Real Navigation with SH3

[don1reed]

Don't know if this has been tried with SH3 with any success, but Real Navigation with SH4 does work and I've got it to work with SH3 also> See Here: Beginning with Post #124 http://www.subsim.com/radioroom/showthread.php?t=116170&page=7

cheers,

[Gairith]

Was a do it yourself mod out there http://www.subsim.com/radioroom/showthread.php?t=113975&highlight=Real+Navigation
I used the sextant for a short time to try it out. Never went anywhere with it.

Nevermind, see you were already there awhile back. :oops:

[don1reed]

Same here, Gairith. This uses a "Python" script and "Stellarium", (both freeware) standalone pgms. While SH4 or SH3 is still running, I do a save, go to the script to input data of date/time UTC & Wx conditions then go to stellarium to get data from heavenly bodies, return to the game and at my leisure perform sight reductions and plot my position real time.

It works as in RL and performs like real navigation. Of course, if it's cloudy or foul wx I act accordingly.

cheers,

[dertien]

Hello Don,

Could you elaborate a little bit more on how you handle realnav in SH3 , what tools you use etc...

I have been looking all over the forums here, and all the information I found got me there halfway, or not at all.

Could you point us SH3 players to a link, tutorial, how to use this in SH3 ?

[don1reed]

Hey, dertien:up:

The point man on this is, 6SJ7GT, but he hangs out on the SH4 Mods forum and doesn't play SH3, or have it....However....I do :yep:

He's created a script using "Python" which interacts with both "Stellarium" and "SH4". I've changed the script to suit my computer's filing structure ( c:\documents and settings\...etc.) so that I now got it to work with both SH4 & SH3.

I say again: Python and Stellarium are FREEWARE.

Here's what it does:

1) While your sim of choice is running (SH3 or 4) do a save of the game but continue to run it.

2) Slip out of the sim leaving it running and run the Python script and input the Date/Time (UTC) and Wind speed & boat speed--exit Python.

3) Enter "Stellarium". Python will have automatically set up Stellarium to where it displays what the real world would look like at the geo coords and date/time that you are experiencing in the game.

4) The clock continues to run in Stellarium; however, you can simulate taking sextant sights (sun/moon/planets/stars) (click on body) as it gives Hs and Az of the heavenly bodies, by pausing Stellarium after each sight.

5) 6SJ7GT has also provided ephemeral data for the war years which will allow you to do a sight reduction for your acquired data.

6) Plot your course on a real paper plotting sheet or plot it on the F5 screen.

This procedure is not meant for the casual player as it is real navigation and is as time consuming as the real thing because it is the real thing.

Beginners should try this if they keep the waypoint tool and the sub/uboat icon on. The more experience and confidence you get with it, one can stop using the icon & waypoint tools.

In order to make it work from the get go I begin my patrols with waypoints to the mouth of the harbor to give Python a point of reference. It goes into the SH3/SH4 file in Documents and looks at the locations of the saved game and converts them into Lat/Long for it's use.

Best place to start is here: http://www.subsim.com/radioroom/showthread.php?t=116170&page=7

Begin with Post 124

I hope this helped.

all the best,

[don1reed]

There's been a lot of effort into making a realnav mod for SH3 with somewhat disappointing results. The combination of pgms SH3, Python & Stellarium is the most realistic to date. For one thing it will give the neophyte navigator a lesson of what it takes to move vessels around on the surface of the earth.(and below)

It will definitely take the player to a higher state of immersion. From taking sights to sight reduction, with or without weather's influence, a whole new game.

http://img176.imageshack.us/img176/9436/4cnsy9.th.jpg (http://img176.imageshack.us/my.php?image=4cnsy9.jpg)

[dertien]

Thank you Don1,

This looks like a thorough tutorial, have saved all pages, and will get studying immediately.

greetings

Dertien

[don1reed]

Roger dodger, dertien :)

If you need any help setting up your script for SH3 give me a shout.

There is a location in Stellarium that must be changed to read "utc". Let me know when you reach that place in your new adventure.

also, make sure you begin a new career with this just for the sole purpose of ironing out any bugs.

as always, cheers.

[Wartzay]

That SH4 real nav thread is interesting. I have been using the SH3 real nav mod that's posted around here somewhere, but lacking knowledge on how to shoot stars/sun I have been relying entirely on dead reckoning! :huh: However I have successfully completed 2 patrols on dead reckoning alone so it isn't impossible.

I bookmarked the pages that looked promising.

[ichso]

So you're still into the real nav thing don1reed ? ;)

I havn't played SH3 for a while now. I wanted to try your suggestion, but the site stellarium.org doesn't work.

