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[Untelligent]

Even Baughn doesn't have the whole source code, just some of the rendering and interface code.

If there's anyone with access to the game's inner workings aside from Toady, it would be Threetoe, and I haven't seen anything yet that would imply he can do any programming.

[lordnincompoop]

Nah. He's just a good writer and creative thinker.

[Rose]

oh, by the way

with the i7, you can disable hyperthreading yo instantly double the single threaded performance.

you can also disable some of the cores to give you better overclocking, if you are brave.

[Capntastic]

Threetoe used to help out on a lot of Toady's earlier games, way back in the day, and has said before if he had more time he'd begin programming more for fun.

[G-Flex]

If it helps any, IIRC he uses Manhattan distance and lots of bitshifts.

I don't know about distance calculations, but for certain calculations (particular time spent walking from tile to tile), diagonals are accounted for properly, not Manhattan-style.

[KillHour]

If it helps any, IIRC he uses Manhattan distance and lots of bitshifts.

I don't know about distance calculations, but for certain calculations (particular time spent walking from tile to tile), diagonals are accounted for properly, not Manhattan-style.

Pathfinding currently uses A*.

[Encased in burning magma]

If it helps any, IIRC he uses Manhattan distance and lots of bitshifts.

I don't know about distance calculations, but for certain calculations (particular time spent walking from tile to tile), diagonals are accounted for properly, not Manhattan-style.

Pathfinding currently uses A*.

The question is about the heuristic he uses...

[helf]

oh, by the way

with the i7, you can disable hyperthreading yo instantly double the single threaded performance.

you can also disable some of the cores to give you better overclocking, if you are brave.

uh, no? That is just plain incorrect. To put it simply, Hyper-threading keeps the CPU busy while threads stall out waiting for memory. Edumacate yourself some before responding to posts and perpetuating incorrect information - http://en.wikipedia.org/wiki/Hyper-threading

Also, its "Bloomfield", not Bluefeild

[Fayrik]

To put it simply, Hyper-threading keeps the CPU busy while threads stall out waiting for memory.

There's your problem. If a program stalls for just a short while, and then your CPU drops it and finds a new task, you have to wait for the program to be reinstated with CPU time.
For most tasks, this would mean less dropped Processor time, but in a case like Dwarf Fortress where we're not looking at other programs running along side it, it's gunna hinder it more than help it.
But, since I don't work for intel, I'm hardly in a position to make heads or tails of their--Uhh, stuff.

But, as a programmer, I can say without a doubt, being able to utilize multi-core processing relies entirely on the logic of the intended use, and not on the program, or programmer.
Simply put: If the program has to do things in a liniar order.. Like many programs do- (Hello world would be probably the top of the list, due to it's outstanding simplicity. Dwarf Fortress however, is most certainly on the list though.)- Then, even if you do come up with a long winded way of making the program multi-threaded, it's not going to see a fantastic process time relief.

Trying to clear my point up a bit here, to work out how easy it's going to be to make something multi-threaded, all you have to do is work out vaguely what the program is doing.
In the case of Dwarf Fortress, it runs in frames. So it's compiling each frame. Now, I'm not certain about how it works, but I'm pretty sure that everything within a frame is relies on other things in that very same frame, so while it's compiling said frame, it can't split tasks up and have other things like pathfinding go off on another thread, or else the pathfinding thread may not be ready by the time the rest of the frame is. Which would then mean the program has to stall to wait for that thread to finish...
I guess you could compare it to cars on a motorway. A van full of people is gunna be slower than three cars, but you can't use three cars if you end up designating a baby as a driver, in a different car to it's pairents.

I found on my lovely Phenom II X4 that actually, Dwarf Fortress runs best when given it's own independant thread. That way, while everything else is humming along nicely, Dwarf Fortress gets top priority on all it's processing needs. Like a bus lane.

[helf]

Yeah, I give DF an entire core to itself on my core2duo. Helps a *lot*.

[G-Flex]

In the case of Dwarf Fortress, it runs in frames. So it's compiling each frame. Now, I'm not certain about how it works, but I'm pretty sure that everything within a frame is relies on other things in that very same frame, so while it's compiling said frame, it can't split tasks up and have other things like pathfinding go off on another thread, or else the pathfinding thread may not be ready by the time the rest of the frame is.

I disagree in some ways. Plenty of things occurring within a frame are independent of each other, since they're essentially happening simultaneously. If ten dwarves have to pathfind in the same frame, they can do so independently of each other, since it's all simultaneous (in effect); there's no reason for them not to decide in parallel, since in game/logic terms they're doing so at the same time. That's just one example.

Fact is, lots of stuff goes on simultaneously during a frame, so it should be possible to parallelize those tasks significantly.

[Rose]

oh, by the way

with the i7, you can disable hyperthreading yo instantly double the single threaded performance.

you can also disable some of the cores to give you better overclocking, if you are brave.

uh, no? That is just plain incorrect. To put it simply, Hyper-threading keeps the CPU busy while threads stall out waiting for memory. Edumacate yourself some before responding to posts and perpetuating incorrect information - http://en.wikipedia.org/wiki/Hyper-threading

Also, its "Bloomfield", not Bluefeild

hey, I'm just going by experience.

same single threaded task, tried with hyperthreading on, and off, went faster with it off.

[helf]

well, do whatever works best for you then I disable HT on my netburst (p4) chips because it really does hurt performance a lot at times. I haven't noticed any downsides to i7 HT, tho.

[Dwarf]

I believe it was mentioned that DF, due to its code and very nature, was hard or even impossible to multi-thread?