Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Mon Nov 12, 2012 10:48 pm Post subject:
Designing an effective AI?
Any tips?
Also, what do you guys think about the vanilla AI? I keep seeing weird stuff like large groups of enemy units moving past each other and ignoring each other.
Is there any sense in attack X missions when X may for example be deep inside enemy base which can't be reached without destroying lots of units and defences first? _________________ Eradicate. QUICK_EDIT
To me, although vanilla AI is varied (lots of differents teams), it lacks aggresiveness, attacking with so few units that you can't be beaten by them. But if I remember well, they have lots and lots of teams staying inside their base, making it very hard to destroy. As a consequence, the game gets frozen, I mean, very few units that can't kill you and too many units stuck into their base means that you can't do almost anything.
To edit TS AI, sometimes I help myself by checking other mods either by playing them or by extracting their AI.ini. To me, right now, the mods that have the better AI are World of Insanity (very old), TS Dusk (old too), The Dawn of the Tiberium Age (new) and Twisted Insurrection (new).
What the first 2 mods have in common are that everything the AI does depends exclusively in what the AI builds, no matter what you do. They attack with waves and waves of units making the game very entertaining and hard.
The last 2 ones have their AI a lot more complex and varied and very challenging as well, plus are made by the same man, Rampastein. You can always ask him for advice too . Because of being that complex I prefer the most to test them instead of opening their AI.ini, but I don't think it's a bad idea, perhaps it's even better than checking the 2 older mods. Anyway it's good to check every hard-AI mod AI.ini, it always helps.
BTW, I've made a tutorial about this, but right now it need some corrections but if you want I can fix it as fast as possible. There's another very good AI tutorial, don't remember who made it but it's very useful, here it is:
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Tue Nov 13, 2012 1:52 am Post subject:
Thanks, I vaguely recall reading this document years ago .
Does any of these mods have a non-cheating AI?
I'd love to read your tutorial.
Anyway, I'm playing with the standard TS AI but with 3x larger infantry teams. Sometimes they can rape pretty hard. I also have much weaker buildings and harvesters, so for example in last game, I basically moved 15 infantry and 3 starting tanks near enemy base.
I waited until the enemy built a Refinery and then when enemy Harvester was returning, I attacked part of enemy base with my infantry and then attacked the docked Harvester with my tanks, quickly destroying it and the Refinery. Before my whole force got destroyed, I destroyed 2 enemy tanks and the Construction Yard. The rest of the game was basically destroying the remains.
Since there was 10000 of starting money the enemy managed to send two large infantry attacks at my base.
After defeating them, I have sent my first big infantry team into city near the enemy base, supported by 3 artillery units. The enemy made another infantry attack which destroyed the infantry and artillery and then when another group of infantry and artillery arrived with 2 tanks, the history repeated itself.
Finally, I attacked with 4 tanks and a big infantry group and destroyed the enemy. I think both forces had 90+ unit losses. It lasted a whole hour.
Still, the AI sometimes does silly things.
What do you guys think about specific missions vs. kill all missions?
And is there any way to avoid enemy task forces passing by each other without attacking? _________________ Eradicate. QUICK_EDIT
DTA and TI have only rules.ini wise a cheating AI. In ai.ini are no cheats possible.
So if you give the ai in rules.ini the same moneybonus as the human player, there are no cheating AIs anymore (except of bugs like the multiple warfactory bug)
Try the different TeamType keys for more different ai behaviour
Annoyance=
GuardSlower=
Whiner=
Aggressive=
Suicide=
OnTransOnly=
AvoidThreats=
IsBaseDefense=
OnlyTargetHouseEnemy= ;if no, this will probably also make the AI attack other enemy units beside the current chosen main enemy. _________________ SHP Artist of Twisted Insurrection: Nod buildings
The last 2 ones have their AI a lot more complex and varied and very challenging as well, plus are made by the same man, Rampastein.
