SF's Hammer Tutorials - NPC Navigation

Learn how to use the info_node entity to enable NPCs on your maps to navigate properly.
Rundown:
First, we learn how to best place the info_node entities around our maps.
Then we learn how to edit the nodes ingame, as well as how to debug the navigation by using the console to order a NPC around the map.
Made by Silverfish
orsvarn.com

[@AgrimarYT]

You know hammer is old when a 2009 Tutorial is still relevant. amirite?

[@Silwerfish]

+Agent Agrimar Animations hehe yep! :D

[@Espinete87]

I still using it, its my first map, im 31 years old, and this kind of things are lovely! :D i hope many people still doing it By the way, i uploaded quick video very interesting, to learn how to export props from gmod to hammer, this is gold! kzbin.info/www/bejne/oqbWlIJ-o9ycpNE

[@maxwell_edison]

You know Hammer is old when a 3-year-old comment on a 2009 tutorial is still relevant. amirite?

[@pittos838]

god bless source 2 and the fact this tutorial is still relevant for it (kinda)

[@Electronic424]

You know Hammer is still relevant when you reply to a video from 2009 claiming Hammer is old. Unreal Engine still uses many of the same tools and features it did back in the early 2000s, some things are just timeless my friend.

[@RadRoach4422]

He told us to rate the video. *He told us to rate the video.*

[@yodigochau]

he told us to rate the video

[@gamingwithvega8366]

НЕ ТОLD US ТО RАТЕ ТНЕ 𝓿𝓲𝓭𝓮𝓸

[@MrGermandeutsch]

It's *_2020_* Corona Virus and Leaked Source Codes plague the Lands. And I'm re-watching this Video again, after 10 years, to learn once again on how to properly use the Ground Node Entity.

[@lunareclipse2401]

mood

[@ozone_au]

2022 now man. u remember how to use the entity or do u need to rewatch again?

[@MrGermandeutsch]

@@ozone_au Funny that you mention that today of all days. Because I *_did_* start working on nodes again and forgot everything YET AGAIN.

[@ozone_au]

@@MrGermandeutsch LMAO good luck man haha

[@traveler1710]

ye@@MrGermandeutsch

[@DanJacobsonDANJ16]

Do info_nodes affect performance in-game? How many info_nodes can you create in a map? Is there a particular limit?

[@Silwerfish]

As far as I know there is no noticeable performance impact nor any particular limit to the number of nodes you can add.

[@thedrenchedkyogre7096]

I know this is an old comment but no, not at all! (Unless there are like, Billions of nodes then yes there would be a difference.) The only thing the nodes are effecting are the file size. The more nodes, the bigger the size of the bsp file will be.

[@sasanekpl1130]

My god, almost 12 year old piece of information is still revelant nad useful today. Thanks!

[@gsp1995]

Oh dude, you rule. Very helpful tutorial, since I like to work more with NPCs and scripted sequences other than brushwork lol. But I really needed to understand the info_node thank you very much.

[@koldproxy]

An extra note to all testers: If you want to try Combine (hostile NPCs) just type "notarget" in the console so they won't kill you.

[@Silwerfish]

Thank you! :) I have the game running in the background though. See my tutorial called "NPC Animations", use the scripted_sequence, but give no animation information. The NPC will walk to the scripted_sequence and then consider himself to be done. You can then set "Next Script" to the name of another scripted_sequence and then you can tie the last scripted_sequence to the first one and your NPC will be in an endless loop. Just don't forget to check the "Override AI" flag! I hope this helps.

[@Silwerfish]

You can use an aiscripted_schedule to tell them what to do. So you set up a bunch of those. And then you can use a logic_random_outputs entity that has all the aiscripted_schedules in it. Then you tell that logic_random_outputs to fire every x seconds by using a logic_timer. This is one way of doing it that I think should work, but I haven't worked with the logic_random_outputs entity so I can't say for sure.

[@Silwerfish]

@IXIArblargIXI It's not that they ignore them (the nodes are just for enabling your NPCs to navigate your level, it doesn't force them to do so), it's just that they are not programmed to start wandering around when they spawn. You could add an aiscripted_schedule that you trigger when a zombie spawns that tell the zombie to go towards the player and attack him for example, but I don't think there is a good way to just make them wander aimlessly.

[@Silwerfish]

You don't need to think of anything special most of the time, you can place them like you would on normal flat ground. Doing it like I do in this video you won't have to guess either, you can just place them and instantly see if they connect properly or not. :)

[@Silwerfish]

@Steampr0x1m4 The command is actually map_edit, not edit_map. :)

[@Silwerfish]

@thehumor There are several ways, I'd say the easiest way is to use a scripted_sequence entity. See my tutorial called NPC Animation to learn how to do that (just ignore the actual animation part, because without an animation to do, the NPC will just move to the position).

