Previous Thread
Next Thread
Print Thread
Rate This Thread
Hop To
#4304204 - 10/18/16 09:19 PM LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong?  
Joined: Jun 2010
Posts: 39
Victor1_9er Offline
Junior Member
Victor1_9er  Offline
Junior Member

Joined: Jun 2010
Posts: 39
New York
So out of curiosity I installed LB2 on my older windows 7 64-bit laptop to see if it would work -- and potentially with a notion to make a few FRAPS videos if it looked good. I have the LB2 Anthology CD's in storage, but have the 4 disks ripped to ISO's (Longbow Anthology is Longbow Gold FX + Longbow 2 already patched to v2.09F with the D3D Update). After LB2 Final database patch, dgVooDoo 1.50, Saitek HOTAS install, etc, etc, it works and looks good though I had to fix 2 issues.

I had to force LB2 to use my NVIDIA card instead of the integrated Intel chipset; and had a strange error in event viewer that was causing crashes related to DWM but that was fixed by checking 'Disable desktop composition' in the LB2 Compatibility tab. And it works, and is surprisingly stable. After maxing out AA Settings in the NVIDIA Control Panel and Running FRAPS at 60 FPS I could even capture great looking Lossless HD vids!

I solved the Low-Rotor RPM Stall permanently by capping the frame rate (using NVIDIA Inspector 1.9.7.3) to 43 FPS. This made the stall happen the correct amount and also solved the exagerated altitude dependant effects. What I couldn't fix (with FPS capping or CPU slow-down using CPU processor states & limiting CPU multipliers) was the HE rockets falling short.

Then I noticed something strange...

I wonder if the Rocket Accuracy problem is due to something other than the CPU speed. I observed that there is a buggy "range-to-target" value when switching between TADS and FCR. When activating the Laser in TADS the Range-to-target distance switches to meters, then when going back to FCR the distance is massively different (much more than I remember back in the Win98 days). The difference is usually around 200 meters! (See the pics below.) And at long range it can be as much as 500 meters different. In Windows 98 I distinctly remember those distances being close, but not exact. This was consistent with Laser targeting being the most accurate followed by FCR, followed by TADS triangulation. The game introduced a very minor fudge factor to show that FCR ranges weren't as good as Laser ranges.

But to be .5 km different, something just doesn't seem right.

Even more strange, is that when going from TADS Laser back to FCR, if the FCR sweep is not over the target, the Target Reticule drops and no longer sits over the target but to a place in front of the target (which is usually where the rockets land when they miss). When the target reticule drops the FCR range increases even though the spot on the ground in front of the target is actually closer. The distance should be decreasing, not increasing. Then once the FCR sweep passes over the target, the reticule returns to the correct spot and the range decreases -- exactly opposite of what it should be doing.

To check this, I compared other Glide Wrappers and tried different resolutions, as well as in software mode, and even on an old Vista machine. They all show this behavior, and of course the HE rockets all land prematurely short of their target. Too bad I don't have a Windows 98 machine around to see if these range-to-target values are normal. I'd love to know if anyone else can confirm this. Try it in Instant Action on a stationary target like a building. Even when I land right next to a building and target it, the distances between TADS and FCR can vary by as much as 15 meters -- that's crazy!

I wonder if the HE rockets landing short is due more to this possible range-to-target bug and only slightly related to the CPU being too fast. One hypothesis is that there is a bug in the range and targeting system on newer machines which is why the rockets miss. Is it caused by the Glide Wrappers, or some other part of the game which is incorrectly calculating distances? We may never know, but wouldn't it be great if this were solved?

~Victor1


Notice: TADS Laser Range-to-Target 5402 meters:





Notice: FCR Range-to-Target 5908 meters, 506 meters different than TADS Laser range:

That's 0.5 km difference and I can't imagine that is how the game is designed to work.




It gets even weirder, and I can't believe I never noticed this behavior until now.

