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Old 09-11-10, 05:35 AM   #16
Diopos
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Quote:
Originally Posted by Nisgeis View Post
The chart is flat, but the modelled 3D world you see is round, but the water is flat. Result is that ships 'sink' into the water at long range to model the horizon obscuring them, even though you can see the water horizon behind them.
As far as navigation is concerned the world is flat. The distance between meridiens is same in the equator as in any other latitude . The North/South Poles are not points but lines (the meridiens don't
"converge"). They use a Mercator type of projection not as a "map" of the world but as the world itself.

What exaclty do you mean by " ...but the modelled 3D world you see is round..."?

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Old 09-11-10, 07:48 AM   #17
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I did a little test myself lastnight. Heres what i did. Left port in S-39,
(at Java) sailed out the channel and plotted a course dew south for five knotical miles and let her go ahead standard. We pushed 9knots as i waited. The sea was very calm and a 5knot wind from 260. My rudder was at 4 degrees port. (I am using FOTRS btw)
that was to make strait south... now I turned round and went back and had 5* to starboard.
turned to 180 again manually and dive to PD and ran at 5 knots i noticed myself drift to a heading of 178 in 5 knotical miles.
Tell me theres no current.
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Old 09-11-10, 10:31 AM   #18
Diopos
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Originally Posted by rein1705 View Post
I did a little test myself lastnight. Heres what i did. Left port in S-39,
(at Java) sailed out the channel and plotted a course dew south for five knotical miles and let her go ahead standard. We pushed 9knots as i waited. The sea was very calm and a 5knot wind from 260. My rudder was at 4 degrees port. (I am using FOTRS btw)
that was to make strait south... now I turned round and went back and had 5* to starboard.
turned to 180 again manually and dive to PD and ran at 5 knots i noticed myself drift to a heading of 178 in 5 knotical miles.
Tell me theres no current.
Can you repeat the exact same experiment in different locations and compare "drifts"?


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Old 09-11-10, 12:57 PM   #19
Nisgeis
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Quote:
Originally Posted by Diopos View Post
What exaclty do you mean by " ...but the modelled 3D world you see is round..."?
The ships are placed as if they were on a sphere, but the sea is rendered as a flat plane. The result is that some ships appear to be sinking and pop up from the sea the closer you get.
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Old 09-11-10, 01:01 PM   #20
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I was just curious about even in real life since SH series is meant to be a simulation, I would think with a heavy enough cross wind you would actually drift off course unless (using trig, I remember doing these calculations) you headed into it at the right angle and speed
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Old 09-11-10, 01:10 PM   #21
Diopos
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Quote:
Originally Posted by Nisgeis View Post
The ships are placed as if they were on a sphere, but the sea is rendered as a flat plane. The result is that some ships appear to be sinking and pop up from the sea the closer you get.
Ok, but that's a trick or a shortcut, if you prefer, to simulate an horizon + earth's curvature effect. It is not a "real" 3D model. The ship is still on the "flatland" just a bit "sunk" .


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Old 09-11-10, 04:16 PM   #22
rein1705
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Quote:
Originally Posted by Diopos View Post
Can you repeat the exact same experiment in different locations and compare "drifts"?


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I'll do that tonight.
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Old 09-12-10, 07:51 AM   #23
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I dont appear to have a harbor anymore...

Steamed up to the Sulu Sea by choice and sank a german raider there. While hunting i made several course changes both surfaced and submerged and noticed that on different headings there were different results with the rudder positions. It seemed it i headed south east rudder wouldn't change from 0 but south would make for 5* to port and north 5* starboard until a storm blew in then the rudder was all over the place trying to maintain heading while surfaced. If i set rudder amidships it LOOKED like i was straying from my heading but i didnt observe much of a drift other than a few degrees, this being without TC.
It acted more like it had to do with the pitch and role of my sub than wind but underwater it'd have to of been some sort of current though i went as deep as 175 feet and noticed no change in strength. My rudder submerged would return to 0 as i changed back south east or to north west.
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