If they're both manually operated then they're going to need to carry a huge amount of rock to justify the overhead of operating them, let alone the overhead of building them and their tracks. (sidenote, I think some mines used grooves carved in the floor which might work better)
Moving water or magma around might possibly be another use? If you can move large amounts at once it would help stop evaporation problems, and it would be worth the overhead compared to building a pump network in some cases.
I am looking forward to sections of the fortress moving though, if only for a "Transformers: Fortresses in Disguise" thread.
Yes, I have no doubt that the first thing everyone will do upon the instant a version of DF with moving fortress parts is released is to build a horde of giant spider walkers that vomit magma at attacking goblins. I look forward to the arms race. (I also wonder if "improved sieging" will include goblin spider walkers with magma, just as part of that arms race - SURPRISE, SUCKERS! Remember that child the goblins kidnapped 4 years ago? Now goblins have the secrets of magma-spewing spider-walkers, too!)
Anyway, I think that stone tracks would be by far the most preferred method of running a minecart, and could probably just be designated to be carved into the floor as you go. Maybe it would be slower than a metal track, but it's a world less annoying than actually using a metal bar to extend a minecart track to the next set of iron ore that you are going to convert into the steel that you will only use extending the mine cart tracks. Even if one steel bar made 10 tiles of track, you're asking a lot, and I expect it would only be really useful in the truly important areas where additional speed in movement would be worth almost any material price.
Shipping magma by minecart seems both crazy and dwarfy, if not quite as dwarfy as the utterly insane magma piston. I can't wait for mechanics that include making a minecart going down a ramp speed the cart up, and make turns along the track "slosh out" some of the magma onto unsuspecting dwarves, or runaway minecarts create Frogger-style !!Fun!! for your miners or maybe some goblins. OK, so maybe not a big utility to the average player, but it is some sadistic fun. Plus, I still have fond memories of designing roller coasters in some old theme park simulator games, where you had to keep the actual physics of how fast your roller coaster was going in mind. That seems like the sort of fun and/or Fun that DF is made for.
... with all that said, I think we've sailed waaaay off topic in the past couple pages. Weren't we talking about ways to optimize pathfinding before?
Or is there nothing left to talk about regarding how to make gathering as many items as possible into the most efficient task processor-wise possible?
Darn my lengthy posts and tendency to get ninjad for it...
Wow, nice... grooves could make the whole shebang work.
Yeah, I think the best way to handle carts would be just designating mining tracks as you carve through the rock, and designating certain "stops" by hand if need be, although just having the dwarves automatically know where best to place their minecart would be the ideal solution, if one that might take some fancy (if fortunately infrequent) pathfinding decisions.