Current LoS and how it calculates has an inherent problem

[Thepaperclipkiller]

Let me preface that this is all coming from someone who plays only 5e on FG, I do not know if other games handle sight differently.

As far as I can tell, LoS calculates based off of the center point of the creature. That's actually a problem for LoS. Creatures of a larger size see just as much as creatures of a smaller size. It also creates the issue of not seeing a square fully based on LoS but if you use pointers you should actually be able to see a square just fine and be able to target them. I've included some screenshots to illustrate what I mean. I used a Hill Giant (Huge creature) and a PC (Medium Creature) to illustrate how this negatively affects Large-Gargantuan Creatures. I only used Medium and Huge for the ease of comparison, but it is even worse with Gargantuan.

The 1st pic depicts a Huge creature and what they can see at the moment.

The 2nd pic depicts a Medium creature standing in the center square of where the Huge creature was, showing from there they see the same as them.

The 3rd pic depicts a Medium creature standing in the lower left square of where the Huge creature was, which should depict what the Huge creature was also able to see. This shows the Huge creature should be able to see what is around the corner, however with how LoS is used right now it would not be able to see it on the map.

The 4th pic depicts the Huge creatures sight through a 5ft door. This really shows how the center point based vision creates issues.


To be honest, I do not know the amount of work it would take to change LoS. I believe LoS should be based on the entirety of the square, and not just the center point. Center point based is inaccurate and cripples the capabilities of larger creatures, especially Huge and Gargantuan. I wanted to bring this up while FGU is in the Beta stage before LoS is considered mostly complete. I want LoS to be the best feature it can be. It's the big selling point for FGU in my opinion. As it stands right now with how it is center point based, I don't think I would even use it in my games because of it. If I had FGC and didn't have FGU already, I wouldn't upgrade simply because the LoS not working accurately compared to how the game handles sight in 5e. A way I could see it potentially working is you base sight off of each point on a square of the creature. I believe each square on a grid has 9 points, 8 on the outside and one on the inside. You could get away with not using the center point if you used the outside 8 points.

I want this product to be the best it can be, and I know everyone in the forums do as well. Please change LoS at some point to be based on the entirety of the square. I know that is going to be a lot of work and I wouldn't expect something like that for months. But please consider it.

[Paperclipkiller]

I just realized I logged into my account from when I tried out Fantasy Grounds waaaaaaay back in the day to post this and I didn't know what I was doing in regards to Subscriptions/Buying. Chrome auto completes the login for both and it keeps slipping my mind to delete that auto complete from my history. Oops! This is my actual account, I swear! Will delete the auto complete now for sure.

[EnragedLlama]

Other than being able to see through the door, I don't appear to see an issue with how LOS is handled here? Just like with nearly every game, your LOS is from a pinpoint location somewhere on your character. Your arms don't have eyes and your feet don't have eyes. Just because a character commands the "space" of a 5' square or larger, doesn't exactly mean they have some weird mutant omni-vision whos primary vision is located from every exact location of the 5' square. If something like this was to be attempted then the argument must be made if a creature is inside of the 5', on top of the 5' Or if they're on the outer edge of the 5'. This sort of criteria would be horrific to code, let alone manage in a game setting.

[Paperclipkiller]

Other than being able to see through the door, I don't appear to see an issue with how LOS is handled here? Just like with nearly every game, your LOS is from a pinpoint location somewhere on your character. Your arms don't have eyes and your feet don't have eyes. Just because a character commands the "space" of a 5' square or larger, doesn't exactly mean they have some weird mutant omni-vision whos primary vision is located from every exact location of the 5' square. If something like this was to be attempted then the argument must be made if a creature is inside of the 5', on top of the 5' Or if they're on the outer edge of the 5'. This sort of criteria would be horrific to code, let alone manage in a game setting.

Targeting in 5e is based on the corners of the square. A creature with the current LoS could potentially not see a target in a square due to the LoS mask, but should able to see it based on how targeting works.

