Author Topic: OXCE (OpenXcom Extended) main thread  (Read 446248 times)

Offline Yankes

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1125 on: June 29, 2022, 03:06:54 am »
My best guess is that... when you moved the running cost multiplication from Pathfinding::previewPath() to Pathfinding::getTUCost(), it somehow caused the bug. But I can't confirm this or tell why.
After fixing this bug answer that algorithm correct find "fastest" path, trick was that cost had weight based of distance to target that for running or when your reduce cost of move it become screw too much and will miss real fastest path.

Offline Delian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1126 on: June 29, 2022, 10:52:12 am »
Ok, let me test...

...the 1st and 3rd cases were fixed. The 2nd case (with 15 TU difference) still fails to find fastest path.

Offline Yankes

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1127 on: June 29, 2022, 11:50:12 am »
This probably stay as is, if straight path exist then it will be choose even if cost more, this is manly for control, when you want move unit precisely.

As this is part of UIX this will require Meridian blessing to change it.

Offline Delian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1128 on: June 29, 2022, 01:25:07 pm »
As this is part of UIX this will require Meridian blessing to change it.

I've attached another screenshot. Can you confirm that the path that's used in this screenshot uses Bresenham? I think here it uses A*...

Offline Yankes

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1129 on: June 29, 2022, 01:33:10 pm »
Yes, it should use it there. You can test it by move starting point that it could not make "line path" then it will choose more effective one.

Offline Delian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1130 on: June 29, 2022, 02:47:37 pm »
Ok, yeah, it does use Bresenham.

But you know, Bresenham isn't used for "precision and control". It's used mainly in cases of diagonal flying, so that you get a zig-zag path instead of two long lines (one straight and one diagonal). If I wanted precise control, then I'd just move a unit 1-2 tiles at a time. But yeah, when multiple optimal paths exist, Bresenham line is preferred. But if Bresenham is not the optimal path, then it should not be used.

It's kinda funny because the code in Bresenham is like.. if (... tuCost == lastTUCost ...), basically, to check if bresenham is optimal path, the function only checks if there were any changes in movement cost from one tile to the next, so if you're running on expensive terrain (tall grass / wheat fields) the whole time, it won't notice any changes. But if it detects changes in the cost, then Bresenham will say "I'm not optimal path, don't use me". I've attached a screenshot where you can see that a straight line exists, but because there's one cheaper tile in between, it detects this change in cost and then A* is used instead.

Anyway, yeah, since that's an OXC bug, it's up to Meridian to decide what to do with it.

Online Meridian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1131 on: July 04, 2022, 07:27:44 pm »
I think you could've done the same for energy
const auto energyCost = (cost.EnergyPercent - 1 + costDiv / 2) / costDiv;

For now Meridian said that for now leave it as is.

I have tested the compatibility with this earlier TFTD-compatibility fix: https://github.com/MeridianOXC/OpenXcom/commit/ff3ac8d8ada2a838bf525df2caf2dab78adac9f6

As far as I can say, it works well.

So, from my side, we can change also the Energy formula to be the same as the new TU formula.

Offline Yankes

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1132 on: July 04, 2022, 07:43:17 pm »
Ok

Online Meridian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1133 on: July 05, 2022, 04:15:32 pm »
Anyway, yeah, since that's an OXC bug, it's up to Meridian to decide what to do with it.

There is no right or wrong answer here, so I'll just share my opinion.

The original game doesn't find the optimal path either.
Without any hard evidence, I'd guess that it was a deliberate design decision... to provide players with more natural paths instead of the cheaper ones (at all costs).
(Optimal path algorithms were already well known in the 1990's and they were not too memory- or cpu-intensive.)

It's kinda funny because the code in Bresenham is like.. if (... tuCost == lastTUCost ...), basically, to check if bresenham is optimal path, the function only checks if there were any changes in movement cost from one tile to the next, so if you're running on expensive terrain (tall grass / wheat fields) the whole time, it won't notice any changes. But if it detects changes in the cost, then Bresenham will say "I'm not optimal path, don't use me". I've attached a screenshot where you can see that a straight line exists, but because there's one cheaper tile in between, it detects this change in cost and then A* is used instead.

This was definitely a deliberate decision from OXC devs.

OXC changed (I am intentionally not using the word "improved") the pathfinding algorithm to produce more TU-optimal paths.
But in a decent number of cases, TU-optimal paths differ from natural paths, which irritates a lot of people (including myself), and so the compromise you described above was made to produce more natural paths again (although not as many as the original game).

