability generator. The functionality of the traffic simulator can be divided into six parts: The destination finder, which locates suitable jobs for working Sims. The pathfinder, which calculates paths from the Sims' homes to their jobs. The automata support, which provides data that allows the automata to reflect something of what is happening in the game. Properties that affect only the city's budget. Properties that are either unused, or serve a purpose that is currently unknown. Properties that are known to be nonfunctional. The first two of these functions are the main reasons for the traffic simulator's existence: to find jobs for the Sims, and to calculate paths to these jobs. As mentioned, these functions run about every four months, with the destination finder first finding all the jobs for Sims who need them, and then the pathfinder calculating the necessary paths. The reason that the destination finder must run first, and not in parallel with the pathfinder, is simply for efficiency reasons. As will become clear as this guide progresses, both of these functions need a large amount of memory to run. The minimum system requirements for SC4 are a Pentium III 500 with 128 MB of memory. It is difficult enough running this game at all in such an environment. If the destination finder and the pathfinder ran in parallel, the amount of memory required would be greatly increased, and a lot of paging would result on minimal systems, resulting in the game's running several times slower, essentially becoming unplayable for all but the smallest cities. For this reason, and because running the two functions in parallel doesn't gain anything, we can assume that they are run sequentially. The Destination Finder In every traffic simulator run, the destination finder systematically goes through all the residences in the city and sees which Sims need new jobs. RippleJet discovered the default movement pattern of the destination finder: Quote from: RippleJet on December 13, 2009, 03:03:56 AM How the destination finder decides that a Sim needs a new job is somewhat more complex. The Prima Guide claims that as of Rush Hour, "the Sims hold their jobs until something forces them to find another." But extensive testing in mature cities seems to show a lot more job changing than this statement would imply. Further research is needed here. What is known at this point is that there are many different properties that can affect the destination finder's choice of a job for a Sim. Depending on the values of these properties, the destination finder may decide that no suitable job exists for a particular Sim, and the pathfinder won't even be run for that Sim. It has become clear that the destination finder has been tuned aggressively by Maxis in ways that we cannot access in order to minimize how much the pathfinder must run, since finding paths is one of the most expensive operations (in terms of CPU time and memory) in SC4. The destination finder will make an educated guess as to whether a path is even possible between a Sim's residence and a prospective job. Presumably, if it decides that such a path is not possible, it will look for other open jobs. Ideally, it would check all open jobs until it finds one it thinks would work, but at this point, we don't know if it does that, or if there's a limit on the number of jobs it checks. We do know that there are various properties that influence where it looks for jobs, and those are discussed below. The destination finder also knows a little bit about how the pathfinder works, and uses this knowledge to help decide whether or not it thinks a job is reachable from a residence. In determining a more precise value for the perfect pathfinding heuristic, I found out something very interesting: In deciding whether a job is reachable from a residence with the current traffic simulator settings, the destination finder weighs the presence of subways very heavily, especially subways that go very near the residence, and presumably, those that go near the job as well. It's not just subways, though - any rail network will do, and highways will work almost as well. It's just easier to place a large network of subways than any other type of network, since they don't take up surface real estate. At first glance, this whole behavior seems very strange indeed. It seems even stranger when you discover that this holds true even when the traffic simulator uses perfect pathfinding, and even when Commute Trip Max Time is set to many times the amount required for a successful trip. Even in such circumstances, buildings can be abandoned due to commute time when perfectly good jobs are available in the city. But add a few subways in the right places, and abandonment disappears. To understand what's happening here, it's important to remember that in the original Maxis traffic simulator, Commute Trip Max Time is set to six minutes. And in the original Maxis simulator, using the subway speed of 150 kph, you can get from one corner of a large tile to the opposite corner in 3.28 minutes via subway. In other words, you can get from anywhere to anywhere else on a large tile via subway in the original Maxis simulator, and still have enough time left over to walk a little ways to and from the stations. I think this helps explain why the six minutes was originally chosen for Commute Trip Max Time. It also allows the destination finder to make a quick and dirty test. If there are enough subways around, and the subways go close enough to the businesses and residences, then with perfect pathfinding (or something