Notice: TADS Laser Range-to-Target 95 meters:





Notice: FCR Range-to-Target 111 meters (TADS 95m), Target Reticule in front of target and yet range is greater:

When switching from TADS to FCR, the reticule moves off target and should be giving a shorter range, but instead gives a greater distance! Rockets usually fall short and land in this vicinity.





Notice: FCR Range-to-Target 107 meters:

Once an FCR sweep pics up the target, the reticule moves back onto the target, but the distance decreases and it is 9% different than what the TADS Laser shows at 95 meters.





Notice: Target Reticule in front of target between TADS to FCR switch:

Could this be why HE Rockets always fall short? Is the targeting system being fed incorrect distances?




And again...

Notice: TADS Laser Range-to-Target 1757 meters:





Notice: FCR Range-to-Target 1832 meters (TADS 1757m), Target Reticule in front of target and yet range is greater:





Notice: FCR Range-to-Target 1823 meters:

After an FCR sweep the reticule moves over the target and the distance is updated, though it's still 67 meters different than TADS.




One more...


Notice: TADS Laser Range-to-Target 264 meters:





Notice: FCR Range-to-Target 302 meters (TADS 264m), Target Reticule in front of target and yet range is greater:





Notice: FCR Range-to-Target 299 meters (TADS 264 meters):



AH-64D Longbow - Purchased in 1996
Longbow Gold - Purchased in 1997
Longbow Anthology - Purchased in 1998 (still have)
...Looking for the 'Ingress Point' to this,
my fav sim of all time!
Inline advert (2nd and 3rd post)

#4304867 - 10/20/16 06:56 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Nov 2006
Posts: 3,453
Flyboy Offline
Senior Member
Flyboy  Offline
Senior Member

Joined: Nov 2006
Posts: 3,453
England, UK
Hi Victor1_9er, I haven't posted on here in forever but your topic compelled me to jump in and answer. Sorry, buddy, but you could have saved yourself a lot of research and typing on this one...

I forget the details and all the correct terminology, but basically, locking onto a target in TADS mode and using the laser rangefinder gives you a more accurate range reading than when in FCR mode. This is a trait of the real thing, and therefore is a part of the sim. The FCR is a radar, which in one respect is a bit like GPS in that it gives you a rough range within, for argument's sake, 100 meters or so. TADS is an optical sight and when used with the laser rangefinder, gives you a much more accurate range reading to within, again for argument's sake, 1 meter. Also note how a target's range changes even when in TADS mode, but when you turn the laser rangefinder on and off.

You should only ever use rockets in TADS mode, as the laser rangefinder feeds more accurate range data to the fire control computer which elevate the rocket pods for you. Also, it's a sure-fire way of knowing that your rockets can actually have a chance of hitting their targets... as if you can't see them, you can't hit them. TADS is a line-of-sight targeting mode, where in FCR mode you can lock onto targets without even having seen them.

EDIT: I re-read your post and you acknowledge the range difference in the different targeting modes, and I think you're getting at something a bit different to what I addressed. All this is so confusing to me now! Possibly touching on something else, if I remember correctly, didn't the range to target change even if the laser rangefinder was on, but you switched between TADS and FCR modes? I think part of the problem is, the sim tried to correlate too much information... it tried to show you the range parameters for two sensors in one cockpit, in one view. What I'm trying to say is, in real-life the co-pilot/gunner would have his range to target up in TADS mode using the laser rangefinder, and the pilot would have his range to target up in FCR mode. There would be a difference between the two ranges. Neither crew position would see the other's targeting data... it wouldn't merge and try to show data from two different sensors giving two different range readings, therefore causing an anomaly. I don't think. You see this is why I love the Comanche, all sensors work together without the crew members having to manually switch between them all the time. Sensor fusion baby!

#4305220 - 10/21/16 06:47 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Jun 2010
Posts: 39
Victor1_9er Offline
Junior Member
Victor1_9er  Offline
Junior Member

Joined: Jun 2010
Posts: 39
New York
Hey Flyboy, thanks for responding! Your right and I agree with everything you are saying.