Heh, while I love that I finally get mentioned as the TI AI Coder instead of Dutchygamer getting all the credit (no offense to Dutchygamer, it's an effect of the hype before PB1's release I guess, and the AI coder swapping being done rather silently), I'm not the AI coder anymore for PB4. To be clear, TI's AI coders:
Public Beta 1: Dutchygamer
Public Beta 2: Rampastring
Public Beta 3: Rampastring
Public Beta 4: Dutchygamer
DTA's AI is done entirely by me though.
Quote:
And is there any way to avoid enemy task forces passing by each other without attacking?
AFAIK TI's AI simply has a very large starting money bonus for the AI, while DTA's AI levels have different kinds of relatively complex cost and buildtime reductions for different AI levels. However, you won't find a mod with a good AI that doesn't cheat; even the base TS level 0 AI cheats. The AI engine simply isn't complex and modifiable enough for it to be possible to create a challenging AI that doesn't cheat.
Quote:
What do you guys think about specific missions vs. kill all missions?
I've found that using the Hunt script (originally discovered by SuperJoe, I linked it above), which is practically a complex "kill all" script, for most teams provides very good results. Still, some specific missions are very handy, for example ordering the AI to use stealth tanks for killing your harvesters or flame tanks doing a suicide attack targeting your refineries and bringing down your economy. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
Joined: 18 Jun 2005 Location: Dordrecht, the Netherlands
Posted: Tue Nov 13, 2012 5:44 pm Post subject:
LKO: you are partly incorrect about no cheats in AI.ini. The AI ignores prerequisites, so you can make the AI create units without the proper prerequisites, which can be seen as some kind of cheat. The basic TS AI does this a lot. QUICK_EDIT
LKO: you are partly incorrect about no cheats in AI.ini. The AI ignores prerequisites, so you can make the AI create units without the proper prerequisites, which can be seen as some kind of cheat. The basic TS AI does this a lot.
Unfortunately, if you make the AI follow prerequisites, it turns stupid. There is only one condition the AI can check for; with the way TS AI has been set up, it checks if some units would be effective in the current situation; with the AI following prerequisites it'll instead check if the AI can build the units, without caring about them being a smart choice in the current situation. I personally prefer the AI being smart and cheating with prerequisites instead of following prerequisites but being less "intelligent" at the same time. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
You can avoid the situation where AIs first attack wave has some high tech units that it shouldn't have yet by creating some teams that have max priority (5000), but also have a trigger condition for a fake structure (invisible and indestructible). These teams are preferred when the AI hasn't yet constructed the fake structure, but get disabled as soon as he builds it. Or if fake structures are too hacky for you, could use tech center as the condition, once he has a tech center he stops building the low tech teams.
I use this for rush teams that the AI only uses at the beginning of the match. _________________ QUICK_EDIT
Joined: 18 Jun 2005 Location: Dordrecht, the Netherlands
Posted: Tue Nov 13, 2012 7:55 pm Post subject:
^Rampastein wrote:
Dutchygamer wrote:
LKO: you are partly incorrect about no cheats in AI.ini. The AI ignores prerequisites, so you can make the AI create units without the proper prerequisites, which can be seen as some kind of cheat. The basic TS AI does this a lot.
Unfortunately, if you make the AI follow prerequisites, it turns stupid. There is only one condition the AI can check for; with the way TS AI has been set up, it checks if some units would be effective in the current situation; with the AI following prerequisites it'll instead check if the AI can build the units, without caring about them being a smart choice in the current situation. I personally prefer the AI being smart and cheating with prerequisites instead of following prerequisites but being less "intelligent" at the same time.
