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General Forums => Wishlist => Topic started by: boomerlu on October 21, 2009, 11:47:38 PM

Title: Realistic Gunsight Mechanism
Post by: boomerlu on October 21, 2009, 11:47:38 PM
I know this is probably low on the list of priorities... but...

As I understand it, real reflector gunsights had an image that "came from infinity". What this means in practical terms is that the gunsight image would not distort no matter how you displaced your head. This is true for AH up/down and left/right axes but not for the forward/back axis.

As it is now, the AH gunsight gets bigger or smaller depending on how far forward or back your head is. Again, from my understanding of the optics, this was not how it worked - the image would remain the same apparent size no matter if you moved your head forward or backward. The pilot could adjust the apparent size of the sight by turning a knob on the sight; this feature was used for calibration and/or ranging.

Thus my suggested changes are: 1) Eliminate the change in size of the gunsight picture when moving the pilot's head back and forth. 2) Add commands to change the apparent size of the gunsight to enable proper calibration.

I have no real documentation, but I assume that HTC has the specs that demonstrate this, so it should only be a matter of implementation.

While this started as a realism gripe, here are some pros/cons

Pros
1) Adjusting head position will no longer affect the sight picture which means you can see all your instruments AND judge lead properly from the gunsight - no compromise on calibration.
2) Similarly, if you want to move your head forward to remove obstructions from view, such a movement would no longer alter the sight picture.
3) This has good synergy with TrackIR for the two above mentioned reasons.
4) This has good synergy with VR and stereoscopic gaming applications for the same two reasons. Note, this would also require the stereoscopic image feed the same gunsight picture to each eye, lest we see double gunsights (this was mentioned as a gripe in another wishlist thread).
5) REALISM! :D

Consider this an investment in time, as VR technology gets cheaper and more accessible, more people will appreciate this and the forethought of solving the double-gunsights problem.

Cons
1) Takes time to implement.
2) Not everybody will appreciate it.
3) Two new commands needed to adjust gunsight size.

I'm not sure on Con 1, it seems like a pretty simple thing to code.
Title: Re: Realistic Gunsight Mechanism
Post by: Saxman on October 22, 2009, 12:14:05 AM
boomer,

A lot of it depended on the gun sight. In the case of the Mk.8 used by the USN/MC (F4Us, F6Fs, FM-2s) the sight was specifically calibrated so that an aircraft with a 30ft wingspan will fill the center ring (wingtip to wingtip) at 200yds and the outer ring at 100yds. AFAIK, the Mk.8 couldn't be adjusted for different wingspans. Incidentally, I tested this offline and if you use the full-sized Mk.8 sight (with the extended "cross," rather than just the rings) the Corsair's gunsight is exactly half the size it should be.

It SHOULD look something like this:

(http://saxman.xwlegacy.net/AcesHigh/SightTrouble/SightAdjusted.png)

While in-game it actually looks like the one on the right...

(http://saxman.xwlegacy.net/AcesHigh/Sights.png)

...which looks like this when using the Dora as a "yardstick" (just over 30ft wingspan):

(http://saxman.xwlegacy.net/AcesHigh/SightTrouble/DoraSight400.png)

Note the range counter is double what it should be based on the historical calibration of the sight (taken offline, so it's pretty reliably ranged at 400yds. I also used the .target to confirm).

Personally, I think ALL gunsights should be permanently set to the aircraft's historical sight and should NOT be changeable.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 12:29:53 AM
Saxman,

My main issue is the size changing with head movement.

Calibration is a secondary concern. However, considering that we have a multitude of custom gunsights and that such modification is fairly active, a calibration option would benefit those of us who make our own sights. I respect your opinion to leave it fixed, but the historical reality is that some gunsights/planes did allow for calibration.

Given the fact that our gunsights are pretty far from historical reality (because of high customizability) and the fact that some planes allowed adjustment, I'd say take the practical approach and allow calibration.