Another thing: what about the stock SH3 bug that the the ranges aren't displayed correctly on the navmap ? When you travel west, lets say to longitude of 50°W then this should be a shorter way if you are further north than (for example) directly at the equator.

Doesn't this bug disturb your calculations or do you just take them into account ?

[don1reed]

Howdy, Ischo :)

Yep, still hangin' in there.

I have no probs with SH4. Crossed several time zones and results were rock solid.

In the middle of an SH3 patrol now, heading SWxW out of Lorient for BE86 in a typ9. I'll test that anomaly out shortly. Is there any particular Latitude were that shows up in game, or is it a fact all along the meridian 50W?

I really don't believe that it will present a problem as no matter where your boat is in the game, "Phython" looks at the geo coords of where it really is via the SH3 file in the documents section of the computer's files. The player usually has no knowledge of where his boat is in terms of geo coords as the player only sees KM grids. The game, however, is dealing with geo coords.

The name I've saved for my first patrol using this setup is "100". When I follow the directory path in my computer via the "SH3" doorway, the file name "100.map" is the one that Python uses to setup Stellarium to display what the uboat/sub sees on the F4 screen.

I'll let you know what happens.

PS stellarium.org is working now.

Cheers,

[jmr]

Don, I have several of your threads bookmarked that I use for reference as they contain pearls of information of translating real world mechanics into the virtual world of Silent Hunter. Good stuff.

So with this mod, how do you get around plotting way points without the origin of the waypoint line giving away your location? If the waypoint tool isn't used, how do you get your helmsman to hold his heading without drifting?

[ichso]

Hm, the 50° where just an example. I can't find it where I read this. Was it a dream ?
I looked through the whole GWX manual, perhaps it was in one of the real navigation threads around here, I don't know.

But I *think* I read somewhere that the SH3 map is flattened out, so that it doesn't take into account that travelling farther north (or south respectively) requires less time to cross the longitude markings.

So with this mod, how do you get around plotting way points without the origin of the waypoint line giving away your location? If the waypoint tool isn't used, how do you get your helmsman to hold his heading without drifting?
That was another thing that was bugging me some month ago when I last used real navigation.

[don1reed]

Aha, the trick, JMR, is I plot my last waypoint at the mouth of the harbor. It gives Python a reference point; all the saves of the game thereafter, supply's Python with the geographic codes (numbers that are divisible by 120,000)(don't ask me why it just does) wherever your boat is located. Its up to you the player to zero in with correct sight reductions to plot your location.

I'll show you a plot I'm doing in my present SH3 patrol as soon as I get it copied to imageshack.
edit:

Ok, here's a 3 star fix just outside of Lorient with attendant sight reductions.

http://img379.imageshack.us/img379/4472/100lorientgw8.th.jpg (http://img379.imageshack.us/my.php?image=100lorientgw8.jpg)

cheers,

[don1reed]

oops, sorry Ischo, I apparently simul posted when you did and didn't see what you wrote.

Ok. Got it. I believe I know what you're talking about now. Yeah, this method isn't effected by that. Mercatur projection. I know it won't work if you try to sail a great circle course.

Here at least Python uses the numbers that the game produces and I'm always in the ball park. I've never been exactly spot on but that ok, I never been totally off the chart either.

So far with this method, by making typhoon quality wind >100 knots, the furthest off I've been is 43nm with the tests I've made using SH4.

This is navigation as I know it to really be. (less foul wx, of course)

You can always press CNTL Left mouse button to see where you really are if you're truely lost. :)

Let me add a VERY important point.

Just prior to going to Python to enter your data, you must do a SAVE. This save is what tells Python where your boat is last located for real.

So, every celestial sight you make you must also do a save-game and you must keep the name exactly the same each time. this writes-over preexisting saves as you know, but also eliminates some forms of cheating or do-overs, if you will.

Hope this helped.

[ichso]

Thanks, I will try the whole thing again on my next patrol.
The celestial navigation has always been very emersive for me.

I think, if you just do those position markings often enough, the problem I mentioned shouldn't be present such much as that one would recognise it. I will come up with experiences and results as I test it more extensively.

So, happy navigating :arrgh!:

Nice drawings, btw.
I will stick to painting on the nav map first and use paper later, when I accidentely ereased all my ingame drawings :D

[Pisces]

I didn't have trouble going to the Stellarium site either this evening. Anyway, the right link to the site is:

http://www.stellarium.org/

[don1reed]

Here's a copy of how I've got my version of Python setup to work with SH3. If anyone's interested, you'll have to change the directory to suit your system.