close to it), the Sims can probably make it to such a job within six minutes, and the destination finder hands off the source/destination pair to the pathfinder. But without enough subways or other high-speed networks, they may not, and further tests have to be done. This only makes sense if we use the six minute figure. But this behavior persists even when Commute Trip Max Time is set much higher - even a hundred times as high. The only way I can think to explain this is that the six minute figure is hardwired into parts of the destination finder. There's another interesting implication here. Sims can be guaranteed to reach anywhere on a large tile only if perfect pathfinding is used. Without perfect pathfinding, the destination finder will preemptively discard many otherwise valid trips, as has been shown in the experiments mentioned above. This would tend to support the theory that the Maxis programmers originally intended that the traffic simulator be used with perfect pathfinding, and indeed used it themselves; it was likely only the constraints of having to run a Pentium III 500 with 128 MB of memory that resulted in perfect pathfinding being abandoned for the commercial product. This issue is discussed in more detail in the Appendix. The destination finder also uses a time limit in deciding what trips are feasible. Based on the various properties described below, if it thinks that calculating a valid path is going to take more than a certain amount of time, it declares that path as being invalid. In standard A* pathfinding (described below), values for the heuristic lower than the perfect value should still produce perfect paths; they just take longer. But in SC4, values lower than the perfect value can result in additional abandonment or downgrading. This is due to the time limit imposed by the destination finder. The properties that are known to affect the operation of the destination finder are as follows, in approximate order of importance. When optimum values for these properties have been through experimentation, these optimum values are noted after the property's description. Pathfinding Heuristic (a.k.a. Nearest Destination Attractiveness) Even before Rush Hour was released the7trumpets and many others recognized this as the most important property in the whole traffic simulator. And even back then, when Maxis was still talking to the SC4 community, they referred to this property by both of its names. Both aspects of this property come into play in the destination finder. The traffic simulator's pathfinder uses a modified version of the A* algorithm, which is described very well in Amit’s A* Pages. Basically, the number and complexity of the possible paths between Sims and their jobs grows exponentially with the size of a city. The A* algorithm is designed so that it will always find a path between its source and destination points if one exists. The pathfinding heuristic is a constant that determines how close to perfect these paths are; i.e., how close they are to the fastest possible path. In perfect pathfinding, the value of the pathfinding heuristic is such that the fastest possible path is always found. In SC4, this number has been experimentally determined to be approximately .005797. The behavior of A* is generally exponential, in that as the pathfinding heuristic approaches the perfect number, the time to compute paths rises exponentially. However, as the pathfinding heuristic gets close to the perfect number, the exponential behavior gradually decreases, and it costs less and less to approach perfection. Below the perfect number, the paths produced are still the fastest, but the time to compute them increases again. In Amit's words: That's how standard A* pathfinding works. However, in SC4, much of the destination finder has been designed to cripple the activities of the A* pathfinder for the sake of efficiency. Whereas the standard A* algorithm is designed to always find a valid path if one exists, regardless of the value of the pathfinding heuristic, in SC4 the probability of finding a valid path declines as the pathfinding heuristic moves away from its theoretically perfect value, which is approximately .005797. So while in standard A* pathfinding, the worst penalty for not using perfect pathfinding is having longer paths, in SC4 the worst penalty for not using perfect pathfinding is not finding valid paths at all. This is a big difference, and is where most of the "Abandonment due to commute time" comes from. Furthermore, if some residents of a building aren't able to find valid paths to jobs, but others are, the pathfinding failures of the unemployed residents is averaged in with the commute time of the employed residents. This can result in the commute time that is associated with the residence being designated "Long," which reduces the desirability of the residence. This can happen even when all the employed residents of the building have short commutes. It was mentioned above that in the traffic simulator, the Pathfinding Heuristic property is also known as Nearest Destination Attractiveness. The reasoning behind this is very simple. Although the distance a Sim can travel during a commute is theoretically limited only by the Commute Trip Max Time property, in practice the Pathfinding Heuristic plays a big part as well. The higher the Pathfinding Heuristic, the more likely it is that the Sims will not take the fastest path, and instead will take the most direct path. In other words, a higher Pathfinding Heuristic effectively reduces their range of travel. The