I wouldn't be opposed to complete historical accuracy, but I doubt HTC will remove customizability.
Title: Re: Realistic Gunsight Mechanism
Post by: Stoney on October 22, 2009, 12:37:24 AM
Boomerlu, changing the size of the "ring" was a function of the K-14 and its British equivalent.  That sight didn't come into use until very late in the war for U.S. aircraft.  Further, the function of changing the ring was to allow the gunsight to compute lead for the pilot--it was a dynamic device, in that the pilot could change the ring based on each individual target.  It wasn't something he set in the hangar, and then flew with for an entire flight.  If you go to the Wiki, and look up the P-47N POH, it has a pretty good description of how the K-14 worked.

We currently don't have a means (paraphrasing some things I've heard in other threads) in-game to be able to create a credible lead-computing gunsight.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 12:45:45 AM
Stoney, I assumed that since the K14 had it that it must have been more prevalent throughout the war, my mistake.

On the other hand, we do have the ability to change the size of the ring by moving up/back, but that is an unrealistic "feature".

Again, main gripe is the head movement thing. The calibration option is secondary.

However, consider the following. Let's assume no in-game calibration and realistic fixed gunsight size regardless of head position. Since we have customizable sights, anybody who wanted to calibrate their sight could simply edit it in a graphics program to get the proper calibration.

It's a barrier to doing the calibration, but the option is still there, and anybody who actually cared about calibration in the first place would gladly just edit their sight.

So if you wanted to truly remove calibration, you'd have to remove customizability, which is something I doubt HTC will do. OTOH, HTC could very well simply not implement in-game calibration as a matter of laziness and/or efficiency.

However, the pretense to historical accuracy is broken with the allowance of custom sights, so IMO, why not allow direct size adjustability?
Title: Re: Realistic Gunsight Mechanism
Post by: Stoney on October 22, 2009, 02:22:54 AM
On the other hand, we do have the ability to change the size of the ring by moving up/back, but that is an unrealistic "feature".

Actually, they stay the same size regardless of how you move the head position.  The mils represented by the sight never change, only how you perceive it getting "smaller" or "larger".
Title: Re: Realistic Gunsight Mechanism
Post by: OOZ662 on October 22, 2009, 02:53:04 AM
If we're all about head movement gripes in here, I'd like to submit the fact that the size of the propeller on screen stays the same as you move your head back and forth.

Get yourself a dry erase marker. Sit on the runway with your engine idling. Trace the arc of the top of the propeller on your screen. Then move your head forward and back. Everything else gets bigger/smaller, but the prop stays the same size. It's very strange going for a look over the nose for landing and suddenly having a toy propeller on my 4hog. :D
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 03:05:39 AM
The mils represented by the sight never change, only how you perceive it getting "smaller" or "larger".
Sorry, one of your statements must be true, and the other must be false by geometry. You have to realize that "mils" represents an angle the sight covers, which in turn must be measured from a fixed point of reference i.e., the pilot's head position. If you move your head forward/backward and the perceived size of the sight changes, then the angle it represents changes dramatically (leading to inaccurate ranging). On the other hand, if the apparent size does not change, then the measured angle cannot change either.

These two facts are mutually exclusive, you cannot have both. I can draw you a picture if it's necessary. Which one of these facts is true, I'm not 100% sure about, but again, as I understand reflector sights, it should not change. This is because the sight projects an image which is supposed to "come from infinity". As an example, if you look at a small point that's very far away, for example a star or the sun, (which approximates an image coming from infinity), its apparent size and orientation will not change noticeably no matter how you move your head/distort your body.

To reiterate, the way the reflector sight functions is that it shows you a gunsight image which comes from "a gazillion miles away" so that no matter how you displace your head (forward/back, left/right, up/down), the orientation of the gunsight image will not change (i.e., the image will not appear to rotate obliquley).

As evidence that this is how it really worked, AH models up/down and left/right movement as not changing the orientation of the gunsight image which is only possible if the projected image "comes from infinity". As I understand it, this aspect at least is historically/realistically accurate.

