Railroad simulation

A train simulator (also railroad simulator or railway simulator) is a computer based simulation of rail transport operations. They are generally large complicated software packages modeling a 3D virtual reality world implemented both as commercial trainers, and consumer computer game software with 'play modes' which lets the user interact by stepping inside the virtual world. Because of the near view modeling, often at speed, train simulator software is generally far more complicated and difficult software to write and implement than flight simulator programs.

While commercial trainers on mini-computer systems had a longer history, the first two mass-market English 'computer game' railway simulators, MSTS and Trainz, arrived within a few months of one another in 2001 and could run (poorly) on Intel 80386 microprocessor based systems. Some, like the first wide-market release, Microsoft Train Simulator (MSTS), are written and modeled for the user mainly interested in driving. Others, like MSTS's principle rival, Trainz, were aimed initially primarily at the rail enthusiast-hobbyist markets, supporting features making it possible to build a virtual railroad of one's dreams. Accordingly, for four years Trainz releases bundled a free copy of gmax digital model building software on each CDROM, hosted an asset swap website (Trainz Exchange, later the Trainz Download Station), encouraged user participation and dialog with an active forum, and took pains to publish in-depth how-to model guidelines and specifications with its releases.

Several other later challengers as well as Trainz (with a series of upgrades) soon matched or eclipsed MSTS's driving experiences one way or another. Railsim, actually a successor using the MSTS game engine upped the challenge to the aging MSTS by adding much improved graphics, so Trainz did as well, but also added interactive industries and dynamic driving features such as product loading and unloading, load-sensitive physics modeling affecting driving and operating and user interface changes to improve User eXperiences (UX), such as a free camera mode allowing roaming away from the train cars, free and clear of the Train being operated-while still controlling it. This latter makes particular sense given the dearth of an assistant on a walkie-talky while operating a train during coupling operations or other position sensitive tasks such as loading and unloading. Railsim and a couple of others came and went out of business, and Railsim was reorganized as Rail Simulator with the software company that wrote MSTS as its core, while MSTS aged and never did get upgraded as Microsoft had once begun and announced. In the last few years, Rail Simulator has changed its name to Train Simulator 2016.

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