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 Customization 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 Sim City 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-traveled 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.
- 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.
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:
Network Classic Low Medium High Ultra
Street 100 1500 2400 3600 7200
Road 1200 2400 4000 6000 12,000
Avenue 1400 2400 4000 6000 12,000
One-way Road 1800 3600 6000 9000 18,000
Rail 3000 10,000 16,000 30,000 65,200
Subway 3000 10,000 16,000 30,000 65,200
Elevated Rail 3000 10,000 16,000 30,000 65,200
Monorail 3000 10,000 16,000 30,000 65,200
RHW 2700 6000 10,000 15,000 30,000
Highway 4000 9000 15,000 22,500 45,000
Ground Highway 4000 9000 15,000 22,500 45,000
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 originalTraffic 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 theTraffic 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 folume 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.
Edited by z1, 02 January 2013 - 03:24 AM.