[@wojciechkoczorowski9790]

Is there a way to make your own links with the nodes, instead of them automatically join?

[@Silwerfish]

I'm pretty sure that nav_generate is something for bots (like for TF2 and CS:S for example) while nodes are for AI (NPCs).

[@MrGermandeutsch]

how i should place the nodes on stairs?

[@Silwerfish]

I'm very glad you found it useful! NPCs and AI is something I love playing around with. Thank you! :D

[@Silwerfish]

I don't know how GMOD works, but if it works like other Source games then you should be able to use path_corner entities like you mention. I don't know if there's built in support for making NPCs wander randomly, probably not, but you can always make your own, though that would be a bit of work.

[@Silwerfish]

I have already made a tutorial on NPC animation, wich would be how the pressing of the button would be created. The talking part would be choreography though, so I've added that to the tutorial list. Thanks!

[@NightscoutHL]

never mind, I found that problem(it wasn't the nodes), but I have a new one. I'm making a zombie siege map for gmod, and i put nodes on all the openings in this little house that they are supposed to break into. But they don't storm the house, they just stand around out there unless you go out, start shooting and causing chaos. Help!

[@ryano1267]

Silwer a question. How do you actually make NPC's go somewhere in the game? If i want an npc to be walking right next to a door, how do I do that?

[@Silwerfish]

Have you followed the tutorial to make sure the nodes connect properly and that they are placed where they should be? The nodes don't make the AI move, they just tell the AI where they CAN move, you'd need to use for instance an aiscripted_schedule to make an ai move somewhere.

[@scottishsquid]

i know this tutorial is old, but my nodes just dont appear no matter what i do, like i type the console commands and just.. nothing? I know I have them placed, I can see them in the editor

[@IXIArblargIXI]

Is there a way to link specific nodes to a specific NPC?

[@ringpop6482]

I did the edit_map command in console, and my game just crashed. How can I fix this?

[@marionuggets7743]

Well its a old tutorial

[@letmedwight]

With me this green web is not connected to the info_nodes

[@Soulslayerzx]

I don't know if it makes a difference, but I have no sound on my cpu currently. The info_nodes seem to make of no use, is your mod based on ep2?

[@IXIArblargIXI]

I know theres a way to link path_corner to an NPC, I can do that without a problem. I just want my zombies to wander freely among my map after they spawn, yet they ignore all nodes I place :|

[@paintcan176]

@Thelillfredde click the little grey pawn icon in the toolbar on the left (4th down) and click again to place in your level. now select the red cursor tool from the left (1st icon) and double click the pawn (entity, if you want to get technical) and in the 'class' drop down box scroll down to find anything with npc_ in the name eg: npc_zombie is a zombie. click apply when you have selected one and the green guy will change into your chosen npc.

[@cafedormido]

do you think you could make a tutorial with jump/air nodes

[@theRPGmaster]

Mycket informativ, och fortfarande relevant. Thanks!

[@NightscoutHL]

I didn't use half as many nodes as you did, and every time I tried to load, it crashed because there were too many. I HAD ABOUT 12!!!

[@Silwerfish]

I don't think that's possible, I have seen servers with NPCs though, but I don't have any idea about how they achieved that. It's not supported, I can tell you that much.

[@Silwerfish]

@LuiDeca Yes I do, I can't link here, but just search for it in my videos.

[@Silwerfish]

This does not have anything to do with ordering NPCs around. It's just about giving the NPCs knowledge about where it can go.

[@Silwerfish]

@idonthatethissite I don't know actually, you can place them pretty far away though.

[@Peekofwar]

--What do I do if my nodes are invisible in the 3D view? -- Apparently spin the camera around. lol Oh wow. Maybe it's GMod's Hammer specifically, but if I move around the 3D space, the node appears and disappears at certain angles and positions.

[@Silwerfish]

Using an aiscripted_schedule for example.

[@DirtyOldSkunk]

Good video, but question: in GMOD, is there a way to use these nodes so that when the game starts, the NPC's automatically start wandering around? I know you can use path_corners for them to follow a specific path, but I want them to randomly walk around, and I dont want to go through the trouble of making paths for EVERY single NPC. Can this be done?

[@Silwerfish]

Thank you. The limit for them to be able to walk up it is 16 units, if you can't lower it to that you can use info_node_hint entities to enable them to jump up or down from there. You will need to place one at the top and one at the bottom of the jump (I don't have my good computer so I can't give you the specifics), just experiment with the settings.