I played this game so much in years past that I have a good handle on the difference between FCR and TADS Laser ranges. I even have my old LB2 manual that if necessary I can look at. I completely agree with you about FCR giving an approximation of range and TADS being a visual line-of-sight system. I've always switched to TADS and turned-on laser right before going to guns on a target because of the better accuracy. It's cool when you Lase a target that's moving and you can watch the range change in TADS, while in FCR it only updates as the radar sweeps over the target.

To boil down what I was getting at:

In the Windows 98 days, I don't remember the FCR range being THIS different from TADS. It seems nowadays that the difference between the two ranges is greater than what I remember. In other words, back-in-the-day a target 5000 meters away in TADS, would be 4900-5100 (+/- 100 m) in FCR -- not hugely different. I'm giving an estimate here. But I'm getting differences much greater and it's always an increase in distance when switching to FCR never a decrease. I need someone on a Windows 98 machine to "check" the range differences to see how much different they are. I wish I could check myself, but I don't have a monitor that I can hook my old Win98 machine to. I have memories of the FCR range being inaccurate but not by as much as now -- though in fairness I could be wrong.

On a Win98 machine are range differences between TADS and FCR as great as .5 KM? That's what I'd like to know.

I could be grabbing at straws here, I fully admit that. Truth is, I'm desperate to find a way to fix the rocket problem since on my system everything else is working flawlessly.


~Victor1_9er


AH-64D Longbow - Purchased in 1996
Longbow Gold - Purchased in 1997
Longbow Anthology - Purchased in 1998 (still have)
...Looking for the 'Ingress Point' to this,
my fav sim of all time!
#4305315 - 10/22/16 12:24 AM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Dec 2000
Posts: 5,600
Recluse Offline
Mediocrity Above All!
Recluse  Offline
Mediocrity Above All!
Hotshot

Joined: Dec 2000
Posts: 5,600
Randolph, NJ
I still have a Win98 machine with LB2 loaded. If I get a chance to unpack it and set it up I will try to see if the TADS/FCR differential is different. That machine has a Voodoo 5 card in it, so should be a good LB2 reference machine for true 3DFX.


Long system spec sig follows:






PowerSpec G436
Lian Li ATX 205
MSI Z490 Plus Motherboard
Intel Core i7 10700K 3.8 GHz
32 GB RAM DDR4 1600
Nvidia RTX3070

Windows 10 Professional 64 Bit

Flight Gear:

Cougar Hotas S/N 26453
Thrustmaster RCS Rudder Pedals

#4305320 - 10/22/16 12:50 AM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Jun 2010
Posts: 39
Victor1_9er Offline
Junior Member
Victor1_9er  Offline
Junior Member

Joined: Jun 2010
Posts: 39
New York
Ah Recluse, that would be great!

I landed right next to a barn, the TADS/FCR differential was 15 meters! It makes no sense to me that the FCR range would be that different. And the FCR is never "less than" the TADS range. If FCR had a fudge factor added for inaccuracy it would sometimes be greater and sometimes less.

I'll def owe you one if you get that pup up and runnin!


AH-64D Longbow - Purchased in 1996
Longbow Gold - Purchased in 1997
Longbow Anthology - Purchased in 1998 (still have)
...Looking for the 'Ingress Point' to this,
my fav sim of all time!
#4307703 - 10/31/16 01:58 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: May 2010
Posts: 279
flightsimer90s Offline
Member
flightsimer90s  Offline
Member

Joined: May 2010
Posts: 279
It's your FPS. Limit it to 20-30 FPS and the game plays like it did

1. YAW WORKS
2. ROCKETS WORK
3. HELLFIRE COUNTDOWN TO IMPACT TIME WORKS
4. Kiowa, BlackHawk, LB, and Apache IS WAY MORE RESPONSIVE!
5. Other aspects of the game work better

So How do you do it?

NVIDIA:

1. go to nivida control panel and for the game set adaptive vsync to half-refresh rate, considering if you have a 60fps monitor it will lock to 30 fps

AMD:

1. download radeon pro, go to the tweaks menu, and from there you can set a 30hz refresh rate or a 30fps lock.

simple as that.