As more evidence, since gunsights were used for ranging in a historical context, pilot forward/back head movement should not change the apparent size of the sight or this could lead to incredibly inaccurate ranging. With the head movement distances allowed by AH (which we treat as realistic), the range indicated could vary from 50%-200% of the true range AT LEAST and probably over a much larger range at worst (ie in planes like the Zero).
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 03:11:12 AM
If we're all about head movement gripes in here, I'd like to submit the fact that the size of the propeller on screen stays the same as you move your head back and forth.

Get yourself a dry erase marker. Sit on the runway with your engine idling. Trace the arc of the top of the propeller on your screen. Then move your head forward and back. Everything else gets bigger/smaller, but the prop stays the same size. It's very strange going for a look over the nose for landing and suddenly having a toy propeller on my 4hog. :D
While I got your humor and had a laugh, this is false in relation to the game. I tested it to make absolutely sure (I wouldn't be a good scientist if I didn't); the propeller arc does get bigger/smaller, just less drastically than the rest of the cockpit. The change in the apparent size is accurate for how far away the propeller is from the viewpoint versus how far away the cockpit structures are.

And besides, why are you deadstick landing a 4hog (besides battle damage)? Turn that engine on, just keep the throttle down... :neener:
Title: Re: Realistic Gunsight Mechanism
Post by: OOZ662 on October 22, 2009, 03:17:50 AM
Well, I suppose it gets about 15 pixels bigger. (http://i236.photobucket.com/albums/ff255/OOZ662/rolleyes.gif) Doesn't seem at all in scale, though.

Also, I don't remember the last time I was deadstick in a 4hog...generally I'm either entirely intact or popped out of the air due to the "OMFG PRK PLAIN" bumrush.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 03:27:16 AM
I meant why do you turn the engine off? Just keep it on but all the way throttled back.

As for the size diff - remember the Hogs were known for having a longer distance from the cockpit to the front of the nose than most other planes so the size difference from moving is especially small for the Hogs.
Title: Re: Realistic Gunsight Mechanism
Post by: OOZ662 on October 22, 2009, 03:31:08 AM
It applies to all aircraft. I actually first noticed it in a P-51 and have been grumbling about it for years. I emailed them but Skuzzy couldn't figure out what I was describing.

I meant why do you turn the engine off?
engine idling
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 03:36:31 AM
*Shrug*. I haven't done the math, but I'm pretty sure HTC wouldn't screw apparent propeller size up. As another test, record a film with engine off and move back and forth in the cockpit in the film viewer. Since the film viewer head movement isn't restricted to the cockpit, you'll be able to move through the front. You'll see there's no problem with the size, it should be accurate.
Title: Re: Realistic Gunsight Mechanism
Post by: Anaxogoras on October 22, 2009, 06:08:16 AM
Boomer, I do understand what you're saying, and you may be right.  The reflector gunsights behave as you describe in Il-2, and I had wondered about the difference.

The first reply from saxman was a hijack over one of his pet peeves (sorry sax  ;) ).

Then stoney followed up with a non sequitur about the K14.

Are you frustrated yet?  Welcome to the AH bbs. :cheers:
Title: Re: Realistic Gunsight Mechanism
Post by: Saxman on October 22, 2009, 07:52:05 AM
Boomer, I do understand what you're saying, and you may be right.  The reflector gunsights behave as you describe in Il-2, and I had wondered about the difference.

The first reply from saxman was a hijack over one of his pet peeves (sorry sax  ;) ).

Then stoney followed up with a non sequitur about the K14.

Are you frustrated yet?  Welcome to the AH bbs. :cheers:

boomer was mentioning the lack of realism in gunsight mechanics, and while yeah, the Hog sights are a personal pet peeve they're the only ones I've REALLY done any research in to be familiar with just how inaccurate they are. I also know that other aircraft have the same problem: Gun sight rings were often calibrated to a certain scale for ranging targets, and the way they're presented in-game makes them too small, I just don't have the numbers on the others. It's a realism issue I'd like to see addressed--along with allowing late sights like the K-14 to be adjusted in-flight--and I used the F4U as a specific example because it's the one I have.