[@Fidchell]

What about floors with displacements? When I go to map_edit some of the links are red, and I assume that means the NPC cannot navigate them, but I can lift the connection or the node itself up or anything. The NPCs following me decide to take other routes instead of going straight to me.

[@Silwerfish]

@JakeSpringhorn It should work pretty much the same way. Just make sure the displacement would be easy to navigate. I haven't had any trouble with nav meshes on displacements at least. Did you try adding another node in between the two problematic nodes?

[@bocca882]

Very nice man. What do you have next on the tuto- list?

[@baumus8278]

how do i make strider nodes?

[@NightscoutHL]

do you have a tutorial for that?

[@MrNiicolai]

The best hammer tutorial I have ever seen !

[@LGLFanTeam12]

Do you have any tips for npc_vehicledrivers?? I mean is it interrupting the path_corner of the vehicle?

[@scruga]

some great tuts you got here :) But i have a problem, is it possible to have an npc jump up to something? I have this really small ledge (10-20 hammer units) but they won't climb up it. It's easily jumpable.

[@pompuslompus964]

Why are some of my nodes red? not the connection, the nodes are red and npcs don't use them. Some of the npcs spin in circles while slowly moving in a random direction which is weird. I think it mostly happens on uneven terrain, I tried making the nodes higher but that doesn't seem to do anything?

[@Silwerfish]

Are you absolutely sure there is nothing stopping the nodes from being created? Is the ground flat enough? does the node have line of sight to another node that is also close enough to get connected? I'm not sure what causes your issue, it was so many years since I worked with the Source engine, but those are some ideas at least.

[@pompuslompus964]

They do have a line-of sight and they do connect, regarding the ground the nodes that don't work, they are mostly the ones that are on displacements, but this confuses me because I read that placing the nodes above the ground would Solve that problem which is what I did, but they still don't work. After enabling ai_nodes and ai_show_connect, most of the nodes in the air are red while the nodes on flat ground level were green. Npcs only use Specific red nodes and all the green nodes. The displacements are more like small hills, nothing huge.

[@Silwerfish]

Hm, I wonder what the issue could be.. I'm sorry I can't help you. Hope you're able to figure it out!

[@Fidchell]

@Silwerfish Yes, I have tried that. It's a mess...if you have the time...do you think you can take a look at the vmf? I'll send it to you if you would like to.

[@RickRay9]

@Carmine377700 yeah garry's mod automaticly creates nodes :)

[@edenem]

This isn't working for my CSGO map. My CT is still walking into walls and standing on chairs.

[@TheMagmaCubed]

You need to use a navmesh and not nodes. You can edit it using nav_edit 1 with SV_cheats enabled.

[@Silwerfish]

@Th3Jugg3rn4ugh7 When you do map_edit you lock the editor, you'll need to exit the map to unlock it. Are you entirely sure you did that?

[@yandr0]

2020 and this is a huge helpful? Thanks!

[@xweert711]

Oh hi Lukas! I was sending this to a friend who was just getting into Hammer. Fancy seeing you here. How's Overgrowth doing?

[@Silwerfish]

+xweert711 Overgrowth is going well, thank you! Glad to hear you're recommending my videos! ^^

[@xweert711]

Silverfish (Lukas Orsvärn) Glad to hear it! Have a nice day! :)

[@RonDucats2]

@Silwerfish Ah yes, I saw on your Moddb account, sad. When I have time I'll be checking out the rest of your tutorials. Thanks for what you've done though xD

[@iceydiver]

dose this work with tf2?

[@Espinete87]

Hello, could you tell me how do you use the 3d view to place nodes? im confused, becouse with 3d view you cant place props or do anything, the 2d view is phrustrating >.

[@snudge763]

Are you from finland or sweden

[@Chickengbs]

How do I link the nodes together?

[@johncroissant]

They Start Linked, It Doesn't Show The Lines For Some Reason, Hope I Helped!

[@MrGermandeutsch]

:O this makes so much sense! does you know how i can add synergy on sdk? i tried it one time! but there was no lines!

[@TheSpace928]

How do I make an enemy entity follow and attack the player?

[@Cd5ssmffan]

TheSpace928 if they are marked as an npc_combine_s, your enemies, place nodes and automatically the npc will go to the player using the nearest and fastest route marked by those nodes.

[@TheSpace928]

Thanks. ;-)

[@Cd5ssmffan]

no problem, just try to cover as much space as you can

[@TriWaZe]

Do chickens follow these node paths? Because im tired of them running straight into walls nonstop. And currently my damn bot just stands in a corner in ct spawn and jumps up and down lol.

[@Silwerfish]

No, CS:GO uses a completely different navigation system, these nodes won't do anything for that. Check it out on the Valve dev wiki!