destination finder takes this into account, as it figures that there's no point in setting a destination that the Sims can't reach, and the higher the Pathfinding Heuristic, the more the destination finder steers the Sims to nearer destinations. Unfortunately, the destination finder appears to be overly conservative in estimating the limiting effects of the Pathfinding Heuristic. The result is that the destination finder draws a line beyond which the Sims cannot go in their travels, based on the values of the Pathfinding Heuristic and the Commute Trip Max Time. This line has been observed by multiple people; for example, in this post by jplumbley: That is exactly what was happening. The destination finder figures that the pathfinder will never find a valid path to points beyond that line within the time available, so why spend the extra CPU time and memory letting the pathfinder try to solve what is probably a hopeless task? So the pathfinder never runs for those Sims for whom a destination cannot be found on their side of the line. This entire strategy accomplishes what it sets out to do - it gives a basic implementation of A* pathfinding while limiting the amount of CPU time and memory spent in these expensive calculations. But it does so at great cost. Instead of having a pathfinder that always finds valid paths, we have one that finds valid paths most of the time, the exact percentage depending on the value of the Pathfinding Heuristic, Commute Trip Max Time, how close zones are, and the size of the cities in question. Fortunately, if we use perfect pathfinding and follow the guidelines about using high-speed networks, realistic cities of almost any size (along with many not so realistic ones) can be built. What about traffic simulators that don't use perfect pathfinding? If zones are intermixed closely, than large cities can still be built quite successfully. For smaller cities, the complexity of paths declines exponentially, and the traffic simulators all begin to behave quite similarly in terms of pathfinding. But there is no downside at all to using perfect pathfinding; even the supposed performance disadvantage is minimal at best. For example, SC4 using the Simulator Z v2.2 has been measured to run from 0% to 10% slower than SC4 using the standard Maxis simulator - not a big difference considering the difference in results. This advantage of perfect pathfinding was known to the SC4 community even before the release of the Rush Hour pack; this is documented in the Appendix below. Optimum value: .005797 As this guide is too big for a single post, it will be continued in succeeding posts.
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The NAM Unified Traffic Simulator The NAM Unified Traffic Simulator (or the NAM Simulator, for short) is a traffic simulator that is derived from the original Maxis traffic simulator, but is also built upon the knowledge gained from all previous NAM traffic simulators, including work by the7trumpets, Tropod, jplumbley, Mott, and z. It uses the Simulator Z core; what makes it a unified simulator is that it makes available to the player all the main features found in all previous traffic simulators. What makes this possible is the Traffic Simulator Configuration Tool (TSCT), which can be used to customize the NAM Simulator in any of these ways, and it also allows the ordinary player to safely customize the traffic simulator in ways that were not possible previously. The TSCT is available as an option in the NAM installer when the option "I want to build a custom simulator" is chosen; it is also available as part of the NAM Traffic Subsystem. Since the NAM Simulator evolved from Simulator Z, many of the features listed here for the NAM Simulator were also present in various versions of Simulator Z. However, many of these versions were never released together with the NAM, and so most people will be seeing the features they contained for the first time here. One of the main areas of the work on the NAM Simulator involved increasing the efficiency of the pathfinder to close to its theoretical maximum (it uses the "perfect pathfinding" settings), while also increasing the Sims' maximum commute time to be closer to real-world conditions. This allows a smoother distribution of traffic throughout the city, with typically less congestion. At the same time, the congestion that does exist is less likely to lead to abandonment due to commute time; Sims know that they occasionally have to sit through traffic jams, and are a bit more patient. Better pathfinding also means that Sims act much smarter about finding jobs and routes to them; this also results in less abandonment due to commute time. As in the real world, zones can be farther apart without causing problems; this is especially helpful when building existing cities to scale. Finally, running the pathfinder with near-optimum settings allows the simulator to run up to several times as fast as previous simulators. The second major area of work on the NAM Simulator involved a more flexible distribution of traffic among the various travel types. In combination with the pathfinder upgrading, this allows buses to be counted toward traffic and congestion, just like all other vehicles. This is a significant change from all previous simulators, and it's an important point to remember when planning your transportation infrastructure. More flexible distribution of traffic also means that the NAM Simulator is much more dynamic about allowing Sims to choose their transportation. In cities with excellent highways and road capacity, car