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vanjast
02-16-11, 02:54 PM
I haven't seen this yet - but you can scream at me if it has be done.

Here's a working sextant in the Obs Scope - accuracy to about 1/5 degree (I guess).

http://www.vanjast.com/NavMod/Sextant.jpg

It's essentially the same idea as the previous SH3/4 sextant, and used the same way.
Porthole: = 768 pixel diameter (24 pixels per degree at 32 degree FOV) - easy to work with
Zoom levels: = 3 levels (Sextant [lowest], 2 other levels [currently 32 and 8 deg FOV])

Interesting notes:
The sky view 'lens', that is the optical view of the stars is a fish-eye lens in the vertical plane, with stretching as you move away from the centre of the scope view.

This apparently does not effect the bearing indicator and scope rotation in the horizontal plane. Maybe the game compensates for this already. It seems that the sky FOV is seperated from the sealevel stuff.

Wot I did
=======

- I tried to get rid of the fisheye effect by a combination of AngularDistance, portviews, ClipDistance and Zoomlevel - nothing worked.

- I eventually settled on the games default AngularDistance, etc.. so as to be compatible with the big mods, hopefully

- Locking the min scope angle = 30 degrees, the then adjusted the zoom level so that the horizon was on the lowest line (0 Degrees). This meant that the 60 Degrees line would be in the right place.

- With 12 test missions at 5 degree latitude increments I adjusted the indicators until within position - taking into consideration the 0.5 degree offset of Polaris from True North, which was at an angle from Casseopeia.
Longitude line is Greenwich.

Other notes:

- I'm doing this on my laptop with a 1280x800 res, but after fiddling as bit I found that the best obscope and periscope masks, to get that nice round hole was 1240x768 image size. If I'm not mistaken the game locks at 768 vertical, but fudges it up according to your screens horizontal res.
IOW those ingame graphics settings and ratios of 4:3, 5:3, 8:5 mean zippo, unless you have a screen of exact proportions.

- I made my 'porthole' = 768 vertical pixels, and then adjusted the width of the mask until my pic was round - I measured with a ruler :) - This means that my screenshots are compressed, but an image editor sorts that out.


The image is without any frills, so what I can do is upload this basic scope view, plus test missions, and you can, adjust(add to) it to your screenres, as there is no-ways that 'one will fit all'.

:)

Sailor Steve
02-16-11, 03:16 PM
I don't remember if it's been done for the 'scope or not.

But it's pretty dang cool! :sunny:

Hylander_1314
02-16-11, 03:53 PM
Now that is a novel idea! I hope it is made to be compatable with the supermods, RFB, TMO, and FOTRS. What a great addition it will make!

vanjast
02-16-11, 04:05 PM
Now that is a novel idea! I hope it is made to be compatable with the supermods, RFB, TMO, and FOTRS. What a great addition it will make!
It should be easy to implement as it only requires Obs scope adjustments, which is usually seperated from mainstream modding, except for the cameras.dat file, and an Obs scope skin.
:)

Hylander_1314
02-16-11, 10:08 PM
Hopefully, it won't be too tedious to do. Looking forward to this one for sure! :up:

keltos01
02-17-11, 07:30 AM
does that mean the stars are in their correct positions then ? and their rotation is also correct ?

very nice tool !

congrats !

keltos

vanjast
02-17-11, 01:07 PM
does that mean the stars are in their correct positions then ? and their rotation is also correct ?

I haven't checked on this but Polaris (North Star) is at the correct lattitude positions.

I think the sky system is unchanged from SH3, but I'll check on this as I have many books on astonomy and a Planisphere to play with. From what I remember from the last time I looked into this, all seemed OK. It was just the time of day clock references that were a problem - but I have a feeling I was barking up the wrong tree with this.

:)

fitzcarraldo
02-17-11, 07:35 PM
I haven't checked on this but Polaris (North Star) is at the correct lattitude positions.

I think the sky system is unchanged from SH3, but I'll check on this as I have many books on astonomy and a Planisphere to play with. From what I remember from the last time I looked into this, all seemed OK. It was just the time of day clock references that were a problem - but I have a feeling I was barking up the wrong tree with this.

:)

For SH3 the Real Navigation works with an external program (stellarium), because the skies arenīt accurate for determining position. But the skies of SH4, I donīt know (It seems the same problem...).

Many thanks!

Fitzcarraldo :salute:

TorpX
02-18-11, 12:49 AM
Has anyone here researched the Celestial Navigation thread?
Much of this was discussed at length there.

vanjast
02-18-11, 05:57 AM
For SH3 the Real Navigation works with an external program (stellarium), because the skies arenīt accurate for determining position.
That doesn't sound right... If the SH3 sky's are not accurate then then no external proggy will work anyway, as your reference is the game sky.

I did a test run in SH3 and got an accuracy within 5Nm on first attempt. Somebody else actually got an accuracy down to 100m by triangulation.
I think the idea is to check where the game sky (almanac) places you, and then make adjustments to fit this, and then there will be a game accuracy which is more important than an external program accuracy - even though the methods are the same.

:)

fitzcarraldo
02-18-11, 06:33 AM
That doesn't sound right... If the SH3 sky's are not accurate then then no external proggy will work anyway, as your reference is the game sky.

I did a test run in SH3 and got an accuracy within 5Nm on first attempt. Somebody else actually got an accuracy down to 100m by triangulation.
I think the idea is to check where the game sky (almanac) places you, and then make adjustments to fit this, and then there will be a game accuracy which is more important than an external program accuracy - even though the methods are the same.

:)

Thanks for the information; really I didnīt test real navigation, only I read the threads about that (firtstly, the Cellestian Navigation Thread). The "Stellarium" application is an external program, I suppose it is for compare information of the skies in SH3/SH4.

Best regards.

Fitzcarraldo :salute:

vanjast
02-18-11, 07:01 AM
Has anyone here researched the Celestial Navigation thread?
Much of this was discussed at length there.

Yeah! we know and although in real life navigation there are many more things to consider, in game there are much fewer items to worry about to get a fix.
Time, Longitude and Latitude - no need to worry about light refraction, atmospheric conditions, ect.. as it seems these are not modelled.

Anyway, this is about having a sextant in the scope where the only adjustments needed are the scope skin and one extra zoom level in the scope optic parameters.

:)