[EnragedLlama]

If you walk up to a wall and stick your face against it near a corner. People will see roughly half of your body and all you are going to see is wall. in RPGs this is referred to as large hit-boxing, in FPS's this is referred to as 'Close Cornering'. Despite your face being against the wall and seeing nothing but wall. that doesn't prevent everyone else from blowing that half of your body into bits. Or swordsman from chopping those bits off. This isn't the children's game that gets played where you put your hand over your eyes "if i cant see you, you cant see me!". This logic doesn't work in a game or in real life... I mean maybe if something is a 5x5 gelatinous cube? I don't even know if those things have eyes...

Additionally, You have to see something to target something (usually) But just because you can see and target something, doesnt mean they have to see you in return. Otherwise things like backstab or Invis would be fairly moot.

[Paperclipkiller]

That is not how the rules of 5e work however. If your square can be seen, you can be targeted. This is covered by the various rules of cover like half cover and 3/4 cover. DM interpretation aside for how they might allow certain things, that is RAW and RAI and should be applied for how LoS as well. In fact especially with LoS. If LoS doesn't follow the RAW for how sight works in 5e, it isn't working correctly. The 5e designers have also said you are considered to be looking in every direction when in your square.

Thankfully, FG has an option for "facing" in their options if you want to use that in your game. It is under the "Token (GM)" options in Options while in a game. If you want that to be included in your game, great! However it is not how the base game is run.

[EnragedLlama]

You nailed that first sentence correctly! "If your square can be seen, you can be targeted." But that isnt your issue here. Your issue with your Line of sight not being a 15 foot cubed omni-present all-seeing eyeball that is somehow detached from your character, that simultaneously is in every position within your 15' cube at all times.

You are not applying even your own stated rules here. Yes. If your square can be seen. You can be Targeted. That has nothing to do with if you can see the one targeting you. Your argument is that you should be able to see them in return which is just flat out false and has no baring within FG, or 5e. And you are correct, you can be "looking in every direction when in your square" But that has nothing to do with your 5' square having eyes in every orientation from every position within that square. Your eyes are assumed fixed roughly in the middle of that square unless stated otherwise and this should be handled on a case-by-case with your DM.

[ddavison]

Hello Paperclipkiller,

Your interpretation matches the rules as written for 5E and for many of the other editions of D&D. We will discuss this internally to collect some thoughts on it and get back with you.

[EnragedLlama]

Hello Paperclipkiller,

Your interpretation matches the rules as written for 5E and for many of the other editions of D&D. We will discuss this internally to collect some thoughts on it and get back with you.

Mind quoting or pointing me in the direction of the RAW or RAI rule you are stating that allows a players vision to be located away from the players body and arbitrarily positioned within a players square?

[Paperclipkiller]

Line of Sight is based off of corners in 5e. Page 251 of the Dungeon Masters Guide, under the section labeled "Line of Sight".

"To precisely determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If at least one such line doesn't pass through or touch an object or effect that blocks vision-such as a stone wall, a thick curtain, or a dense cloud of fog-then there is line of sight"

I suggested putting a LoS indicater in center of lines as well as corners in my original post because some doors stick out into squares a bit on battlemaps which are not considered when determining LoS in the DMG. And you'd want players to actually be able to see through doors.

[EnragedLlama]

Well hell, Apologies then.. i expected basic common sense to apply here. I cant wait to explain to my DM that despite my character registering as Small and only 2' tall. that its completely irrelevant and i can see everything perfectly fine as if i was 5 ft tall as thats my controlled area for no apparent reason... yay.

Thats going to be pretty traumatizing to our 7'11'' ally that cant see over anything due to his controlled space only being 5'.

[Paperclipkiller]

Technically you'd see the same as if you were say 30ft tall if you were still a Medium creature. It's one of the things you just gotta deal with in regards to token based games, even if it's not "realistic". That does lead to situations of "that doesn't make sense", and maybe the DM rules it differently as a result. Your DM is not wrong in their ruling if they want to rule it that way either, as the DM can change the rules of they want.


@ddavison - Thanks for letting me know Doug! Apologies if I came off harsh on my post. You guys have honestly been doing great work so far, and it's been fun learning new things while making LoS maps.