usage has been measured at over six times that of previous simulators. Yet for cities with less extensive road networks and reasonable mass transit, car usage is actually less than in previous simulators. Other changes in the NAM Simulator include the following: More realistic subway costs. Subways in SC4 are tremendously underpriced compared to the real world. The improvements to the pathfinder have made huge networks of subways less necessary, so the monthly cost for subway tiles has been multiplied by six to add more realism. More realistic air pollution due to traffic. Until now, the amount of air pollution emitted by traffic has been unchanged from the original game, where it was based on cities that had far less traffic capacity than that used by any of the current simulators. To keep the amount of air pollution emitted by traffic to a more realistic amount, the proportion of traffic air pollution to actual traffic has been lowered in the NAM Simulator. This lower proportion is linked to the Clean Air Act, so it is in effect only when the Clean Air Act is enabled. More accurate numbers for the Commute Time Graph. Due to a bug in the game, it is impossible to get accurate Commute Time Graph numbers for all situations. However, the NAM Simulator has adjusted the scaling of this graph to provide reasonably accurate numbers for most situations. Improved intersection effects. Despite the appearance of stoplights at intersections, Sims don't actually stop; they don't even slow down unless congestion is present around the intersection. the NAM Simulator provides much more congestion around heavily-travelled intersections, thereby doing a better job of simulating stop lights and stop signs. Greater monorail and high speed rail usage. Due to a bug in the game, monorail and HSR usage is generally less than it should be, sometimes by quite a bit. the NAM Simulator compensates for this bug by raising monorail usage to appropriate levels Monorails and HSR have been fixed to contribute to and be affected by traffic congestion, just like all other vehicles. The following features are new as of the May 2010 NAM: Greater highway usage. The traffic simulator has been tuned so that Sims use highways much more than ever before. This usage still tends to fall short of real world usage, though, due to the structure of the game. The amount of rapid transit available in a city will also have a big effect on highway usage. All mass transit speeds have been recalibrated to provide a more realistic simulation. Improved customer levels for businesses. Capacities and speeds of one-way roads have been raised to duplicate the real-world advantage of these roads. Street capacities have been raised so that they reflect the capacities implied by their speed limits. There are Park and Ride versions of the NAM Simulator; these can be enabled with the Traffic Simulator Customization Tool, mentioned above. Park and Ride changes the game slightly so that cars cannot reach their destination directly. Instead, those Sims who prefer to drive must park near some sort of mass transit station, and then take mass transit to the stop closest to their workplace. From here, they must walk the rest of the way. For this to work well, you need to have an extensive mass transit system. You also need to build parking lots and/or parking garages near key mass transit stops; generally the best places are at the edges of your residential areas that are closest to your jobs. Or you could just build parking facilities near the Sims' jobs (the ones that come with buildings generally don't count), but this really defeats the main purpose of Park and Ride. If you choose the Park and Ride version of a simulator, but don't build extra parking facilities, your game will not work very well at all. I have found RalphaelNinja's Ninja Boulevard Station and Ninja Boulevard Kiosk to be very useful in general, and particularly useful for Park and Ride, as they both contain large underground garages. I have enclosed modified lot files for both of these stations at the end of this post; the modifications bring the monthly cost down to be more in line with similar stations, and they also double the capacity, bringing them more in line with RTMT (and making them especially useful for Park and Ride). Since the exquisite design of these stations must have cost a lot of money, I left the plop cost alone. Also, since I have enclosed only the lot files, if you don't have these stations already, you'll need to download them from the above links. What are the different versions of the NAM Simulator, and how are they used? The NAM Simulator comes in five versions - Classic, Low, Medium, High, and Ultra. The name of the version refers to the network capacities in the simulator. The following is a list of the network capacities for each version of the simulator; all capacities are per tile: Which simulator version is appropriate for a particular city depends primarily on two things: the population of the city, and the amount of rapid transit (rails) available. Less capacity is needed for lower population cities, but less capacity is also required for cities with a lot of rapid transit. For example, a city of two million Sims has been run quite successfully using the Low capacity version of the NAM Simulator, but it had an extremely extensive subway system. So pick a simulator version based on these two factors; if it doesn't seem the right capacity, you can always switch it out for a different capacity version. Experience has shown that in large cities, the effects of