[@Silwerfish]

@Soulslayerzx Your sound shouldn't make a difference. I'm using ep2 yes.

[@FanTazTiCxD]

@Silwerfish You know how to navigate the bots? Well teach me then :O I really need to know!

[@blanch27]

Whenever I run my map and use the command map_edit gm_devcity (my map name, I do have it saved as gm_devcity) It just brings me to a normal singleplayer game with all my addons... Can anyone Help me?

[@Silwerfish]

I don't know what the issue is, but my guess would be that Garry's mod does not support using map_edit. I'm assuming you're using Garry's mod since your map's name is prefixed with "gm_". There could be some other better way of doing that part nowadays, since this tutorial is soon 8 years old.

[@blanch27]

Silverfish (Lukas Orsvärn) Would you know what that is?

[@Silwerfish]

Unfortunately not. It was many, many years since I worked with the Source engine.

[@fighder2]

I was making a cs go map, and my CT bots are running into a wall prop and trying to jump over it onto the ground behind the walls which i don't want them to go to, what can i do

[@Silwerfish]

I don't know how bots work in CSGO I'm afraid, sorry!

[@fighder2]

I got the problem solved :D I just needed to make the nav mesh from raw :P

[@Silwerfish]

fighder2 Alright, good! Thanks for saying how you fixed it in case someone else comes by with the same problem! :)

[@Fishy_Chameleon]

fighder2 what is an nav mesh im sorry im a newb in hammer

[@fighder2]

google navigation mesh hammer editor and you will find it, source has a dedicated page on making nav meshes. You can think of nav mesh as paths for the AI and you basically draw the path out. Usually the engine build the path but sometimes it doesn't work out and you have to set the path manually.

[@123ilikecheese456]

do one were you make them combine not attack you

[@Silwerfish]

Thanks! I haven't actually decided yet, so give me requests to help me make up my mind! ;D

[@Ayahuasca98]

Will it help with making tf2 maps

[@Silwerfish]

Unfortunately not, that game uses a different system.

[@DcsealCMB]

It's so sad how many gmod maps don't have nav nodes, because the creator was too lazy to take the 10 minutes to do it.

[@frze5386]

Like me :(

[@oklol496]

hah i was about skip doing it just from lack of tutorials.

[@Silwerfish]

You're welcome, glad you liked it! :)

[@Silwerfish]

That's in this tutorial that you're commenting on right now. :P

[@thevideoguy666]

Europeans do the best Hammer tutorials. =P

[@sulphurous2656]

still useful in current year

[@yougnomed630]

thanks mate

[@Silwerfish]

@cafedormido That's a good suggestion, thanks!

[@greenlemon9155]

yeah , pretty outdated , that is sad , nw we got a nav_mesh

[@teslavet2625]

Thanks alot man!

[@Silwerfish]

Please give me tutorial requests! :D

[@Silwerfish]

@FanTazTiCxD Go to developer (dot) valvesoftware (dot) com and search for it. I might make a tut on it in the future.

[@Silwerfish]

@JakeSpringhorn Sorry about the late reply, yeah just send it to me, I'll take a look.

[@cptray-steam]

thanks!

[@fbiagentmiyakohoshino8223]

this video is almost a fucking decade old lol

[@scruga]

@Silwerfish ok thank you i'll try :)

[@Silwerfish]

Thank you!

[@sickman2233]

lol just go in your map and type in the console nav_genarete

[@Silwerfish]

That is when using a newer system that doesn't exist for HL2. For NPCs in HL2 to be able to navigate you need to do like I do in this tutorial.

[@kokosik21]

nav_generate is shitty, navmesh is only for bots and nextbots

[@alecz3843]

AI nodes and nav mesh are different things.

[@McStebb]

Thumbs, bro. Thumbs.

[@123ilikecheese456]

yeah i saw it thx

[@Silwerfish]

Thank you! :)

[@Silwerfish]

@Tabe112 Hehe, tack så mycket! ;D

[@Silwerfish]

I have never done that so I don't know.

[@PeterLakeTV]

Hey, thanks! :)

[@Silwerfish]

@fumanchu3cp Awesome, thanks! :D

[@MrGermandeutsch]

maybe if you know it ONE DAY then please tell me / make a tutorial :)

[@Silwerfish]

I don't know actually, I've never tried!

[@sussiestmaninworld884]

I'm an NPC

[@DrewHelander]

How do you make npc go up stairs?

[@theRPGmaster]

Mycket informativ, och fortfarande relevant. Thanks!

[@wojciechkoczorowski9790]

Is there a way to make your own links with the nodes, instead of them automatically join?

[@adamcf1297]

Tekky Yes. Just make a first one, then shift and drag to make a path.