(Naval) AI - Pathfinding question

Discussion about the game and its default mods.
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Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

(Naval) AI - Pathfinding question

Post by Ronald »

Morning OpenRA Sailors,
Recently i've been playing OpenRA (release-20200503 ) on the new Naval maps from this project created by Punsho
- viewtopic.php?f=82&t=21084

One of the nice naval maps is Isle of Man V9, which can be found over here:
- https://resource.openra.net/maps/33577/

Since I have purchased a more powerful computer, I decided to test OpenRA AI's a bit more. This is the setup for the test-game:
- Team1 : 1 Human player(Russia: Middle) + 2 naval AI (Ukraine: Top / Bottom)
- Team2 : 3 Naval AI (Any: Top, Middle, Bottom)
And the game kicked off nicely
openra_naval_ai_50.jpg
openra_naval_ai_50.jpg (367.48 KiB) Viewed 476 times
The coloured lines above represent the routes chosen by the various AI-players:
- Team 2 - (all AI's) were able to find and attack the Team1 bases.
- Team 1 - (top AI) was able to find its way to the enemies bases.
- Team 1 - (bottom AI) got somehow stuck.
Last edited by Ronald on Mon Aug 03, 2020 8:18 am, edited 4 times in total.

Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

Re: (Naval) AI - Pathfinding question

Post by Ronald »

openra_navalai_stuck_25.jpg
openra_navalai_stuck_25.jpg (271.58 KiB) Viewed 474 times
TEAM 1- (bottom AI) did not find its way to the enemy AI-'s bases.
It got (permanently) stuck halfway the bottom of this map. (inside the red area)

Now for my questions:
1 - Why and How can an AI-bot get stuck on a(ny) map?
- Is this an AI-Bot issue, which _can_ be caused by - for example - an AI-pathfinding-algorithm error(s) ?
- Is this a mapmaker issue, which _can_ be caused "bad map design" ?
- Option 3,4,n ?

2 - How can this be solved, In future OpenRa / Map releases?
- Must certain AI-bot / OpenRa Game_engine algorithms need to be redesigned , rewritten ?
- Do Mapmakers need to add in certain AI-friendly factors, when creating new maps ?
- Option 3,4,n ?

I'm looking forward to your answers and insights

Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

Re: (Naval) AI - Pathfinding question

Post by Ronald »

Follow-up to the postings above from yesterday.
openra_naval_ai_2_vrs_2.jpg
openra_naval_ai_2_vrs_2.jpg (364.71 KiB) Viewed 440 times
I replayed this map and setup. This time I choose to play: 2vrs2 (1 human+1 AI vrs 2-AI) instead of 1 human+2 AI vrs 3 AI's.
And guess what happened?
- No AI-bot jamming / clogging certain areas of the map
- The friendly AI beat me in the race to destroy the enemy-bases ?!

I'm curious why the (friendly) AI did not get stuck anywher on the map this time in this 2vrs2 setup?
Has anyone got an idea?

Matt
Posts: 1048
Joined: Tue May 01, 2012 12:21 pm
Location: Germany

Re: (Naval) AI - Pathfinding question

Post by Matt »

It is hard to tell without watching the replay. Not a mapper problem. The behavior is definitely a bug, but not a simple one to fix. My idea is that those sub-marines are multiple squads. The first 2 are blocking the exit. If squad 3 tries to escape it is stuck. They might not have a target. Sub-marines can't attack land based structures so it may just be a useless armada that is produced mindlessly.

Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

Re: (Naval) AI - Pathfinding question

Post by Ronald »

Matt wrote:
Wed Aug 19, 2020 4:43 pm
It is hard to tell without watching the replay.
If you want I can replay those 2 games - in exact the same setup - again and upload both replays for you.
Matt wrote:
Wed Aug 19, 2020 4:43 pm
The behavior is definitely a bug, but not a simple one to fix.
QUESTION: How exactly do AI-Bots find their enemies / target / other player on the map?:
- Do AI-BOTS already "know" which other map-spawn-points are occupied at the beginning of a game ?
- Do AI-bots try to find enemy units by a means of brute-force scanning the entire map / cell-by-cell ?
- Do AI-bots travel along pre-defined routes toward other spawn-points on the map ?
- Do AI-bots only RE-ACT when they get attacked by another human player and/or enemy AI-Bot ?
- Option 4,5,n?
Matt wrote:
Wed Aug 19, 2020 4:43 pm
My idea is that those sub-marines are multiple squads.
What is - related to this scenario - a "squad":
- Is it a "group of units" from only 1 friendly AI-bot ?
- Is it a "group of units" from multiple friendly AI-bots together?
- Option 3,4,n?
Matt wrote:
Wed Aug 19, 2020 4:43 pm
The first 2 are blocking the exit. If squad 3 tries to escape it is stuck.
What is - related to this scenario - an "exit" ?
Matt wrote:
Wed Aug 19, 2020 4:43 pm
They might not have a target. Sub-marines can't attack land based structures so it may just be a useless armada that is produced mindlessly.
This brings me to the next question How does an AI-Bot seek and/or find it target(s)?

SunTzu
Posts: 1
Joined: Thu Aug 20, 2020 7:06 pm

Re: (Naval) AI - Pathfinding question

Post by SunTzu »

'' How does an AI-Bot seek and/or find it target(s)?''

As far as I know the AI ''cheats'' and has complete mapvision.
I believe the attack priority for superweapons is ''Conyard, Warfactory, Radar.....''

Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

Re: (Naval) AI - Pathfinding question

Post by Ronald »

SunTzu wrote:
Thu Aug 20, 2020 7:32 pm
'' How does an AI-Bot seek and/or find it target(s)?'
As far as I know the AI ''cheats'' and has complete mapvision. '
Hello SunTzu. thanks for your feedback.

QUESTION: Does it matter to the selected AI-Bots if OpenRa's famous "Fog of War" is turned on?
or has this feature only implemented to affect (the map vision of) Human vrs Human players?

SunTzu wrote:
Thu Aug 20, 2020 7:32 pm
I believe the attack priority for superweapons is ''Conyard, Warfactory, Radar.....''
Where can I find out/ learn more about this "AI-cheating" behaviour ?
Inside which AI-Bot configuration files is this attack priority defined ?

Ronald
Posts: 166
Joined: Fri Aug 30, 2019 9:05 pm

Re: (Naval) AI - Pathfinding question

Post by Ronald »

Hello Matt
Ive replaýed this map/game setup and uploaded 3 replays in a zipfile to my Dropbox:
The replays can be downloaded via this link:
- https://www.dropbox.com/s/4a0l46gtjdzcz ... am_2mb.zip

NOTE:
Check out the readme.txt inside it for
- more information about a specific replay file
- Openra version
- hardware / OS specifications of my computer

I'm curious if these 3 replays can help you (or anyone else here) find an explanation for what happened.

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