Myeah, I once had an AI that followed prerequisites and still was effective, but that was ages ago and I lost it unfortunately. I still think it's the best way to go, but unfortunately TI disagrees with that QUICK_EDIT
Huh? Well my AI for my YR mod totally respects prerequisites and I think it's pretty effective considering the fair few triggers (it's incomplete). Doesn't even clone units. QUICK_EDIT
The effectiveness of the AI also depends on the amount of rules.ini cheats, how well the taskforces and teams have been coded and synchronized with some values in Rules.ini (teamdelays and the amount of defensive teams, for example) and general game design. For some mods it's easier to make an effective AI than for others. So what works for one mod often doesn't work for another mod. In addition, what one considers effective isn't defined and usually depends on the AI coder's playing skills What's hard enough for you can be too hard or too easy for someone else. So it's quite hard to compare the AI of one mod to the AI of a different mod. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
Joined: 18 Jun 2005 Location: Dordrecht, the Netherlands
Posted: Tue Nov 13, 2012 9:44 pm Post subject:
RA2 has the advantage that the AI has a constant cash bonus instead of a single one TS had. My RA2 AI is overall superior to any TS AI I ever created, because the TS AI always runs out of cash at one point. Of course, RA2 has it flaws as well, including one easy way to get loads of cash QUICK_EDIT
RA2 has the advantage that the AI has a constant cash bonus instead of a single one TS had. My RA2 AI is overall superior to any TS AI I ever created, because the TS AI always runs out of cash at one point. Of course, RA2 has it flaws as well, including one easy way to get loads of cash
That advantage exists only for the Normal AI (level 1). With 0 and 2, you can give them cost bonuses by editing the Cost= key in [Easy] (for level 2) and [Difficult] (for level 0). My TS AIs have always made a lot of use of the keys in those sections, except for [Normal] (since that one is used for humans as well as AI level 1). Even my TI AI used Cost=0.75 in [Easy], I'm wondering if that setting is still present.
To give the AI a balanced economy, the DTA AI uses a small reduction in the Cost= value for level 0 (because the damn level 0 AI is hardcoded to build only 2 harvesters) and a very small MPAICM bonus; level 1 simply has a very large MPAICM bonus and AI level 2 has a rather small MPAICM bonus but a large cost reduction for everything given by the edited Cost= value, which makes the AI never run out of cash unless you succesfully harass its harvesters. Last edited by ^Rampastein on Tue Nov 13, 2012 9:56 pm; edited 2 times in total QUICK_EDIT
Joined: 22 Nov 2010 Location: Iszkaszentgyorgy, Hungary
Posted: Tue Nov 13, 2012 9:53 pm Post subject:
Dutchygamer wrote:
RA2 has the advantage that the AI has a constant cash bonus instead of a single one TS had. My RA2 AI is overall superior to any TS AI I ever created, because the TS AI always runs out of cash at one point. Of course, RA2 has it flaws as well, including one easy way to get loads of cash
So it's quite hard to compare the AI of one mod to the AI of a different mod.
But when the units are similar or do the same role I think it's not that hard.
For example, many mods have a basic light infantry, a regular tank (in vanilla TS, Tick and Titan), an artillery (in vanilla, Juggernaut and Nod Artillery), Nod has a buggy, a bike, a stealth tank, a flame tank, GDI and Nod have their respectives APC, GDI sometimes has a heavy tank (Mammoth), etc.
It's like there's a basic skeleton common to some TS mods and also to some other C&C games, that can help you to use a parallelism on what units do and how to attack. _________________ Inactive Projects >> Tiberian Sun: Tech Level War http://www.ppmsite.com/forum/index.php?f=843
Download the latest beta: http://www.moddb.com/mods/cc-tiberian-sun-tech-level-war QUICK_EDIT
Joined: 18 Jun 2005 Location: Dordrecht, the Netherlands
Posted: Tue Nov 13, 2012 10:20 pm Post subject:
@Rampastein: hmm, I need to look into those Cost modifiers one day. And the stuff you used for the DTA AI is something that currently goes over my head. I'll make note of it to look into DTA's ini files one day.
@Graion Dilach: why am I not surprised about that. Still, it's a funny bug I like to exploit on low-money maps
@TiberFCSL: there is a difference between having an AI which just throws groups of various units at you or actually uses units for which targets they are meant. That, and some mods want to have a more dynamic AI then the standard AI. QUICK_EDIT
AFAIK TI's AI simply has a very large starting money bonus for the AI, while DTA's AI levels have different kinds of relatively complex cost and buildtime reductions for different AI levels. However, you won't find a mod with a good AI that doesn't cheat; even the base TS level 0 AI cheats. The AI engine simply isn't complex and modifiable enough for it to be possible to create a challenging AI that doesn't cheat.
Oh.