And I don't think Stoney's post was off topic, because he brought up the specific point that the adjustable gunsights like the K-14 were a very late introduction, so very few actually worked the way boomer was thinking (which was the point of my post, in that some sights had a fixed calibration for ranging).
Title: Re: Realistic Gunsight Mechanism
Post by: GuyNoir on October 22, 2009, 08:20:15 AM
The reason why the gunsight gets bigger and smaller when you move your head forward and backward is the same reason that I gave in my '3d stereoscopic' thread:  the gunsight is actually on the same plane as the glass.  It's hard to tell since you probably play the game in 2d, but if you fly with 3d glasses, you'll see that you either have to focus your eyes on the gunsight, or you have to focus on the enemy out in front of you.  If it's the latter, you'll see two gunsights on either side of him...

Hopefully you can convince HTC to fix your problem, boomerlu, because it's also my 3d problem!  :D
Title: Re: Realistic Gunsight Mechanism
Post by: Stoney on October 22, 2009, 09:01:54 AM
Sorry, one of your statements must be true, and the other must be false by geometry. You have to realize that "mils" represents an angle the sight covers, which in turn must be measured from a fixed point of reference i.e., the pilot's head position.

No, the mils are measured from the sight.  I"m not arguing that there's not some 2D graphical issue here--merely trying to counter some of what you've posited about the sights so far.

Also @ BnZ:  Really?  I had to look up what that meant.  I'm still trying to figure out how, when he brought up the "adjustable ring on the site", it was skewed logic on my part to describe the mechanics of the K-14.
Title: Re: Realistic Gunsight Mechanism
Post by: Baumer on October 22, 2009, 12:46:22 PM
I thought this might be helpful, it's from the 1st edition of the fighter gunnery manual.

(http://332nd.org/dogs/baumer/BBS%20Stuff/gunnery1.jpg)

(http://332nd.org/dogs/baumer/BBS%20Stuff/gunnery2.jpg)

(http://332nd.org/dogs/baumer/BBS%20Stuff/gunnery3.jpg)

(http://332nd.org/dogs/baumer/BBS%20Stuff/Gunnery4.jpg)
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 02:10:00 PM
I thought this might be helpful, it's from the 1st edition of the fighter gunnery manual.
Thanks Baumer! This confirms what I've thought all along.
No, the mils are measured from the sight.  I"m not arguing that there's not some 2D graphical issue here--merely trying to counter some of what you've posited about the sights so far.
Sorry, this is still wrong. It is not a 2D graphical issue, but a matter of geometry. A Mil is a measure of angle, and again, the angle must be measured from some point of reference. In our case, it's our head. When you move an object closer to your head, it appears to get larger because it now covers more ANGLES in your visual space. I guess a picture will explain best. This is meant as a top-down view.

(http://i947.photobucket.com/albums/ad316/boomerlu/gunsightpic.jpg)

To reiterate, if the mils change with head movement, then the gunsight apparent size must also change. If the mils do not change with head movement, then the gunsight apparent size cannot change. I'm not sure why you are trying to say otherwise, I hope I've made it absolutely clear in my picture. Which of the two possibilities is historically accurate, I'm not sure, but again my understanding is that the MILS DO NOT CHANGE and therefore by geometry, the apparent size cannot change either. What Baumer posted only reinforces my position.

Boomer, I do understand what you're saying, and you may be right.  The reflector gunsights behave as you describe in Il-2, and I had wondered about the difference.

The first reply from saxman was a hijack over one of his pet peeves (sorry sax  ;) ).
Gav, glad to see an entire other company agrees with me. :lol

No problem from sax, he mentioned a legitimate point for us to consider. I countered with the facts of the game, i.e., customizable gunsights would spoil the "forced historically accurate" fixed gunsight size. I don't disagree with him, just mentioning a reason I don't think it would happen.

Then stoney followed up with a non sequitur about the K14.

