Real Navigation Mod coming soon...

[vanjast]

Originally Posted by keltos01

are the stars accurate enough.?
k

So far with SH3 and SH4, it would seem so.

I must just play with the the sunrise/set moonrise/set times and game clock.

I have a problem getting rid the the mouse CTL-LClick, which looks to be 'hard-coded', but this is not the end of the world.

Must ask you guys a question:
What do you think of getting rid of the navigation bar completely for this mod - This would essentially disable anything the 'computer navigator' can do ?

[Schultzy]

What do you think of getting rid of the navigation bar completely for this mod

No half measures eh?
I think that once I get this mod up and running, I'll probably not touch the nav bar, aside from the weather report button. However, I suppose that button could be shifted somewhere else anyway, so why not.

One vote for the yes column

[tater]

Make sure the moon and sun are actually ~1/2 a degree across.

[Sledgehammer427]

hmmm. i have an idea

maybe make lighthouses selectable as targets...then you can get range/position fixes from them....bouys, channel markers too maybe?

EDIT: about making the nav bar disappear...maybe have a "chicken out" option where it slides out?
then you can save/reload to reset?

[DeepIron]

I must just play with the the sunrise/set moonrise/set times and game clock.

If you can fix this, I will be, frankly, amazed. I'm very curious how you're going to do a "look up" for the values needed to accurately predict these times based on what data? I don't think there is a ephemeral table in SH4... It could be done by rote calculation but the game clock is certainly *weird* in SH4 so those calculations would have to be tweaked...

Normally you'd need at least on longitude fix to get the correct time and hour offset to correct for UT. A latitude fix will determine the moon and sun azimuth.

Don't get me wrong, I hope you have great success. I've always hated being off the coast of Japan and still in darkness at 11:30 AM, etc...

Cheers.

[vanjast]

Originally Posted by DeepIron

.. but the game clock is certainly *weird* in SH4 so those calculations would have to be tweaked...

After the SH3 nav mod, I did a lot more reading with regard to ship clocks, It seems that the game clock is correct. The ship navigator has to adjust the clock according to longitude, just as it's done in the game.. this was a wierdo one for me too.
I'll look more into this and how to simpify it.

[Satch]

[quote=DeepIron]

I've always hated being off the coast of Japan and still in darkness at 11:30 AM, etc...
Cheers.

I assumed the game clock was on Pearl Harbor time or GMT. Anyone have thoughts on this? The QM had a GMT clock and he set all the division clocks to local time.

[starbird]

Originally Posted by Sledgehammer427

hmmm. i have an idea

maybe make lighthouses selectable as targets...then you can get range/position fixes from them....bouys, channel markers too maybe?

All you need are 2 fixes to find your position, no real need to have a lock for range. I guess if you knew the height of a lighthouse you could find a range tho. If the ingame maps are good enough, you could also use mountain peaks and other land features to plot your current position.

[Sledgehammer427]

my thoughts exactly

[vanjast]

Here's the Sextant inserted into the Obs-Scope.
I stopped at a British base, and asked them to modify the optics to something more suitable. The result is as follows.

The 1 degree divisions are now 16 pixels (instead of 17 ). This results in a slightly wider FOV ~ 2 degrees (I'm Skipper here and what I say goes - No arguments to the contrary.. ). The FOV is scaled to compensate for this.

Doing this enables the vertical (sextant) scale to be manhandled more easily.


Preliminary Users guide :-
- Place Horizon reference on sea horizon and measure angle.
- For angles above 60, swing scope vertical to 90 and read in reverse (One has a 0.5 Degree compensation here - Nothing I can do... it's a game visual problem)
- Sextant is red, so you can see it at night.




One of the gazillion tests...
Don't forget that Polaris is 0.5 degrees from North, Along the line from Cassiopeia



That's the scope done... Now down to the Almanacs...
Later..

[vanjast]

Originally Posted by tater

Make sure the moon and sun are actually ~1/2 a degree across.

You'll probably notice the Celestial Adjustments - 'Size' section in the proggy

[Munchausen]

That's gotta be the coolest celestial computation program I've ever seen.

[Rockin Robbins]

Originally Posted by tater

Make sure the moon and sun are actually ~1/2 a degree across.

Find a way to put the moon in the correct position at the correct phase at all times. It's hardwired, so the deal is already broken.

[vanjast]

I can change the game sun size, but the glare surrounding the sun is a problem at the moment. The moon and sun are just pictures, that can be changed AFAIK - looking into this.
As far as putting the moon in the correct position, I'm not sure of this at the moment, but you never know.

More later

[skookum]

Just did a quick test using the periscope to roughly measure the sun's altitude and azimuth. Checked them against a perpetual almanac and was surprised to find that the numbers were in the ball park (within 5 degrees) of my very (VERY) rough measurements. Of course for this kind of mod to work, we would need to be able to measure celestial body altitudes to the minute, rather than degree. And we would somehow need to confirm the accuracy of the in game celestial sphere against marine almanacs (or generate an almanac specifically for the SH4 celestial sphere).
Celestial navigation is pretty neat. Here's a link to a good site on the subject.

http://www.celestialnavigation.net/