Ranting and raving about games in all aspects good and bad. Also anything else I want to drivel on about.
Why are we wandering in a fog?
Published on June 11, 2009 By Sanguiniusnz In PC Gaming

What is it with Fog of War? This has been possibly the least innovated aspect of RTS games since the genre was first brought out. Since the days of Dune and C&C fog of war has been the only real way to control a players ability to see everything that is going on and while it does the job it feels slightly unsatisfying.

It feels contrived, its like the game developers just shrugged ran with it and have been running with it ever since. The average human can see car sized objects coming from kilometers away given good eyesight and good conditions yet in the majority of RTS games out there I barely feel as if my units can see more than 20 meters away. I feel like my units are all short sighted and wear huge lensed glasses.

It also seems to negate the usefulness of terrain as a vision stopper, if we cant see anything inside the fog what reason have developers got to program it in that if unit A is behind a hill unit B cannot see them until the hill is not longer causing an obstruction. While yes we play games so much in the way of strategy and tactics is taken out by the use of the fog of war, Example,  the simple ability of being able to hide artillery units behind a hill and use a spotter to sight for them, enemy cannot see them because they are behind the hill they have no idea where the shelling is coming from the only thing the know is that they can see a spotter. Don't want the enemy to be able to see inside your base build a wall block their vision.

On the flip side much of this has to do with the scale of the game and the size of its maps. Take DoW2 for example, when controlling a genetically engineer super human who happens to be wearing a suit of power armor that enhances visual capabilities I find it hard to be believe that I can't see more than 20 meters in front of me, however the scale of the map would mean I would be able to see from one side to the other given no intervening obstacles. However there is plenty of terrain that blocks vision buildings, rock outcroppings, walls etc. Why limit my units vision with an artificial aspect of the game? Why not just let the natural terrain features do it for me? Also why exactly can I see exactly whats on the other side of a wall that towers above my head and is solid stone?

Supreme Commander had an ideal opportunity for developing this, terrain was implemented with varying heights could block incoming projectile trajectories etc, yet your units are still wearing thick lens glasses and terrain has no bearing except to make certain parts impassable etc.

Something that has eternally frustrated me as to why in almost every single rts game I have played there is always a sniper unit that can shoot further than they can see, THEY HAVE SCOPES FOR A REASON! Take any FPS game take a sniper rifle and on some maps you can and will be picking people off on the other side of the map before they can even make you out as a small dot on the landscape. Why oh why in every RTS do snipers have to have someone spotting for them to make the best use of their range?

While I cannot disagree that Fog of War does its job, it does however limit many aspects of strategy and I suspect of map design. Without true line of sight the use of vision imparement tools such as smoke greandes or even weather conditions do little more than add visiual effects or use a mechanic such as reduce damage for a limited time period instead of what they are supposed to be for which is to prevent the enemy from knowing what is going on. Using true line of sight opens up a world of possibilities for both smaller scale squad based rts (looking at DoW2 and Company of Heros) and larger scaled games like supreme commander.


Comments (Page 1)
on Jun 11, 2009

Technically coming up with a line of sight algorithm that can check all units in the game individually on the fly would be one hell of a challenge.  I've no idea how they could do that, beyond making it actually an extremely simple algorithm.  I guess you could make it so it only updated as units move or come in to range of other units...but then you would get massive performance hits as you move your army.  If you were to make it extremely simple then tons of people would be raving on the forums about how the LOS was shocking as they point out it's floors.

Ever wonder why AI's or Bots can always see anywhere on a map?  Well if you are working with LOS for the player then you have another issue, you surely have to make the AI follow the same rules so you have to work out his LOS all the time aswell to make sure he can do actions or not.


Currently shooting LOS in RTS is as simple as is x/y(/z) within range?  Yes then check LOS from unit A to unit B, yes I can shoot or no I can't, there's a wall in the way.

on Jun 11, 2009

Yeah, the computational power needed to constantly update complex line of sight will bring any non-squad based game down to its knees. Something like DoW2 can probably do it because there are few units at any one time, but if you tried to do it on SupCom? Teehee.

Battleforge PvP actually has no fog of war. The players see the whole map.

on Jun 11, 2009

True enough with sup com, I have it love it and it will still bring my system weeping to its knees if I enable range finder etc,   but then again with the rate at which pc's are evolving what is to stop this from happening, in all seriousness most computer games these days need more GPU power than CPU.