Are you frustrated yet?  Welcome to the AH bbs. :cheers:
Actually, gav, it made sense for him to bring up the K14 issue with respect to sight size adjustment/calibration. I was in error to believe that adjustability was more widespread in WWII reflector sights.

With all due respect Stoney, what's been frustrating is your statements afterwards about mils and apparent size. Again, they are simply not true, and it's not a matter of opinion or historical accuracy, it's a matter of geometric/mathematical fact.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 02:21:06 PM
The reason why the gunsight gets bigger and smaller when you move your head forward and backward is the same reason that I gave in my '3d stereoscopic' thread:  the gunsight is actually on the same plane as the glass.  It's hard to tell since you probably play the game in 2d, but if you fly with 3d glasses, you'll see that you either have to focus your eyes on the gunsight, or you have to focus on the enemy out in front of you.  If it's the latter, you'll see two gunsights on either side of him...

Hopefully you can convince HTC to fix your problem, boomerlu, because it's also my 3d problem!  :D
Yup, your thread is what got me thinking about the geometry of the problem in the first place. :aok

The gunsight image is supposed to be perceived as "infinitely far away", not "on the glass". As it is, HTC models 2/3 of it properly.
Title: Re: Realistic Gunsight Mechanism
Post by: TnDep on October 22, 2009, 02:27:38 PM
 :salute you guys in deep thought including bloomerlu.  I need a nap after reading this forum  :banana:

boomer was mentioning the lack of realism in gunsight mechanics, and while yeah, the Hog sights are a personal pet peeve they're the only ones I've REALLY done any research in to be familiar with just how inaccurate they are. I also know that other aircraft have the same problem: Gun sight rings were often calibrated to a certain scale for ranging targets, and the way they're presented in-game makes them too small, I just don't have the numbers on the others. It's a realism issue I'd like to see addressed--along with allowing late sights like the K-14 to be adjusted in-flight--and I used the F4U as a specific example because it's the one I have.

And I don't think Stoney's post was off topic, because he brought up the specific point that the adjustable gunsights like the K-14 were a very late introduction, so very few actually worked the way boomer was thinking (which was the point of my post, in that some sights had a fixed calibration for ranging).
Title: Re: Realistic Gunsight Mechanism
Post by: Stoney on October 22, 2009, 03:37:33 PM

With all due respect Stoney, what's been frustrating is your statements afterwards about mils and apparent size. Again, they are simply not true, and it's not a matter of opinion or historical accuracy, it's a matter of geometric/mathematical fact.

Well then, I've apparently misunderstood exactly what it is you're getting at then.  I know what a mil is.  I've adjusted artillery fire before and I understand the math.  Are you saying that the span of mils increases if you move your head away from the sight, or that the number of mils stays the same?  Originally, you were talking about adjusting the size of the ring to compensate for changing the head position in the cockpit, right?  The size of the ring should represent the same number of mils, regardless of head position within the cockpit.  Perhaps I haven't made myself clear. Sorry, I'll just observe from here on out.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 03:45:37 PM
Ok, now that we've established it's a miscommunication problem, let me describe the situation and proposal:

1) Currently in AH, as we move our heads forward/backwards from the gunsight, the apparent size changes, i.e., the span in mils changes.

2) The first and main part of what I'm proposing is to eliminate that size change. Based on everything I've seen on how reflector gunsights work (including Baumer's post), the apparent size (i.e., how many mils it takes up on screen) should not change if you move your head backwards or forward. Therefore, I'm saying that the view/gunsight system should be adjusted so the gunsight image looks exactly the same no matter how far forward or backwards the pilot's head is.

3) "Calibration" or adjusting the size of the gunsight without head movement (ie via some keyboard command) is something I suggested to
a) Duplicate the behavior of what I thought were quite a number of historical gunsights (but as you mentioned, very few actually could be adjusted).
b) Allow AHers who make custom gunsights a practical tool for their calculations.

Hopefully we're clear now?
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 04:01:33 PM
The size of the ring should represent the same number of mils, regardless of head position within the cockpit. Perhaps I haven't made myself clear. Sorry, I'll just observe from here on out.
Right, but since the apparent size of the ring changes in AH when the head position in cockpit changes, so do the mils. This is the problem I'm suggesting we correct.

