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[0x517A5D]

Dwarf Fortress uses a modified A* search algorithm for pathfinding.

Right, the question was how often it uses the modified A* algorithm, though. Once every tick? Or once at the start of the path and then not again unless hitting an obstacle or predicting an obstacle etc.

Once at the start of the move-to-place job.  You can see this by locking a door that a dwarf needs to walk through, and noting how the dwarf will still path right up to that door, then flash a question mark for a bit.

There is also some world-level caching of valid routes — DFHack exposes it as path_tag and path_cost in each map_block, and in world.pathfinder.boundary_heap.

Also DFHack has a script that shows a minecart's current cached path, and another that shows a creature's current cached path.

[GavJ]

Oh yeah! The question mark. Of course...

[Orange Wizard]

Not sure if anyone's heard, but according to the devlog Toady's done some optimising and he's doubled the FPS of his test save.

[malvado]

Aye I noticed his update.
In my case that means I could probably go from 30fps to 60fps currently.
More optimizations will be needed to get the game back to the same numbers I had in 34.x , but it's definitely a good update.

[StagnantSoul]

I generally get to 10-20 after a few years, so 20-40 would be a god send.

[Kryxx]

With what type of processor?  also what embark size?  I'm curious as the my fort grows I'd like a rough gauge.

[Robsoie]

I hope those optimisations will have some impact in adventure mode too, some sites (especially goblin ones) are very or sometime just unplayable slow in current versions

[Z1000000m]

With what type of processor?  also what embark size?  I'm curious as the my fort grows I'd like a rough gauge.

It probably went from 1 fps to 2...

[MDFification]

With what type of processor?  also what embark size?  I'm curious as the my fort grows I'd like a rough gauge.

He didn't say... but he did confirm that the optimizations will affect any fort, and specifically helps forts with larger populations. So it should be a fairly universal boost.
There's a lot of negativity in this thread I notice. I feel like some people are regretting playing on a toaster. (my laptop is 4 years old, in case I seem like I'm being an entitled jerk)

[Kryxx]

Part of the issue is playing on a laptop.   Some of the early I-5's are not true quad cores.  It's a duo core each with hyper threading.  So you have to watch it.   

My laptop is this way, thus your not gaining that much of an advantage. But I don't play any games on my laptop.  It's for sitting out on the back porch watching the dogs and horses and surfing the net.

Then there are the heat issues with laptops in which many of them downclock themselves as they get hotter.   

I have an I-5 -3470(S).  Which is a 3.2ghz with a 3.6 turbo if it needs it, but  I rarely see the processor get over 50% even when saving or running with 60 dwarves (my max so far). Fps is still over 100 at that point.   I've been running 5x5 embarks. 

I was trying to gauge what people with 30-60fps are running for processors to understand where my limitation will be.   

Would be awesome to write an app to push the math co-processing over to the GPU since DF doesn't use it.  Would boost performance greatly.

[Streeter]

Would be awesome to write an app to push the math co-processing over to the GPU since DF doesn't use it.  Would boost performance greatly.

Oh most definitely. I keep seeing people pestering Toady with suggestions along the lines of "MOAR CORES". Do these people even realise that concurrency is difficult and bug-prone, and at times not worth the effort? I'll answer my own question: No, they don't. It's the first suggestion for improving perf that you'll hear from non-devs.


Stream processing, on the other hand? That would be a huge boon. Similarly difficult, but much more worth the effort than using a second thread. Many physics calculations would simply fly, and world-gen could become a breeze. I'm guessing that pathfinding would also work well for GPGPU (it's just a search over sparse graph data structures, right?). Though it would take a large change in the algorithm used, I'd imagine.

That said, keep in mind we're still in alpha. Don't expect Toady to rip out code and experiment with stuff like this anytime soon. I don't know how much things like water dynamics/temperature/pathing etc. rely on ticks in the main loop.

[rhoxa]

FPS has been the biggest issue for me so far.  I've stopped playing three forts now, all sometime around 2-3 years, because my FPS struggles to get above 25.  I'm using an i7 2600k at 4.5GHz, 8GB of RAM, SSD, GTX580.  Embarking 4x4 or 3x3.  I set up traffic areas, I blocked off the caverns, I tried turning off weather, there is no waterfall, I used HFhack to clean everything, and I'm still having poor FPS.  My map size is usually medium and history is medium too.  New forts stay at 100 then decrease SHARPLY when I hit that 2-3 year range.  Once I fixed it temporarily when I found a dwarf stuck in a tree, and another time by just closing the caverns off with locked doors, but it always manages to keep getting lower.

I didn't get a chance to try the newest build yet, but I will report back when I do.  Fingers crossed.

[NullForceOmega]

What speed is your RAM and what speed of RAM is your MoBo designed for?  I run forts on an i5 at 2.8GHz, with 8GB as well and I have NEVER had FPS that low, even over 18 in-game years, and I run forts at full industry on 3x3-5x5 embarks.  I don't use burrows, traffic designations, I dig out entire z's for materials, create tens of thousands of items and I don't drop below 60 FPS EVER.

[GavJ]

What speed is your RAM and what speed of RAM is your MoBo designed for?  I run forts on an i5 at 2.8GHz, with 8GB as well and I have NEVER had FPS that low, even over 18 in-game years, and I run forts at full industry on 3x3-5x5 embarks.  I don't use burrows, traffic designations, I dig out entire z's for materials, create tens of thousands of items and I don't drop below 60 FPS EVER.

Youve run 18 year forts in 40.xx? Keep in mind it could be a new issue, if you're referring to forts in 34.xx
I've never gotten anything close to his FPS either with a similar computer, but I haven't yet gotten around to playing a whole 3 year fort with the new version.

[NullForceOmega]

I've gotten to nine years in 40. so far, but my FPS holds very steady between 80 and 100 in those forts.