You'll note after ...\\career\\...I've inserted my name, but this is where you'll insert your skipper's name.

Also, after... \\0\\...I've (file://\\0\\...I've) inserted my save-gave name = "100" plus add the file extension *.map. Whatever you call your saved game, this is where to put it in the Python script.

You'll have to use the same name for each patrol or change this script to reflect whatever new name you decide to use.

Oh, and btw, I've named my script: SH3random.py and made a shortcut out of it for the desktop so I can easily click on to it while SH3 is running.

You can copy mine, make the necessary changes using Notepad or similar writing tool and whatever you name it don't forget to place the extension *.py at the end. Once you get your copy of Python you'll see where to place this script.

Cheers,



#Python 2.5.2 (r252:60911, Feb 21 2008, 13:11:45) [MSC v.1310 32 bit (Intel)] on win32
#Type "copyright", "credits" or "license()" for more information.
#************************************************* ***************
#Personal firewall software may warn about the connection IDLE
#makes to its subprocess using this computer's internal loopback
#interface. This connection is not visible on any external
#interface and no data is sent to or received from the Internet.
#************************************************* ***************

#IDLE 1.2.2
#>>> #By Michael Jones, 01/01/2008.
#This program reads the latitude and longitude data for a
#sub in Silent Hunter IV and creates a startup script for
#Stellarium. This sets the Date, Time and Location of the
#sub in Stellarium, allowing players to use celestial navigation in the game.
#
#Modified by Castorp345 to include randomization, 03/24/2008.
import string
import random
random.seed()
#read savegame. Change the directory on the next line to point to SaveData.map in your saved game directory.
#NB you must have plotted waypoints in-game for this to work!
f=open("C:\\Documents and Settings\\Donald Reed\\My Documents\\SH3\\data\\cfg\\careers\\Don Reed\\0\\100.map",'r')
content= f.read()
f.close()
#find lat & Lon in the file
start = content.find("Waypoint")
longst = content.find("Pt0=",start)
longnd = content.find(",",longst)
latnd = content.find(",",longnd+1)
#convert to dec deg
longitude = float(content[longst+4:longnd])/120000
latitude = float(content[longnd+1:latnd])/120000
#get date, time, wind speed, & boat speed (input)
date = raw_input('yyyy/mm/dd :')
time = raw_input('hh:mm :')
wind = float(raw_input('wind :'))
speed = float(raw_input('speed :'))
#perform randomization operations on location coordinates
wind1 = random.uniform(0,((wind + 1) * .0083125))
wind2 = random.uniform(0,((wind + 1) * .0083125))
speed1 = random.uniform(0,((speed + 1) * .0083125))
speed2 = random.uniform(0,((speed + 1) * .0083125))
longitude = longitude + wind1 - wind2 + speed1 - speed2
latitude = latitude + wind1 - wind2 + speed1 - speed2
#Write startup script. Change the next line to suit for your Stellarium startup script.
stella=open("C:\\Program Files\\Stellarium\\scripts\\startup.sts",'w')
stella.write("date utc "+date+"T"+time+":00\n")
stella.write("moveto lon "+str(longitude)+"\n")
stella.write("moveto lat "+str(latitude)+"\n")
stella.write("script action end\n")
stella.close()
#now open stellarium and take your star sights

[jmr]

Seems like aaronblood's Mobo would be the perfect tool to supplant the traditional ruler/paper method for celestial navigation. Just grab a snapshot of the SH nav map, paste it into Mobo, set the scale accordingly and you're good to go.

At least I think it would work OK.

[6SJ7GT]

Don & all,
I don't have SH3, but hear my method works in SH3 also.

Here is a tutorial on a simplified method of celnav for the game. Thanks to Don for his help on this.

SH4 simplified celnav tutorial (http://users.ameritech.net/mjones004/SH4_Celnav_Tutorial.pdf)

Mike

[don1reed]

lol, I must have just missed you on the SH4 forum, Mike.

Excellent job :up:

[jmr]

So when you have your position, how do you mark your location on the SH3 navmap if it doesn't have Lon/Lat markers?

[Pisces]

So when you have your position, how do you mark your location on the SH3 navmap if it doesn't have Lon/Lat markers?It does. Look at the edge of the map-view carefuly, and pan the view.

[jmr]

I'm going nuts here. I'm running GWX 2.0 and I'm not seeing Lon/Lat numbers on my chart in the F5 view.

