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Old 12-15-18, 05:25 PM   #1
Greystone
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Default The old time enigma

From what I gather, a lot of you have run into out-of-whack temporal disturbances, as I have, like the sun rising at 1am, setting at noon, etc.
I did a search here and ran across some discussions on the topic and, being a bit of a simpleton, my eyes glazed over just scanning the various discussions on the subject.
I really have no desire to even attempt to jump through tedious mental & cognitive hoops (for me) to try and ascertain what the actual local time is when playing the game.
What would solve the problem though, for me, is knowing what time of day it is for the AI.
If the sun is high in the sky, but the clock says 2am, does the AI see it as daylight also, or do they see the world as it'd look at 2am?
Or, if it's black as pitch out, can I count on the AI having a hard time seeing me even though the time is shown as 3pm?
As usual, thanks for any help..
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Old 01-18-19, 09:05 PM   #2
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Default SH4 is as astronomically accurate as you could ask for.

Quote:
Originally Posted by Greystone View Post
From what I gather, a lot of you have run into out-of-whack temporal disturbances, as I have, like the sun rising at 1am, setting at noon, etc...
Mod-related bugs aside, I can assure you that there is nothing wrong. I, too, have read many posts and threads related to the sun rising and setting at 1 am, and the difficulties involved with celestial navigation in the game. Some of these are written by people who know what they're talking about, but most are not.

I proved everything was fine (at least to myself) because I was able to navigate by the stars from Pearl Harbor to Midway over the course of a three-day voyage (and later, all the way to Japan) without any mods or outside software other than an Excel spreadsheet which I wrote to do the tedious mathematical calculations for me. It was so accurate that I found Midway right off my bow on the first attempt. I couldn't have done that if there had been anything wrong.

One thing I've noticed is that most of the discussion centers around sunrise and sunset times. There are a lot of reasons why people have difficulty with this, and they chase their tails trying to figure it out. There's a lot of effort that goes into calculating "real local time" for the sub's present "time zone" when time zones have nothing to do with what time the sun rises. Instead, there is Sun Time. Every point on the surface of the earth has its own unique schedule when it comes to Sun Time, it is, therefore, quite meaningless and useless for our purposes. Tracking the sun is an exercise in futility, as well. In the game, it's so big that it's difficult to tell exactly where it is. The same goes for the moon. I can tell you, however, that the sun and moon are not 180 degrees from where they need to be, nor 90 degrees, 50, 40, not even 10. Just accept it, SH4 is astronomically correct.

Pearl Harbor base time is UTC -11 hours. Perth base time is UTC +8. Setting a constant base time makes more sense than anything else. If you see something that doesn't make sense to you, first make an effort to understand why it may be RIGHT!

I could go on and on about the nonsensical things I've read in some of these posts and threads, but just for example, I'll use a recent one: "Base Time 2018" by FrontRunner, propbeanie, et al. They think they found a problem with sunset times caused by the accelerated frame rates of newer computers, and to try to prove it, they used a timing experiment with a moving platform (sailing north at 15kts). Because Sun Time is different on every different point on the surface of the earth, the moving platform tainted their results. It's worse because they chose a date close to the Winter Solstice, when sunrise and sunset times vary with latitude the most. After all that, their conclusion about frame rates isn't consistent with the effect they were looking at. If the game were designed for 24fps and accelerating that caused the "sky to turn" at the wrong rate, 30fps would cause a solar day to take 19 hours and 12 minutes in the game. They didn't find anything like that.

Your question about whether the AI can see you at night is a more complex but less important one. As a general rule, do not be on the surface when a ship is any closer than the point at which you can just barely see it. "If you can see them, they can see you." Real submarines in WWII used to track ships by the smoke above their stacks, and not even by visual contact with the ships, themselves. Night surface attacks were common, but so were sunken U-boats.
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Old 01-18-19, 09:40 PM   #3
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Really?... - I'll have to remember that one. "Don't be on the surface when a ship is any closer than the point at which you can just barely see it."... got it.

I'm glad you were able to find Midway, and Japan too, more power to you and your "real" navigation on a cylinder. We are NOT talking about that in the "Base Time 2018" thread. Read the thread
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Old 10-19-19, 10:09 AM   #4
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I didn't say you were talking about celestial navigation in "Base Time 2018," so maybe you're the one who needs to learn how to read.

Yes, the world is modeled as a cylinder in SH4. So what? The game still displays the sky as it appeared at the time, latitude, and longitude of your sub. This is why I can apply real-world navigation techniques to the game.

