Basic AI Demo (Now Open Source)

[DarkScythe]

Hi guys, i started developing this 3rd person ai demo to see if i could build a near-complete ai system for a game. Unfortunately it was difficult for me to code such challenging things after 9 hours of work time. With the inability to find some visuals for the demo i lost my appetite and quit after a few weeks. Here you can see what i ve done so far.

Ogre, Physx and OpenAL is used.
Navigation system uses Recast
Steering and decision systems are hand written.
Although the decision system is mature enough(a hierarchical state machine with priorities) the states of the agents are purely written so they do not seem that intelligent.
The agents try to get behind the walls to get cover when they see an enemy. For this i used the sensor grid algorithm which you can read in the ai wisdom 3 book.

With the help of some good looking animations and more detailed agent logic it could be a much more better one.

Download : zzz.rar

Source Code : zzz_source.rar

Short Video : http://www.vimeo.com/12833880

[vimeo]12833880[/vimeo]

[CrimsonGT]

This looks really cool. Why not make a thread at a few artists forums, show off whats done, list what you need, and take a break for a bit?

[dudeabot]

do you plan to release the code? would be really useful for us that are making first/third person shooters too. for example id love to know how you made the enemy aiming system, it looks very similar to how a human does.

congrats!

[DarkScythe]

Sorry my source code is too messy to be open sourced but i can share any knowledge i have.
My aimig system is not actually a system but a few lines of randomiser code It is simple but it does the job for me.
You can tweak the numbers to get better/worse aiming for certain postures like crouching or running.

Code: Select all

Vector3 closest = agent->getKnowledge()->getEnemy(id).GetPosition();
float coeff = agent->GetPosition().distance(closest) / agent->getAttackRange();
Vector3 target = closest;
target.x += coeff * Math::RangeRandom(-1.0 , 1.0);
target.y += coeff * Math::RangeRandom(-0.125*agent->getEyePos().y, 1.50*agent->getEyePos().y);
target.z += coeff * Math::RangeRandom(-1.0 , 0.0);
agent->Shoot(target);

[SimNation]

Hey dude, congratulations for you job. I still believe that a messy code is better than no code at all Think about it.

[maylivios]

OMG, this is exactly what I am looking for!

Is there any way to, you know, share your code?

I would like to see your camera colission avoidance implementation as well as your project structure.

"Hide", "Seek" and "Attack" is perfect for my game, and you already did this.

Congrats!

[DarkScythe]

Ok i opened the source with mit license.
There are minimal comments so it is probably that you will have difficulty understanding the code.
Feel free to ask anything.

[mamairaja]

Excellent, Thanks for releasing the source. I will try to integrate the ai part with mine.

[Sgw32]

Thanks! I'm programming my own Ogre AI engine and my pathfinding system works very badly So I'll use your example code I also want to make my Ogre AI engine free and open-source because I haven't ever seen any example of AI in Ogre!

[madik]

Excellent! But I have problem with this application on vista. After running application i see error "APPCRASH". Any ideas?
I'm polish so errors are in Polish too.
Error:
Nazwa zdarzenia problemu: APPCRASH
Nazwa aplikacji: whatever.exe
Wersja aplikacji: 0.0.0.0
Sygnatura czasowa aplikacji: 4c225adf
Nazwa modułu z błędem: whatever.exe
Wersja modułu z błędem: 0.0.0.0
Sygnatura czasowa modułu z błędem: 4c225adf
Kod wyjątku: c0000005
Przesunięcie wyjątku: 0002f024
Wersja systemu operacyjnego: 6.0.6001.2.1.0.768.3
Identyfikator ustawień regionalnych: 1045
Dodatkowe informacje 1: fd00
Dodatkowe informacje 2: ea6f5fe8924aaa756324d57f87834160
Dodatkowe informacje 3: fd00
Dodatkowe informacje 4: ea6f5fe8924aaa756324d57f87834160

[chaosavy]

Nothing in the error message seems to point towards the problem. I'm Polish too (been living in America longer though). Check your Ogre.log file (it should be in the working directory debut\ or release\) and hopefuly it will give you more leads.

