RSP will include full dispatcher capabilities, prototypical signalling (that is fully customisable by country) and even allow online play. I noted with some interest recently on the Auran forums that some 'hard core' proto guys showed little interest in online play, yet oddly enough it's one of the most requested features of the many railroad companies we've been talking to. They see online as an opportunity to place drivers in a 'real traffic' environment (as they put it) and one that can only help improve driver safety. However, if you'd rather play standalone you certainly can.
The dispatcher system communicates to the main game (or games in a multiplayer environment) via TCPIP so yes, you've guessed it, the person acting as a dispatcher can be located anywhere in the world.
Driver AI is being fully overhauled in RSP and is being broken into two unique components. Drivers will no longer attempt to path plan, they just drive and follow signals as required. Therefore, the AI functions for drivers have actually been reduced in complexity from that present in TRS2004. Since RSP includes full route planning both the signalling system and dispatcher can refer to the planned routes and act accordingly. The other area that AI will now be operational is when you don't have a human acting as dispatcher. In this instance the AI will take over and resolve route conflicts within bounds set during the route-planning phase. This two-tier approach to AI will resolve most of the outstanding issues with AI.
The scripting system that is present in TSR2004 will be fully replaced in RSP with a C++ API based system and Auran will supply headers that provide access to most of the internal game functions. Programmers are going to have a ball with RSP and you're going to be able to some amazing things!
Those of you who like to populate your routes with more than just trains, for example ships and cars, will also be catered for. Like TRS2004, RSP supports invisible track and you'll be able to place boats and cars on it. However, unlike TRS2004, RSP boats will follow the track but not be attached to it. Instead, they float above it based on various parameters, two of which are 'sea state' and 'tide height'. Boats and cars can now have intersections, and traffic flow can move from one track to another.
The track system itself is also getting a major overhaul and is moving to a Bezier curve based system. Those of you who are familiar with products like Corel Draw will already know how this works. In essence when RSP is operating in 'simple' track laying mode it will appear just like TRS2004. However, hold down the 'Control' key and you'll have access to the Bezier handles that will allow fine control of the curve radius. Additionally, you'll have complete control over ballast types, track type, and best of all, super elevation. Because of all of these changes people who like Traction, Trams or Monorails are in for a real treat, as all of them are possible.
Physics is one area that will be very different indeed. RSP will allow programmers to write individual .DLL physics files for each and every loco. These individual loco physics programs can sit alongside the inbuilt (default physics) system and will happily coexist. In other words, if you have a certain steam loco that spins its wheels differently, or a rack and pinion rail motor that requires some unique handling, then you can load up a full physics system for each. All other locos that are present on the same route can continue to use the inbuilt system whilst the other locos use their own specific systems.
The final major area is of course sound. Every track type and bogie combination will be able to have their own unique sounds, and they will be calculated per axle and tied to rail based events.
(ahem)