I guess you're still playing at beginner levels if you stay on the surface so much. If you want to crank it up to realistic, you're going to have to learn some new tactics. Would you like some more pointers?
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Old 10-20-19, 08:16 PM   #5
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OK, another attempt at 'spaining it Lucy... The game was written circa 2005 during the Windows XP days. As such, it uses DirectX v9.0c (which has a "timer"). The game uses multiple "timers" to run the game. The "timers" have to be co-ordinated, or synced with each other. A computer has no knowledge of plus (+) or minus (-) Meridian, degrees of latitude and longitude, or anything like that. It counts zeroes and ones. On and Off. The human "interprets" it. Front Runner, in the aforementioned thread found that running the game higher than 30fps resulted in a game that would go "out of sync" with itself after he played days of the game at 1x, or at real time. If he used mid-levels of TC and the 1x real time, the game did not "drift" out of sync with itself as much. In other words, his "base time" shifted the more he played at 1x real time. Once he restricted the game to 30 fps, there was no longer any "drift" in the clocks, hence a more accurate rendition of the night / day sky, making it possible to predict the moon cycles more accurately. This does not have anything to do with my ignorance of this, that, or the other. If you restrict the game to 30 fps, which is what it was written to, you will then end up with more accurate SH4-world time... Once again, I attempt to explain that the cylinder land and sea has a clock. The sun and moon seem to have a separate clock. 30 fps, tied to the video card, keeps them together.
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Old 12-15-18, 07:25 PM   #6
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Well, speaking from a metaphysical point of view: maybe...

That's what Front Runner was getting at in his thread "Base Time 2018". It has been discussed before in a few other threads, but I don't think anyone has gotten to the root of the problem yet, like Front Runner has. The game keeps really accurate track of the time of day (or night) - but only under certain circumstances.

The game engine is basically SH3, from 2005, so you can say it's probably 2003 software technology, if not older. The idea of using something truly "stable" to keep track of time of day was not well-programmed for future computing. With computers that are as fast and efficient as they are today, the games' (SH3, 4 & 5) get out of whack when running at "real" time. They can draw the screen at a much higher rate than the computers of 10 years ago could. Since the use of the higher Time Compression settings basically negates the effect of screen refresh rate, and hence "time of day" being tied to it, the effect is not seen.

Basically, what Front Runner describes is a cumulative effect, where after playing the game for some time, sunset and sunrise (and the moon phases) all get out of whack, and you might be seeing the game as representing night time, but the game AI is seeing it as daylight, such that it seems the enemy is either clairvoyant, or has a new top-secret radar that the US doesn't know about... So "yes Margaret, you can be attacked at what you think is night time, by an enemy AI that thinks it's day time." One way to alleviate the issue is to Save the game, exit, come back in, and load the Save - presto change-oh, everything is back in sync... What a "fix", eh? Like so many other of the games' fixes...

Using the nVidia Control Panel, if you have an nVidia card, or maybe the ATI / AMD CCC for one of their cards, and you might be able to set the game to not go beyond using 30fps (Frames Per Second) when it "draws" the game assets, such as ships or sea or land, etc. That seems to be the solution. Conversely, if you have an older computer, one that you can't get above 30fps anyway, no worries - that might actually be "cutting-edge technology" for the games.

Maybe we can talk Front Runner into doing a picture-laden tutorial on setting up the nVidia control panel for this...
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Old 12-15-18, 11:30 PM   #7
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propbeanie; Thank you!... Yes, I recall seeing Front Runner's posting on this, and remember admiring his insight and persistence to get to the bottom of the time issue, but couldn't really grasp anything beyond the admiration part, partly because I'm getting a bit long in the tooth and my senior moments are turning into background. Also, I just want to play the bloody game and not spend 80% of my time researching & tinkering to get it to run right. I sure picked the right game to do that, eh?
Thanks to your breakdown, I now have a basic understanding of what's going on. The reference to saving & reloading the save is a godsend. No, wait; scratch that.. I just started the game, loaded my last save, and the sun is where you'd expect it to be around 3 or 4 pm and the time shows 22:30. Saved that, exited, and reloaded and all's the same as before; no change. (throws hands in air)
I don't know, maybe I'll just assume the AI sees everything & dive whenever I detect any of 'em; pretend I'm playing Silent Prey 4.


Addendum: I just became aware of Front Runner's and propbeanie's newest posts on the subject, where I'll turn my gaze whenever I think I can handle more "research and tinkering".

Last edited by Greystone; 12-15-18 at 11:57 PM.
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Old 12-16-18, 08:38 AM   #8
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If you have an nVidia card, that Steam link in Front Runner's post applies, and is relatively easy to step through, even for us more "senior" er uh, wanderers... in spite of "background" and tinnitus...