No need to bug out, any input you have is appreciated. The only frustration came from what I thought was your misunderstanding of the math behind the angle measures. Since I assumed you've messed with head positions and seen that the apparent size (and thus # of mils spanned) changes with back/forth head position, the only possible explanation was that you missed the math somehow.
Title: Re: Realistic Gunsight Mechanism
Post by: Baumer on October 22, 2009, 04:06:28 PM
Well you can all ready do 3B, I have made many custom sights for different aircraft and ordinance systems in the game.

I'm not sure that 2 is feasible with how the game graphics work on a traditional 2D system, the folks at HTC would have to comment on how piratical that really is. It will need to be address if HTC is planning to support the 3D systems mentioned in the other thread.

BTW you can perform the number 3 "calibration" off-line just switch to Knights and fly behind the circling drones and you'll get a very good film to work with. It's easy to look up the wingspan of the B-24, P-38, P-51 and 190D-9 for comparison.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 04:15:58 PM
Well you can all ready do 3B, I have made many custom sights for different aircraft and ordinance systems in the game.

BTW you can perform the number 3 "calibration" off-line just switch to Knights and fly behind the circling drones and you'll get a very good film to work with. It's easy to look up the wingspan of the B-24, P-38, P-51 and 190D-9 for comparison.
Yes, I know how to do this, however, it requires either head movement or trial-and-error editing of the gunsight.

Also, (3) is mainly meant as a supplement to (2), as with (2), our current system of using head movement to calibrate would no longer work.
Title: Re: Realistic Gunsight Mechanism
Post by: Baumer on October 22, 2009, 04:38:20 PM
I guess, like Stoney, I must misunderstand what you mean. I don't have to move my head to "calibrate" my sights. I usually fly whatever I'm working on "film everything" then take screen shots at specific intervals to get the sight picture I'm looking for. There is some iterative work but it's not overly problematic or difficult.


In my opinion it's overly easy to hit targets as it is, your request would make it even easier. The primary reason I'd support HTC putting effort into this would be to support 3D systems, there should be no reason to have to focus near and far with a reflecting sight.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 04:42:22 PM
Oh, I guess as far as calibration, that's one possible way to calibrate your gunsight - trial and error using screenshots. On the other hand, you can move your head position to accomplish the goal as well.

The method I use to... for example... design a gunsight on one airplane, and then adapt it to another. Say I designed a gunsight and I calibrated my angles/pixels ratio with the .target. Say I have a ring that matches the second circle on the .target at range 125.

Then if I wanted to use the same sight for another airplane, I would then include an instruction to "Match the calibration ring to the 2nd circle on a .target 125 by moving your head forward/backward in the cockpit."

That's one method of calibration and I think I read it in one of Andy Bush's articles at SimHQ.

By removing the change in gunsight image size with head position (as suggested by [2] which would have a side effect of helping 3d systems), you would also remove the head movement method of calibration. So I suggested as a practical matter to introduce a system in-game to accomplish the same thing without having to tweak the sight using a graphics program.
Title: Re: Realistic Gunsight Mechanism
Post by: Saxman on October 22, 2009, 04:48:35 PM

Then if I wanted to use the same sight for another airplane, I would then include an instruction to "Match the calibration ring to the 2nd circle on a .target 125 by moving your head forward/backward in the cockpit."


The problem there is several aircraft that have gunsights that are just too small for this to work reliably. You end up with the view set so far forward it's useless for anything else.

They REALLY need to fix the gunsight sizes on a number of aircraft.
Title: Re: Realistic Gunsight Mechanism
Post by: boomerlu on October 22, 2009, 04:52:12 PM
The problem there is several aircraft that have gunsights that are just too small for this to work reliably. You end up with the view set so far forward it's useless for anything else.

They REALLY need to fix the gunsight sizes on a number of aircraft.
True, just bringing up one method.