^Rampastein wrote:
Quote:
What do you guys think about specific missions vs. kill all missions?
I've found that using the Hunt script (originally discovered by SuperJoe, I linked it above), which is practically a complex "kill all" script, for most teams provides very good results. Still, some specific missions are very handy, for example ordering the AI to use stealth tanks for killing your harvesters or flame tanks doing a suicide attack targeting your refineries and bringing down your economy.
Ah, the hunt script. I remember using it extensively in my old mod.
So, it's basically the best for non-specialist units?
Does it work well with artillery?
^Rampastein wrote:
Dutchygamer wrote:
LKO: you are partly incorrect about no cheats in AI.ini. The AI ignores prerequisites, so you can make the AI create units without the proper prerequisites, which can be seen as some kind of cheat. The basic TS AI does this a lot.
Unfortunately, if you make the AI follow prerequisites, it turns stupid. There is only one condition the AI can check for; with the way TS AI has been set up, it checks if some units would be effective in the current situation; with the AI following prerequisites it'll instead check if the AI can build the units, without caring about them being a smart choice in the current situation. I personally prefer the AI being smart and cheating with prerequisites instead of following prerequisites but being less "intelligent" at the same time.
Hmm...
Maybe pre-requisites would better be ditched altogether and simply replaced with higher high-tech unit costs or something?
Dutchygamer wrote:
Myeah, I once had an AI that followed prerequisites and still was effective, but that was ages ago and I lost it unfortunately. I still think it's the best way to go, but unfortunately TI disagrees with that
What was it based on? _________________ Eradicate. QUICK_EDIT
Joined: 18 Jun 2005 Location: Dordrecht, the Netherlands
Posted: Wed Nov 14, 2012 11:14 am Post subject:
Sorrow wrote:
Dutchygamer wrote:
Myeah, I once had an AI that followed prerequisites and still was effective, but that was ages ago and I lost it unfortunately. I still think it's the best way to go, but unfortunately TI disagrees with that
What was it based on?
It was a hard job of searching what units where used for what team, and changing the triggers for the teams to only fire when the AI owned the proper structure (I always choose the highest tech structure, like Radar or Tech Center). Downside are that 1. it takes loads of time to change all the triggers 2. if you change the units in the teams you must also change the triggers and 3. the AI can build teams which are not useful (creating a team to hunt a Temple of Nod while no Temple of Nod is on the map). I personally found that only a mild inconvenience (as the AI will always default to 'kill-em-all' if it can't find its target) but I had some nasty experiences when trying this way with the TI AI, up until completely breaking the AI and having to start from scratch again QUICK_EDIT
... but I had some nasty experiences when trying this way with the TI AI, up until completely breaking the AI and having to start from scratch again
I believe that a large part of the cause for the AI breaking was TI PB1's ridiculously low TeamDelays values. IIRC it used a value of 50 or something like that for the Hard AI (level 2), which means that the AI will start building a new team every 50 frames. And with gamespeed 5 on singleplayer, 1 second = 60 frames. So, the outcome of the AI trying to build a new team more often than once in a second isn't really hard to guess; the AI will try to build dozens of teams at the same time but it doesn't get any of them finished until they're broken by DissolveUnfilledTeamDelay (and the units left in the AI's base in guard mode). As a result, the AI will just spam units endlessly but will never do anything with them. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
I don't know what the bold marked 1 does, but that's one difference and a possible explanation
Do you tested these on all 3 difficulty levels?
Narrow down the problem, by changing one of the other trigger step by step to the same stats as the working one. _________________ SHP Artist of Twisted Insurrection: Nod buildings
Any ideas why this doesn't build any team or builds just a few infantry pool teams?
Your taskforces are messed up.
[INFBRIG2-G]
Name=Infantry Brigade
0=4,E1
0=1,ARTY <------ Needs to be 1=1,ARTY
Group=-1
[INFBRIG4-G]
Name=Infantry Brigade
0=4,E2
0=1,ARTY <------ Needs to be 1=1,ARTY
Group=-1
Also dunno if generic prerequisites can be used in triggers (FACTORY). I would simply create seperate triggers for each side to avoid problems and make the AI file cleaner.