Your Save didn't "correct" the time, eh?... What are you playing, Stock or any mods?... It would definitely be easier if the game had a "Zulu -10" or whatever designation, wouldn't it?
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Old 12-16-18, 03:41 PM   #9
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Hey propbeanie.. Yup, the save, go out, & reload the same save didn't give the expected result. I'm playing stock SH4 with the following mods:


BBC World (for the radio)
No Surface Hydrophone (an attempt to correct getting hydrophone readings while on the surface)
Less Water Limber Holes
Webster's Underwater Visibility for v1.5
" Better Waterline Colors for v1.5
" Better Sub Marker


I'm running it on Win7 with an nVidia GTX 750Ti
I have the Vertical Sync checkbox checked in Options
Have the game installed in C:\SH4


I did go to the Steam link in Front Runner's post and followed the instructions; you're right, it was a rather simple affair..


When I went back in, the situation was the same and that made sense, to me anyway; I mean, the save is the same save and I wouldn't expect that lowering the fps would alter the parameters within the save. I figure, if the prevailing theory is right, the time discrepancy will now stay the same as opposed to continually altering as it had before the change I just made with the nVidia Control Panel. I'm hoping that, at the end of my current mission, somewhere, somehow, through the transition from the end of the patrol, my time in port, and my departure into the following patrol, the game'll revert to displaying the correct time. One can only hope..


Tinnitus? You've got tinnitus? Ah, a kindred soul... I drove a cab in San Francisco for 35 years and about 30 years ago, some idiot driver in a Mercedes, blasted her horn about 4 feet from my ears and I've had a high-pitched sound in my ears 24-7 ever since. Lovely, ain't it?


Again, thanks for your generous help.

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Old 12-16-18, 04:45 PM   #10
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Being back at your home port, should definitely (in theory ) fix the discrepancy. When I was younger and working catch-as-catch-can in the late 70s early 80s, I had one noisy job after another ($2 an hour cash). In the late 80s, I did construction. Between chainsaws, jack-hammers, boom trucks and all sorts of what-not, all I hear now is the wife (hopefully) and a steady "hisssss". At least it's in stereo, and if I turn my CCR up loud enough, they still sound just as good as 1969 / 70...



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Old 12-17-18, 09:54 AM   #11
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Quote:
Originally Posted by Greystone View Post
Hey propbeanie.. Yup, the save, go out, & reload the same save didn't give the expected result. I'm playing stock SH4 with the following mods:


BBC World (for the radio)
No Surface Hydrophone (an attempt to correct getting hydrophone readings while on the surface)
Less Water Limber Holes
Webster's Underwater Visibility for v1.5
" Better Waterline Colors for v1.5
" Better Sub Marker


I'm running it on Win7 with an nVidia GTX 750Ti
I have the Vertical Sync checkbox checked in Options
Have the game installed in C:\SH4


I did go to the Steam link in Front Runner's post and followed the instructions; you're right, it was a rather simple affair..


When I went back in, the situation was the same and that made sense, to me anyway; I mean, the save is the same save and I wouldn't expect that lowering the fps would alter the parameters within the save. I figure, if the prevailing theory is right, the time discrepancy will now stay the same as opposed to continually altering as it had before the change I just made with the nVidia Control Panel. I'm hoping that, at the end of my current mission, somewhere, somehow, through the transition from the end of the patrol, my time in port, and my departure into the following patrol, the game'll revert to displaying the correct time. One can only hope..

Again, thanks for your generous help.

I haven’t tested that within a save game. Let us know the results of starting a new patrol when making the recommended Vertical Sync changes while in career. Theoretically, your next patrol should start the BT Clock anew.
Keep in mind that there will still be a Time Zone difference between your “Base” and your “Patrol Area”. For example Pearl Harbor Base Time would be different than the observed Base Time in Empire Waters. The old threads about Base Time cover this very well.
I kind of tripped over discovering this issue because up until recently I had almost always chose a Pearl Harbor career start and basically ignored the own ship Base Time Clock because the east west time zone changes fudged it up anyway. Well, I chose a Brisbane start and my assigned area was the Bismarck Sea, within the same Base Time Zone. After playing several days at 1x (Vertical Sync in game off and “balls out” frame rate 240 fps) to get there, I noticed that Sunset/Sunrise, Moonset/Moonrise were way off! Like hours off.
My sub is in darkest night, base time shows it should be daylight hours and I’m getting attacked by aircraft. Whoa! That’s when I put my thinking cap on and somewhere along the line of experimentation I discovered the link between Vertical Sync On/Off and the SS/SR,MS/MR error differential.
Currently I am on my 4th day underway with the recommended settings, (in game vertical sync off, nVidia control panel settings forced 1/2 refresh rate 30 FPS, and adaptive vertical sync on through the nVidia control panel.) My 4th day sunrise was 11 to 12 minutes late vs Almanac. I have noticed that the sunsets are tending to drift later. My 3rd day sunset was 20 minutes late while the following Moonset was only 11 minutes late. Very acceptable after almost 4 days at 1x play.
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