Last edited by john84; 10/31/16 02:37 PM.
#4308065 - 11/01/16 04:14 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Jun 2010
Posts: 39
Victor1_9er Offline
Junior Member
Victor1_9er  Offline
Junior Member

Joined: Jun 2010
Posts: 39
New York
Hi John84, yes your right that limiting FPS (I have an NVIDIA card) will fix the rockets, but here's the problem with that method: You will no longer get any Blade-Stall when running that slow. In the old days having a stall made flying a lot more technical and more realistic. At 30 FPS I can completely roll the chopper upside down and fall for hundreds of feet inverted and still once I turn back over, not experience a stall -- which of course is ridiculous.

Ideally you want to limit the frame rate to allow for some blade stall, usually when you descending at greater than 500-600 feet/min. On my machine that means capping the FPS at 42 FPS.

Also I'm not totally convinced that the rocket accuracy problem is completely related to Frame Rate or CPU speed, even though a few years ago using those methods on my Vista machine seemed to work (but no longer works on my on my Win7 64-bit dual core machine). My reasoning is that slowing down the machine fixes all the other too-fast problems, but doesn't fully fix the rocket problem unless you slow the FPS down to a nearly unplayable state. Why are the rockets different than the other too-fast problems?

And to my original point, why does the FCR-TADS differential seem wrong, as per my memory of the good 'ol days?

~Vic

BTW I can cap the FPS down with NVIDIA Inspector, but also with FRAPS, both work just as well.

Last edited by Victor1_9er; 11/01/16 04:22 PM.

AH-64D Longbow - Purchased in 1996
Longbow Gold - Purchased in 1997
Longbow Anthology - Purchased in 1998 (still have)
...Looking for the 'Ingress Point' to this,
my fav sim of all time!
#4308266 - 11/02/16 08:19 AM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: May 2010
Posts: 279
flightsimer90s Offline
Member
flightsimer90s  Offline
Member

Joined: May 2010
Posts: 279
Everything works for me in my method I experience blade stalls and lowered rpm once upright and after the maneuver.
pressing alt-o i have custom and everything checked for flight model and realism

PS if anyone is experiencing trouble minimizing lb2 you need to win windows key not alt-tab

Last edited by john84; 11/02/16 08:20 AM.
#4308358 - 11/02/16 05:09 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Jun 2010
Posts: 39
Victor1_9er Offline
Junior Member
Victor1_9er  Offline
Junior Member

Joined: Jun 2010
Posts: 39
New York
When you say blade stalls and lowered rpm, I'm wondering if you and I referring to the same thing. I can still get a low rpm warning from #%&*$# betty, but I'm talking about a catastrophic blade stall that you cannot recover from. In the windows 98 days, if you pulled up too hard at full speed you could get into a complete stall with no recovery possible even if you had several thousand feet altitude. The rotor blades would come to a complete standstill and you would fall out of the sky. Are you able to get "catastrophic" blade stalls at 30 FPS?

I'm not able to get catastrophic blade stalls until my FPS is over 35.
On my system:

Frame
Rate vs Blade Stall

30 Impossible
31 Impossible
32 Impossible
33 Impossible
34 Impossible
35 >Max Descent
36 >Max Descent
37 >950-900 ft/min
38 >900-850 ft/min
39 >850-800 ft/min
40 >750-700 ft/min
41 >700-650 ft/min
42 >600-550 ft/min *Ideal*
43 >500-450 ft/min
44 >450-400 ft/min
45 >350-300 ft/min


AH-64D Longbow - Purchased in 1996
Longbow Gold - Purchased in 1997
Longbow Anthology - Purchased in 1998 (still have)
...Looking for the 'Ingress Point' to this,
my fav sim of all time!
#4641931 - 02/01/24 05:35 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Mar 2009
Posts: 38
FlyinJ Offline
Junior Member
FlyinJ  Offline
Junior Member

Joined: Mar 2009
Posts: 38
Originally Posted by Victor1_9er
When you say blade stalls and lowered rpm, I'm wondering if you and I referring to the same thing. I can still get a low rpm warning from #%&*$# betty, but I'm talking about a catastrophic blade stall that you cannot recover from. In the windows 98 days, if you pulled up too hard at full speed you could get into a complete stall with no recovery possible even if you had several thousand feet altitude. The rotor blades would come to a complete standstill and you would fall out of the sky. Are you able to get "catastrophic" blade stalls at 30 FPS?