[don1reed]

JMR
all around the perimeter of the F5 screen are alternating black/white, hacture marks. they represent the degrees. What most of us have been doing in counting (left or right) from prime-meridian, or at the beginning of a patrol, the Lat/Long of the port is given and we count from there.

Most times, when nav is primary, I draw in vertical & horizontal lines connecting those hacture marks, top with the bottom, and left with the right to give me a geo coord chart.

[dertien]

Hi, does anyone know how do you convert the positions from the campaign_LND.mis to real lat/lon values ?

for ex

[Unit 60]
Name=Heligoland
Class=NavalBase
Type=407
Origin=German
Side=2
Commander=0
CargoExt=-1
CargoInt=-1
CfgDate=19380101
DeleteOnLastWaypoint=true
DockedShip=false
GameEntryDate=19380101
GameEntryTime=0
GameExitDate=19450503
GameExitTime=2359
EvolveFromEntryDate=false
Long=946687.000000 <<<<<<<<<<<<<
Lat=6500844.000000 <<<<<<<<<<<<<
Height=-27.334999
Heading=180.000000
Speed=0.000000
CrewRating=2
DelayMin=0
ReportPosMin=-1
ReportPosProbability=100
RandStartRadius=0.000000
NextWP=0


thank you

[don1reed]

I believe you divide those numbers by: 120,000

I came up with 54 deg 10.4 min N by 007 deg 53.3 min E.

btw: any negatives (-) numbers LAT = South, LONG = West

[Gairith]

I don't know if this will have any bearing, but check this thread post 1 and 4

http://www.subsim.com/radioroom/showthread.php?t=134939

[Pisces]

I believe you divide those numbers by: 120,000

I came up with 54 deg 10.4 min N by 007 deg 53.3 min E.

btw: any negatives (-) numbers LAT = South, LONG = WestThat looks about right in my atlas. :)

[don1reed]

This is how I determine Geo Coord in SH3.

If you'll notice the F5 screen, I've taken the "ruler" tool and connected the hacture marks at the top of the chart with those at the bottom (Meridians); and likewise, I've connected the hacture marks on the left(west) side of the chart with those on the right.

These hacture marks, the alternating white/black marks around the perimeter of the chart, are the Latitude & Longitude degrees. They only show up when you're within a certain range. If you zoom in/out too far, they will disappear from the chart.

You will also note, that I've used the ruler tool to draw in the Longitudes from my homeport, Lorient, using Roman Numerals. That way it's easy for me to keep track without having to go all the way back to the prime meridian to recount.

Too time consuming, you say? Well, think about it for a second, what was everyone doing in RL to prepare for a voyage? The grunts were restocking with ammo, victuals, fuel...
...the Navigator was futsing with charts, publication, notams, mine-field locations, wx reports.

I personally take the time to draw my course using the ruler tool from the mouth of the harbor.

I no longer need worry about the helmsman falling asleep at the wheel and drifting all over creation. 6SJ7GT's Python script with Stellarium now lets me navigate and rely on the heavens above to show me the way. I pretty much do most of my navigation on plotting sheets off screen, and so far, comparing them to the F5 screen, they are identical.

It takes 10 hours between evening twilight round of stars FIX to dawn twilight round of stars FIX, and unless you're sitting at the cpu with your eyes plasterd on the screen you'll miss the suttle drift (or in storm, major drift). I convert km into nm and use D=SxT to determine my DR and assumed position and plot my sight reductions from there...and viola, the heavens have placed where I really am, not where I thought I was using DR alone.

I've noticed, along with everyone else, that the game retards DR by about 40 nm or so...still, with Python and Stellarium, I no longer worry about it.

Cheers,



http://img291.imageshack.us/img291/1489/1sh3cm8.th.jpg (http://img291.imageshack.us/my.php?image=1sh3cm8.jpg)

[ichso]

*Thumbs up*
Some very good suggestions don1reed that I'm gonna try out as I get time to play again. :up:

[Uber Gruber]

I like it! Will give it a go when current patrol finished :up:

[jmr]

Little off topic, but in the real world, how do you use a sextant on the deck of a heaving ship?

[ichso]

One question:
How do you guys make SH hide your sub icon on the nav map ?

I have some edited files 'UnitSub*.tga' in 'data\menu\gui\units\'.
But when in the game, I still see a flickering little dot on the map (instead of the sub icon). This is really annoying because I always have to look away from that to not >>accidently<< cheat by seeing my acutal position when I shouldn't. :-?

Little off topic, but in the real world, how do you use a sextant on the deck of a heaving ship?
That I have asked myself too from time to time. Perhaps it takes just a bit longer to get a reading you are satisfied with ? Would make it harder to navigate, that's true.