Not being a programmer does tend to restrict my knowledge of what can and can't be done, the problem I have is I have never seen it attempted in any of the mainstream RTS games, it seems to be fog of war and thats it.

on Jun 11, 2009

I think the explanation is far more simple-- in the early days of RTS games, either the PCs were too weak or the programmers too lazy to make super large maps.  The maps tended to be small and cramped, so if they wanted things to-scale then they had two choices:

1) make the individual units incredibly tiny (which would negate the programming benefits of having smaller maps)


2) let any individual unit be able to see from one side of the map to the other if placed intelligently

They chose option 3) limit the LoS of units to around the size of an average monitor, so that your unit can't see the entire freakin' map at once

Since then, maps have started getting larger, but the FoW and LoS concepts were already in place, and people just started expecting them and getting used to them, even though they were completely contrived.

Also, stop complaining about Sup Com.  Just build a decent radar installation.  Much easier.

on Jun 11, 2009

Fallout: Tactics had a very good line of sight mechanic. For example, if you stood behind a pile of rocks, you'd be visible. If you went prone, you'd be hidden. There's no "radar" that magically detects people until you see them or they start shooting.

But, that wasn't an RTS

on Jun 11, 2009

World in Conflict does it very well. It does have fog of war, but it's determined logically. If your unit is behind a hill, building, or thick forest the enemy can't see it unless they're right on top of it. It's very useful for hiding AA to ambush choppers. Also, having a higher elevation gives tanks longer range, and as you said snipers have probably the longest range other than artillery.

on Jun 15, 2009

There are a large number of virtual table tops for pen-n-paper RPGs that have this feature.  Granted, they don't do it in real time (mostly vision is recalculated after every move), but the algorythm is as simple as having terrain (and possibly units) blocking an invisible light source, and tieing vision and fog-reveal into the shape of the resulting blocked 'light sources'.  Of course, doing that on a battle field in real time might be a bit of a resource hog.... even running a VTT with too many light sources and 'blocking topologies' slowed down my 2 gigs and 2.5ghz dual core a bit ... could just be code inefficiency, though.

on Jun 15, 2009

You never played Total Annihilation then.  It had realistic fog of war with terrain that blocked LoS and weapons fire, plus weapons shot farther the higher they were placed.  And it did all this back in the mid 1990's.  Imagine SupCom, now imagine terrain actually having an effect on weapons and LoS, and different types of locomotion.  KBots were fragile and slow, but could climb mountains.  Vehicles were faster and tougher, but needed relatively flat ground to turn and move.  Aircraft were the fastest and could fly over anything, but they were expensive and fragile.  Ships were ships, and it had subs that needed torpedoes or depth charges to kill.

on Jun 15, 2009

Yeah, that's one of the things where SupCom was a major step backwards...


A good LOS system is not something impossible to do.  It's been done, people are just lazy or cringe at such scary concepts as having their archers outrange their view when walking through a forest.

on Jun 16, 2009

I'm certain that part of it (like FireWarriors in DoW having short LOS but incredible range) got to do with gamebalance. If the abovementioned FireWarriors (FW) could see as far as they can shoot then they would be overpowered....now you have to scout with a unit to be able to fire at full range.


It also sounds like the OP is ready to sacrifice gameplay for realistic LOS rules. Making gameplay worse because of realism can never be good.

on Jun 16, 2009

The average human can see car sized objects coming from kilometers away given good eyesight and good conditions yet in the majority of RTS games out there I barely feel as if my units can see more than 20 meters away

A lot of RTS games don't have a fielded area more than a mile[.6km] across or two-- Many things have to be scaled appropriately to prevent the player from shooting across the map at all times, which would result in negative fun for all players. Take Men of War for example... The Tiger tank was capable of shooting [and killing] at distances greater than the game engine renders-- There has to be reduction [in L.O.S.] for gameplay value- or the maps have to be absolutely HUGE.


on Jun 16, 2009

What's wrong with huge maps?  They're great fun.


I used to be a prominent scenario designer for Empire Earth and when you made a map, it was normally limited to a maximum size of 400 squares by 400 squares, but I found a glitch that made it possible for massive 800x400 maps.  Man, that was an epic game...

on Jun 17, 2009

What's wrong with huge maps?  They're great fun.

It's sooooo much fun to wait while your units crawl from one end of the map to another in real-time. For hours.

on Jun 17, 2009

Yeah, a realistic real time war game would fucking suck.  You just can't do anything but fudge the more insurmountable logistical matters.


Oh look, the USSR is attacking the USA!  This is so cool, the ICBM's will be here in the next couple hours!  I can start my counter attack and come back tomorrow to see how it's going.  I hope their land invasion doesn't get lost in Mexico, I'd hate to have to wait more than a couple days to start fighting them.

RA2, real life style.

on Jun 18, 2009

Actually, ICBM flight time is up to 30 minutes.

And SLBMs may hit targets in several minutes if missiles will be lauched with a low-apogee trajectory and submarine is near the shore. Accuracy will suck in that mode though, so it's ok only against cities or it may be detonated above enemy missile sites in hopes of destroying enemy ICBMs in their boost phase (accuracy is too low so to target hardened missile silos themselves).