[madik]

This is OGRE log(attachment)

[dudeabot]

this will be very useful for my engine which is using recast too ;D

i have named your engine as zzzEngine =P

thanks

[mkultra333]

Only just found this, looks pretty interesting. I'm trying to find a basic game engine that actually does stuff instead of just being incomprehensibly abstract, and it looks like you've got a lot going here. I'm working on getting it to compile, since it uses a lot of stuff like MyGui that I don't have. If it works I think it might be more useful that you give it credit.

[DarkScythe]

You can just completely remove MyGui since it was like a place holder in this project.
Thanks for all the feedback.

[ACIDImagine]

Let me start by saying great work, I love it

I managed to get it to compile by ripping out ParticleUniverse and MyGUI. It also now starts and loads, however all the players/AI seem to fall through the floor and continue falling... like there's no collision detection...

Any idea on how to fix this? I didn't remove nVidia PhysX and when I try to walk into other players I can't so obviously there is some collision detection but no collision detection with the floor.. bit strange

EDIT: If it makes any difference I'm using v2.8.3 of the nVidia PhysX SDK. Also for some reason when I die I float upwards towards the floor of the scenery.

[DarkScythe]

Sounds like a physx problem(i also used 2.8.3). The level is a triangle mesh shape and all characters have a character controller so they should collide. Be sure to have the latest physx system software.
Also you can try to add some boxes(commented out at the end of Level constructor) to see if they also fall through the ground.
Basically the ai system is not bounded to physx but it is used in various places like projectiles, camera collision, player-level collision etc. so it will need some more effort to make it work without physx.

[ACIDImagine]

The boxes also fall down.. it's strange. Your precompiled executable works just fine, but my compiled one still seems to have collision problems. I ripped out Guisystem, ParticleManager.

Also my Menustate looks like this

Code: Select all

void MenuState::Initialize()
{
	//UISYS->LoadLayout("main");
	//UISYS->SetCursor(true);
	//UISYS->SetCrossHair(false);
	//button callbacks
	//MyGUI::ButtonPtr btnPlay = UISYS->GetGUI()->findWidget<MyGUI::Button>("btnPlay");
	//MyGUI::ButtonPtr btnExit = UISYS->GetGUI()->findWidget<MyGUI::Button>("btnExit");
	//btnPlay->eventMouseButtonClick = MyGUI::newDelegate(this, &MenuState::OnPlay);
	//btnExit->eventMouseButtonClick = MyGUI::newDelegate(this, &MenuState::OnExit);
	SSYS->LoadState("game");
}

Also you have put in Application.cpp:
//PS->Initialize();//do it in states

I couldn't find it in the states so I uncommented it because I thought perhaps it wasn't initializing but I get this error when starting the application:
OGRE EXCEPTION(4:ItemIdentityException): An object of type 'ManualObject' with name 'mVisualDebugger' already exsists. in SceneManager::createMovableObject at ..\..\..\..\OgreMain\src\OgreSceneManager.cpp (line 6484)

[njw1985]

the source code link is broken,would you give a new source code link for download?

[DarkScythe]

It works for me, can you check it again?

[makiolo]

your code its ai junkie style! good work
I am development a similar ai system but more advanced for project final in university.

[njw1985]

It works for me, can you check it again?

I try many times, but can't download.
Could you send "zzz_source.rar" to me? My E-mail address is Thanks !

[fruki]

I'm having the same problem as madik, my Ogre.log shows no clue about what could be the problem.

It works perfectly on my PC, but it crashes on my laptop. Same OS on both: Win7.

[bozykster]

Hi - I have the same problem! When you compile the debug version of the program runs without problrmu. However, after compiling the release version of the program throws me APPCRASH. If you have solved this problem, please advice.

[dragutux]

Hi; me and mironix are working on fixing this (altough we abandonned physx because of the not possibility to use it properly in multiplatform -macos physx do not have gpu support..-) and i will releaase a fixed & compiled version working toward ogre 1.7.2 (it might not use sounds anymore altough)

i'll update this post soon.