One example for all: when you start your very first mission and tell your very first rookie to go down the Skyranger ramp:
1/ the original game will take the straight natural path (as everybody would expect I hope)
2/ openxcom will take a funny, unrealistic path involving a jump down from the ramp... that both looks bad and in reality should cost a lot more than just walking down the ramp

(Let me just repeat that... the very first command you issue as an xcom commander on a battlefield, is executed differently in openxcom than most of us would expect. I can only guess how much this bothered OXC devs and how painful the compromise must have been. I definitely don't envy them.)

I personally prefer natural paths, which give me more precision-control as Yankes said, without too much hassle.
And they look better too.
That's why if I could choose how to fix this issue, I'd revert back to the original algorithms from 1994 and not use openxcom algorithms.

But breaking compatibility with openxcom would cause me more trouble (from all the nitpickers around) than it's worth... so at the end, I will compromise too and not do anything.

Offline Delian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1134 on: July 05, 2022, 10:46:23 pm »
Thank you for the explanation. It's ok then.

The bug in bresenham can be worked around by players because it's easy to see if you're walking on expensive terrain or not. So for people (myself included) who prefer TU-optimal paths over straight paths, it shouldn't be much of an issue.

As far as the original pathfinding goes, I think back then pathfinding algorithms weren't as good as they are today, and that was the main reason for the straight paths. Perhaps OXC devs saw this, and that's why they chose to use an improved one instead. I can't say what is or isn't expected, or what l looks good/bad, but in reality, walking down a ramp should cost less than walking up the ramp hehe~
« Last Edit: July 05, 2022, 11:06:37 pm by Delian »

Offline Valerra

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1135 on: July 06, 2022, 06:12:06 am »
I got this error on loading OXCE 7.53
"Error for 'ALIEN_PSI_WEAPON': Wrong index 36 for sound set BATTLE.CAT"

and many more similar errors in log file.

What's wrong?

maybe the reason is i don't have any sound device. OXCE 7.3 version is Ok

Online Meridian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1136 on: July 07, 2022, 12:16:48 pm »
Hi Meridian,

I hope I'm posting this in the right place -- I am trying to cross compile both OXCE and FtA from Linux using your instructions, but it seems I am probably doing something wrong. Can you point me in the right direction, or by any chance, does it fail for you in the same way currently? To clarify, I've tried this for both OXCE and FtA and neither are successful.

This is what is, I think, the relevant bit from the logs (I've also attached the full build logs for both OXCE/FtA below):

Hi,

I don't have this setup locally anymore, I'd need to install everything again...

But we have this setup on the build farm (maintained by Stoddard) running fine for some years now.

The build farm is also building FtA, most likely using the same setup (https://lxnt.wtf/oxem/#/FTA), but Stoddard or Finnik should confirm.

Online Meridian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1137 on: July 07, 2022, 12:18:07 pm »
I got this error on loading OXCE 7.53
"Error for 'ALIEN_PSI_WEAPON': Wrong index 36 for sound set BATTLE.CAT"
and many more similar errors in log file.
What's wrong?
maybe the reason is i don't have any sound device. OXCE 7.3 version is Ok

Should be fixed in v7.5.19

See also: https://openxcom.org/forum/index.php/topic,10541.msg147434.html#msg147434

Offline Rangerh

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1138 on: July 08, 2022, 08:32:58 pm »
A question about the "sickBayAbsoluteBonus" and "sickBayRelativeBonus"

On a game with the 40k/Rosigma  i have some troops with extreme recovery time a bit too often (that's because 40k/Rosigma troops have a lot of HP so they endure a lot more wounds ingame).
So i checked https://www.ufopaedia.org/index.php/Ruleset_Reference_Nightly_(OpenXcom)#Base_Facilities

Found that those sickbay could be interesting to work around the problem. So i added

sickBayAbsoluteBonus: 0.0
sickBayRelativeBonus: 10.0

To the STR_ACCESS_LIFT entry (that is found in terrain_40k.rul file from the 40k mod folder) , as it's the basic facility that every underground base will have from the start.
According to the ufopedia website entry , this should means the building provide a healing bonus of 10% by day, so it should mean my troops would all be healed in a maximum of 10 days.

But after more testing, it is not the case, the recovery time is going at a normal rate (i mean the same as if i had not added the sickbay entries)
To test more, i increased sickBayRelativeBonus: 10.0 to  50.0 , so any wounded unit should be healed at max in 2 days if i understand the ufopedia website explaination.
But again after testing ingame, i see the soldiers only recovering at a normal rate (after several days the high wounded still have a high recovery time).

Any idea at what am i doing wrong ?

« Last Edit: July 08, 2022, 08:36:31 pm by Rangerh »

Online Meridian

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Re: OXCE (OpenXcom Extended) main thread
« Reply #1139 on: July 09, 2022, 02:09:47 am »
it works fine for me... you have a syntax error (or equivalent) somewhere