[LordEntrails]

One thing to remember, tokens, or characters, are not stationary within their squares. They are assumed to be moving about within their square, or at least they are allowed to do so without any interference.So, a character could move their head to each of the four corners of their controlled area during a round. Hence why it "makes sense" (to some degree) that line of sight is drawn from each square.

But also note, LOS rules make no attempt to adjudicate for height. And, I suggest you query your DM, never tell them what the rules say, since they can make any ruling they want (and hopefully they do so to maintain the enjoyment of all).
:)

[EnragedLlama]

I just find it astounding that common sense has to be an alternative DM ruling outside of the book is all. Ive never seen this before so its a bit baffling.

[EnragedLlama]

One thing to remember, tokens, or characters, are not stationary within their squares. They are assumed to be moving about within their square, or at least they are allowed to do so without any interference.So, a character could move their head to each of the four corners of their controlled area during a round. Hence why it "makes sense" (to some degree) that line of sight is drawn from each square.

But also note, LOS rules make no attempt to adjudicate for height. And, I suggest you query your DM, never tell them what the rules say, since they can make any ruling they want (and hopefully they do so to maintain the enjoyment of all).
:)

While i agree they can freely move about, but with that ruling it is just assumed that everyones heads are everywhere. This seems exceptionally counter intuitive to a game that tries to encourage roleplay while maintaining a fine line of realism.

Additionally, your controlled space is 5' squared. The same assumption being made that characters are able to have their eyes at any portion of that controlled space can be made to assume that height follows the same squared ruling as that is your only portion of controlled space. Which is why when you assume things like character vision instead of a fixed location. Games quickly go off the wall.

[LordEntrails]

While i agree they can freely move about, but with that ruling it is just assumed that everyones heads are everywhere. This seems exceptionally counter intuitive to a game that tries to encourage roleplay while maintaining a fine line of realism.

Additionally, your controlled space is 5' squared. The same assumption being made that characters are able to have their eyes at any portion of that controlled space can be made to assume that height follows the same squared ruling as that is your only portion of controlled space. Which is why when you assume things like character vision instead of a fixed location. Games quickly go off the wall.
*shrugs*

But without such a rule, how would you peak around a corner? Because physically I could walk up to a corner and just peak around and see close to 90 degrees. But, if my LOS was only from the center of my square, then I couldn't see anywhere close to along the wall (only 45 degrees). So in that case, which is more "real"?

As for games going off the wall, been using these, or similar LOS rules for 30? years, never had a problem :)

[EnragedLlama]

*shrugs*

But without such a rule, how would you peak around a corner? Because physically I could walk up to a corner and just peak around and see close to 90 degrees. But, if my LOS was only from the center of my square, then I couldn't see anywhere close to along the wall (only 45 degrees). So in that case, which is more "real"?

As for games going off the wall, been using these, or similar LOS rules for 30? years, never had a problem :)

What games are you playing that you have complete 180 vision in? Also i never stated that it needed to be retained at 45 degrees, I wouldnt even be apposed to it be widened to air force standards of 147 degree or as low as clear vision standard of 40 degree.

[Paperclipkiller]

In the land of creatures who range from humanoid to monstrosities, to beings made of only fire, I think our idea of "standard" for vision may not work ;)

[LordEntrails]

What games are you playing that you have complete 180 vision in? Also i never stated that it needed to be retained at 45 degrees, I wouldnt even be apposed to it be widened to air force standards of 147 degree or as low as clear vision standard of 40 degree.
D&D, and actually is 360 degrees, not 180 :)

And actually it really doesn't matter what I do or what happens at my tables. Everyone there is happy with what happens including how we resolve LOS. What matters at your table is that everyone is in agreement and having fun :)

As for using the USAF standard, that doesn't apply to D&D. The Air Force assumes a pilot is stationary in a fixed sitting position with limited head movement. That is nothing like a combat standing, moving, dodging, swinging and doing whatever you have to do to be situationally aware. (Sure, you shouldn't be 360 degree aware, but doesn't matter to my game(s).)

[Neovirtus]

I think as far as implementation of the RAW goes, the software could calculate LOS from each corner and simply have the visible area be additive between all 4 calculations.