such a switch may take up to five years to fully manifest. You can tell when things have stabilized by looking at the Traffic Volume Graph in the following way: First, let the game run until there is a sudden shift in traffic patterns. Sometimes, this may take over a year. Then run the game until you go at least a full year without any sudden change in traffic patterns. At that point, the transition to the new capacity simulator is complete. Installing the NAM Simulator The NAM Simulator is installed during the NAM installation. If you've already installed the NAM, you can reinstall the simulator by installing and running the NAM Traffic Subsystem. Traffic Volume View and Other New Data Views The Traffic Volume View included with the NAM as of the June, 2009 version offers a number of improvements to the one included with the game. Rather than the seven shades of blue in the original, this version uses the full spectrum of color, including approximately 48 distinct color shades. The maximum volume shown for each travel type has been increased from a flat 1200 for all types in the original Traffic Volume View to a value which is 300% of the capacity of the underlying network for the selected travel type. (Since only one commute period is shown at a time, this is one half of the standard network capacity, which is calculated for a full day.) The legend has been increased from five to nine entries, and each color in the legend is followed by the percentage of the underlying network capacity that that color represents, as well as the actual number of Sims represented by that percentage. When a travel type may have more than one underlying network (e.g., cars may travel on streets, roads, or highways), a subtext below the legend indicates which network is being referenced in the display. The colors in the display have been arranged so that they are more concentrated at lower levels, in order to give finer granularity at lower volumes. Between volumes of 0% and 10%, colors change about every 1.5%. Between 10% and 130%, colors change about ever 5%. And between 130% and 300%, colors change about every 10%. Please note that while every attempt has been made to attain the greatest accuracy possible, all numbers are somewhat approximate. The numbers following each color in the legend refer to the approximate beginning of the range of that particular color. You may notice that starting at 100%, the colors closely follow those in the Traffic Congestion View. However, it is important to keep in mind the difference between the Traffic Congestion View and the Traffic Volume View. The Congestion View is compiled from an entire day's travel statistics, while the Volume View refers to only a single commute period. Therefore, yellow in a single volume view does not necessarily indicate congestion, and blue or green in a single volume view does not necessarily indicate lack of congestion. An experienced player may be able to look at both commute periods of certain volume views and get a good idea of congestion, but it is necessary to be careful here. Finally, most transit station types light up in all volume views. This does not indicate anything about usage; it is simply so you can identify them easily. Certain types of transit stations do not light up because of the way they were designed. The Traffic Volume View also includes a new Subway View. The new Subway View acts in most ways like the normal underground Subway View, which is entered by selecting the Subway Tool when you want to build or demolish subways. However, it has included in it the volume display feature of the Traffic Volume View, which allows you to see the usage of your subways as you are building (or demolishing) them. Like the rest of the Traffic Volume View, this view shows the volume of traffic in each subway line visible in the main map, as well as in all subway lines in the minimap. The last feature included in the Traffic Volume View is a new Subway Building View, which is entered whenever you select a subway station to build. It differs from the standard Subway Building View in that no buildings other than subway stations are displayed; zones are displayed wherever possible; and like the Subway View, the volume of traffic in each subway line visible in the main map, as well as in all subway lines in the minimap. In addition, zones and transit station locations are shown in the minimap. Finally, most transit station types light up in all volume views. This does not indicate anything about usage; it is simply so you can identify them easily. Certain types of transit stations do not light up because of the way they were designed. A new Zones view is also included with the NAM. The new Zones view is identical to the Subway Building View, except that subway volume levels are not displayed. The new Zones view is currently optional (unlike the other data views described above, so you must select it during the NAM installation if you want to have it installed. It is strongly recommended that you use the DatPacker if you have a substantial number of plugins. This will not only speed up the loading of your game, but it will also great speed up switching back to the normal view from both the Subway Building View and the Zones View. Patch for RTMT Users If you are using RTMT, it is highly recommended that you install the latest patch, which is especially important for the NAM Simulator users. You can find the patch here. Stations originally created by @RalphaelNinja with modified reduced costs and doubled capacities: Modified Ninja Boulevard Stations.zip