I'm not able to get catastrophic blade stalls until my FPS is over 35.
On my system:

Frame
Rate vs Blade Stall

30 Impossible
31 Impossible
32 Impossible
33 Impossible
34 Impossible
35 >Max Descent
36 >Max Descent
37 >950-900 ft/min
38 >900-850 ft/min
39 >850-800 ft/min
40 >750-700 ft/min
41 >700-650 ft/min
42 >600-550 ft/min *Ideal*
43 >500-450 ft/min
44 >450-400 ft/min
45 >350-300 ft/min


I finally got LB2 to run stable on my system and I've been testing frame rates vs blade stalls.

I'm playing using nGlide on Windows 10.

I found that if I play at the default 60 fps I get blade stalls very easily.

I used your guide, but even at 45 fps I never got blade stalls.

I just did a ton of testing and I found that you can never get blade stalls if your FPS is 58 or below. Setting the FPS to 59 finally gives you blade stalls, but at 58fps they never happen.

This is so bizarre. I can't really tell if the blade stalls happen at a lower ft/mn depending on the FPS being locked at 59 or 60. They seem almost identical, you'll get blade stalls very easily at 59 or 60, but at 58 or lower they just never happen.

Seeing how your tests were done over 8 years ago, I wonder if more modern systems have made it even harder to get a "sweet spot" for blade stalls.

Also I found that limiting my fps to 30 only slightly helped the rocket issue. Even dropping it down to 5 fps rockets still fell slightly short. However, they fall much more short at 60fps vs 30fps.

Last edited by FlyinJ; 02/01/24 05:37 PM.
#4642688 - 02/17/24 12:09 PM Re: LB2 Possible Reason HE Rockets Miss - Range-To-Target Wrong? [Re: Victor1_9er]  
Joined: Jun 2008
Posts: 100
Floydii Offline
Member
Floydii  Offline
Member

Joined: Jun 2008
Posts: 100
Australia
I have been running Longbow 2 to good success on 86Box (a pc emulator branched from PCEM). It's a win98SE environment with a voodoo3 card and the game performs as it was designed to at the time.

What has been interesting is the that the rockets still fall 20-50m short regardless of what targeting method is used (FCR/TADS). I remember a comment someone made elsewhere asking if the rockets had ever been accurate - even when the game first came out.

My theory is the maths is out and this is exacerbated by the frame rate etc. But it is still present on an emulates P233.


Moderated by  RacerGT 

Quick Search
Recent Articles
Support SimHQ

If you shop on Amazon use this Amazon link to support SimHQ
.
Social


Recent Topics
Carnival Cruise Ship Fire....... Again
by F4UDash4. 03/26/24 05:58 PM
Baltimore Bridge Collapse
by F4UDash4. 03/26/24 05:51 PM
The Oldest WWII Veterans
by F4UDash4. 03/24/24 09:21 PM
They got fired after this.
by Wigean. 03/20/24 08:19 PM
Grown ups joke time
by NoFlyBoy. 03/18/24 10:34 PM
Anyone Heard from Nimits?
by F4UDash4. 03/18/24 10:01 PM
RIP Gemini/Apollo astronaut Tom Stafford
by semmern. 03/18/24 02:14 PM
10 years after 3/8/2014
by NoFlyBoy. 03/17/24 10:25 AM
Copyright 1997-2016, SimHQ Inc. All Rights Reserved.

Powered by UBB.threads™ PHP Forum Software 7.6.0