Is there a specific reason why [INFBRAT2-G] has TransportsReturnOnUnload=yes? There are no APC type units in the taskforce. _________________ QUICK_EDIT
Is there any way to make groups with units of different speed stick together?
Unfortunately, no. TS lacks one critical script action that RA2 has,
53,0 = Gather (at enemy base)
Even in RA2 the units move at different speeds, but they stop to regroup outside your base before finally attacking you. What I've done in TS is create AI-only copies of units that have adjusted speeds. This way all the units in the taskforce have roughly the same speeds and stick together better.
Once managed to kinda create a workaround for the RA2 gather command, but it was hacky, messy and didn't always work. Need Hyper to look into implementing it for TS. And better yet, implement something that makes the entire team move at the speed of the slowest unit. _________________ QUICK_EDIT
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Sun Nov 18, 2012 9:50 pm Post subject:
Oh.
One thing that I have noticed that now basically all my games look like this - the game starts, we build barracks, I send out 5 E1 to take out a harvester, preferably with a refinery.
Then I send out 15 E1 to take out another harvester and stay near the enemy base.
Then I send out reinforcements, for example 5 E3, and 2 ARTY.
And that's where the AI basically loses.
They never get to build their own ARTY team. Is there any way to make the AI build more units and act more offensively instead of building a refinery after refinery and building harvesters first then they build a war factory? _________________ Eradicate. QUICK_EDIT
Is there any way to make the AI build more units and act more offensively instead of building a refinery after refinery and building harvesters first then they build a war factory?
Give their Taskforces more units and lower TeamDelays, MinimumAIDefensiveTeams and MaximumAIDefensiveTeams. And lower those values a lot. Try leaving it with only 1 defensive team (both min and max), and use something like 500 for TeamDelays for a start (don't go much lower than this, especially if you make your taskforces larger). Should make it much more aggressive.
TiberFCSL wrote:
But when the units are similar or do the same role I think it's not that hard.
For example, many mods have a basic light infantry, a regular tank (in vanilla TS, Tick and Titan), an artillery (in vanilla, Juggernaut and Nod Artillery) ...
True, while many mods have these same roles, the effectiveness of those roles varies greatly in different mods and games. For example, infantry are very effective against just about anything in normal TS, while in DTA's Classic Mode they're pure cannon fodder lategame and as such the DTA CM AI doesn't build nearly any infantry after the first few mins of the game. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Tue Nov 20, 2012 2:08 am Post subject:
Thanks.
Is there any way to make AI harvesters non-retarded? They tend to go very far from their base, even to a tiberium field next to my base despite that they have fields near their own base. _________________ Eradicate. QUICK_EDIT
Is there any way to make AI harvesters non-retarded? They tend to go very far from their base, even to a tiberium field next to my base despite that they have fields near their own base.
By observing mods with good AI, i came up with the conclusion that harvester retardness is hardcoded to the game QUICK_EDIT
One way to prevent that is by reducing the value after TiberiumFarScan= under [AI] in rules.ini, although they'll run a greater risk of running out of tiberium to harvest then (especially on large maps with little tiberium nearby). _________________ QUICK_EDIT
I don't even know why Westwood coded the Harvesters to prefer Tiberium that's at the edge of their scan, not that which is closest... _________________
Fun fact. In a strategy magazine about TS it advised to harvest the Tiberium fields far away so you'd have those near as a reserve. _________________ Free Tibed!
EA for worst company of the decade! QUICK_EDIT
Harvester take often the first discovered tiberium field in their FarScan range. It seems that the AI even uses the sight/scouting of the human player.
Since
-many maps are small and have the starting locations close to each other
-human player start scouting much earlier than AI
it causes the AI harvs to see the tiberiumfield that the player discovered before they find their own field.
Thus AI harvs often harvest on the player field, while there are others much closer fields. _________________ SHP Artist of Twisted Insurrection: Nod buildings
Indeed, unless you wanna move the refinery higher up the tech tree. Since you obviously wouldn't also want this to apply to human players, you'd have to make a clone of the refinery which is buildable for the AI only. Give this cloned refinery Prerequisite=FACTORY, TechLevel=-1, and AIBuildThis=yes, while giving the original refinery AIBuildThis=no.