[don1reed]

@jmr: The construction of a sextant allows the navigator to view the horizon through the horizon glass. The heavenly body is viewed and reflected by a mirror at the top of the index arm to be co-viewed through the horizon glass, and by slowly turning the micrometer drum at the bottom of the index arm, brings the horizon and body together as one.

The stars appears as pinpoints whereas the sun, moon and planets need corrections for semi-diameter and oblateness and horizontal parallax(moon) due to their relative larger size.

While the deck is pitching, the navigator tries to remain plumb & level, keeping the heavenly body and horizon in near proximity in the glass. He waits until his craft is atop a wave (not in a trough) to make his final adjustment to bring the horizon the body together as one and yells (if very windy) "MARK!). His time-keeper jots down the watch time while the navigator reads his arc and gives the angle to the time-keeper and goes and makes either a round of star sights or 3 or more sights of the sun/moon to get an average. Its a balancing act to be sure, but becomes second nature to those who do it for a living.

@ichso: It's been awhile since I eliminated my icon and I don't exactly remember where I got the mod; but the mod for SH4 may work for SH3 also...it's worth a try.

Look for the mod "no_sub_on_map" by Thendash.

cheers,

[6SJ7GT]

To all,

I put everything needed for celestial nav in an archive here. It's not a game mod so much as a hybrid. I take the sub position from a savegame and put it into a planetarium program. Don was one of the people that adopted this and helped me put it together. He says it works on SH3 also, so the savegame files must be similar to sh4.

there is a tutorial here (http://files.filefront.com/Short+Tutorial+on+SH4+Celnpdf/;10021777;/fileinfo.html) if you want to try celnav.

For anyone that wants to try this, let me know if there are any problems.
Celestial Navigation in Silent Hunter (http://files.filefront.com/Celestial+Navigation+for+H47z/;10021798;/fileinfo.html)

Fair skies and smooth sailing,
Mike

[don1reed]

Great work, Mike! :yep:


-...-

ichso: you'll have to convert from *.DDS to *.TGA for the no_sub_on_map to work, however.

btw: it's the same three files that Vanjast changed in his original RealNav mod.

[ichso]

Then it's probably some weird graphic effect.

I recently built me a new computer and I am now using a Nvidia card. Before it had been an ATI card. I also experience some glitches in the external sceneries. So it may be because of the graphics drivers or something.

Currently I'm using Vanjast's tgas from his RealNav mod for SH3 to hide my boat on the nav map.

[don1reed]

you might try removing then reinstalling. IIRC all I used from his mod was just those three tga's in the UNITS directory.

[ichso]

I also use just those 3 files. I checked them and there are just transparent tga-files.

I think it's on most or even all the zoom levels, didn't check it on purpose yet.
Or it has something to do with the higher resolution patch ? That's the only thing that I'm using now and that I wasn't already using before.

[ichso]

That might be a good hint.

Before I used to use the RNM as it was but as I started playing again I cut it down to make the U-Boat invisible and I'm still having the plotting tool available.

[don1reed]

Ok, 1st patrol starting with GWX2.1, OLC Ubermod, & No_Sub_on_map. Using Python & Stellarius for navigation.
DTD 1.8.1939 out of Wilhelmshaven for BE17.

Drew in course to follow with surrounding Lat/Long. Zoomed out to show the overall effect.

http://i77.photobucket.com/albums/j42/donhreed/GWX21.jpg

[AndyW]

Sorry for bumping this thread, but I wonder if there was ever a solution for this tiny flickering wake pixel giving away your boat's position on the Nav map.

Actually I'm using Vanjast's Real Navigation mod and replaced all TGA's coming with it, but this remaining pulsing dot is a real spoiler.

Any hints, anyone?

Thanks,
AndyW

[Yoriyn]

Can anyone help me to force stellarium to run startup script?
I wish to start my celestial navigation, follow step by step the running process, but it don't work for me. Payton script work fine saving my position data to file startup.sts. And this is a place where my problem start. If I run stellarium it show me a default location somewhere in Zambia and actual date/time. I can't run startup script. The file startup.ssc is almost empty that's all what's in file:

//
// Name: Startup Script
// Description: Script which runs automatically at startup
//

Please help Me :wah:Whats wrong?

[don1reed]

Howdy, yoriyn. I've got to take care of some personal chores here; but, will get back to you later today. Due to our time differences, it might be early tomorrow.

In the meantime, perhaps one of the old hands on this thread will take up the slack.

Cheers,