Regarding some of the questions about the RAW interpretations of LOS... There is no instantaneous time increment in 5e (or any version of D&D). Your 5 ft square is the space you control (for 6 seconds at a time) and the idea that your vision is restricted to the center of your square is the *least realistic* possible interpretation I can you of, so that argument doesn't make a whole lot of sense to me. And as far as height goes... That's just not in the rules. Any ruling your DM makes to differentiate the way two medium sized creatures with different heights interact with the world is not RAW.

[Dtoad]

Wow. The current LoS rules won't affect my enjoyment of the game, but this degree of rules-lawyering certainly would. If you have to move a half-square to peek around a corner, so be it.

I do hope that in the future, after LoS ranges are limited appropriately, we also get some way to limit field of vision as well. I would require at least a free action to be used when players look behind them, and enjoy it immensely when they forget. :p

[Paperclipkiller]

I think as far as implementation of the RAW goes, the software could calculate LOS from each corner and simply have the visible area be additive between all 4 calculations.

Center of line points would need to be used as well. Otherwise 5ft corridors would be an issue. Thankfully FG has center of line points already on each square.

[Dtoad]

One thing that I have to remind myself is that FG is a virtual tabletop, and there is no sense in trying to turn it into a video game.

But that won't keep me from trying. :mad:;)

[Neovirtus]

Center of line points would need to be used as well. Otherwise 5ft corridors would be an issue. Thankfully FG has center of line points already on each square.

I don't think there should be any scenario where using corners would give less visibility than the center point method, as shown in the first example attached. The only scenario I could think of that might break that would be a less than 5 foot hallway, where the nearest corners are against the wall. In that case it looks like the two back corners' vision still covers the full "center point" line of sight.

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[Paperclipkiller]

I don't think there should be any scenario where using corners would give less visibility than the center point method, as shown in the first example attached. The only scenario I could think of that might break that would be a less than 5 foot hallway, where the nearest corners are against the wall. In that case it looks like the two back corners' vision still covers the full "center point" line of sight.

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Your example of a less then 5 foot hallway actually explains still why it's needed. Once you're in that hallway, your corners are unusuable for LoS but you should still be able to see in them.

From what I can guess, current LoS doesn't allow you to move your center point through occluders built. This is to prevent you from looking through walls when your square is partially in a wall. If they end up changing it to the points of the square on the outside, they are going to have to find a way to disable certain points whenever they go through said occluders. So the corner points may not be enabled while looking through a small hallway. Which is why the center points are needed, to make up for the fact the corner ones on the opposite side are disabled. My wording may not make sense, in which case let me know and I'll make a pic of what I mean when I get home.


EDIT: one way I can see how they may be able to enable turning on/off points in walls for example is having an additional setting for LoS. You click in a closed of section of Wall Occluders with this button and it makes the entire section turn off points when they overlap with that section. I could see what I'm asking for in regards to LoS be a huge overhaul of it which is why I wouldn't expect something like that for months.

[Neovirtus]

Your example of a less then 5 foot hallway actually explains still why it's needed. Once you're in that hallway, your corners are unusuable for LoS but you should still be able to see in them.

Ah, good point, I have thought of that. I guess there are different ways to tackle that and we'll have to see what they come up with. I could envision them making LoS work off of corners, and movement blocking based on center. Then if the unit's square passes through a narrow channel they'd have to restrict the "square" for line of sight purposes. Maybe make the system think the square is one size category smaller or something for the purposes of calculations LoS. Will be interesting to see what they come up with.

[Paperclipkiller]

I've had some thoughts on how they could implement it but this is coming from a non-coder.

The big issue if they did outer square points for LoS, what about when they are partially in walls? They'd have to implement LoS for creature squares, where the center point looks to see if it can see the outer points. If it can't see the outer points because of a wall between them, those points get disabled. In regards to Large+ creatures, it would have to be a bit more complicated. The center point of all the squares overall would have to be calculated to see the center points of all the squares proper. If they aren't see, the surrounding points are disabled. And in regards to overlapping points of squares touching each other, they'd be enabled if one of the squares touching it can see it.

At least that's how I could see it working. Which would require an overhall by quite a bit. Regardless it's a complicated thing for sure.