Also don't forget to change BuildRefinery= under [AI] to the cloned refinery.
Now the AI should always build the war factory before building the war factory. _________________ QUICK_EDIT
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Sun Dec 16, 2012 7:26 am Post subject:
Doesn't the AI ignore prerequisites?
Anyway, maybe I'll simply increase the costs of war factory so that it would be reasonable for player to build refineries first. _________________ Eradicate. QUICK_EDIT
At least for RA1 the far and near scan values for harvesters are also used for player's harvester lol. Not sure if this also applies to TS but it probably does, just a quick reminder. QUICK_EDIT
Joined: 10 Dec 2012 Location: I'm too busy conquering the world!
Posted: Mon Dec 17, 2012 2:35 pm Post subject:
Is it possible to have an AI that shift their focus to various players after a while instead of targeting a player until that player die?
Lets say for like 5 minutes AI focus on player 1 then switch focus to player 2 for maybe like 2 minutes then to player 3 and so on. _________________ Mod Leader and founder of World Domination
Joined: 10 Dec 2012 Location: I'm too busy conquering the world!
Posted: Mon Dec 17, 2012 4:16 pm Post subject:
^Rampastein wrote:
Zero18 wrote:
Is it possible to have an AI that shift their focus to various players after a while instead of targeting a player until that player die?
Not really, but you can make it entirely random instead of targeting a single player. Then you can't control at all which player the AI targets, though.
Yes, but how do I make it so that AI will just randomly attack any players? Also another question, if I'm making 5 starting locations and I want the AI to be always on the center of the map? _________________ Mod Leader and founder of World Domination
It's impossible to control exactly where human players and AI players will start. The best thing you can do is making the human players and AI players start in the same locations and then having the human players manually move their MCVs to a different location after the game has started. _________________ QUICK_EDIT
I'm usually massacring the AI with a rush before it builds a factory. Any idea what I'm doing wrong?
If you mean that it's not building any factories fast enough, you're giving it a bad build order. If you mean that it doesn't build a vehicle factory fast enough compared to you, same. If you mean that it doesn't build a vehicle factory until you've rushed it with infantry, your TeamDelays are too high. Lower it so the AI will build some infantry teams to defend itself with against your rushes. _________________ CnCNet Client | CnCNet TS patches | More Quality-of-Life Improvements for RA Remastered
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Thu Dec 27, 2012 1:45 am Post subject:
^Rampastein wrote:
Sorrow wrote:
I'm usually massacring the AI with a rush before it builds a factory. Any idea what I'm doing wrong?
If you mean that it's not building any factories fast enough, you're giving it a bad build order. If you mean that it doesn't build a vehicle factory fast enough compared to you, same. If you mean that it doesn't build a vehicle factory until you've rushed it with infantry, your TeamDelays are too high. Lower it so the AI will build some infantry teams to defend itself with against your rushes.
I often build two big infantry teams, one of them destroys the Harvester and drags away the enemy base defence army, then the second one goes in and destroys the Construction Yard.
Usually the whole task force gets destroyed but the enemy is crippled.
Then they usually attack me with all they got and I barely defeat them in my base.
Another option is that I build up and engage in a slow battle near their base until I outproduce them and I'm able to send in more infantry supported by artillery and massacre them since they don't have a war factory.
They have infantry teams but they can be easily dragged away from critical buildings. _________________ Eradicate. QUICK_EDIT
Joined: 17 Nov 2004 Location: The Most Holy Metal Reich
Posted: Thu Dec 27, 2012 9:22 pm Post subject:
^Rampastein wrote:
Sorrow wrote:
They have infantry teams but they can be easily dragged away from critical buildings.
Maybe you could lower its BuildTime (in [Easy]) and TeamDelays, so it'll build infantry slightly faster than you and make your task harder.
I don't want the AI to build faster than me. Is there any way to make a defence team that will just guard the Construction Yard? _________________ Eradicate. QUICK_EDIT
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