Modelling of ocean currents/drift

iambecomelife · 09-18-05, 09:57 AM

Now that it's so easy to create clones of new units I'm planning on creating derelicts using the coastal merchant model. In other words I'll remove the unit's sensors, give it a top speed of zero, place it low in the water, and slap on some rust/fire/bomb damage textures. It will spawn randomly in midocean with a very wide possible radius, although I might also use it as a scripted object for beached shipwrecks in the scr layer.

Does anyone know if an object without propulsion will move slightly due to the effects of the ocean surface? I would prefer for the unit to be able to drift slowly through the 3d environment without making it propelled. If I give the unit a low top speed I'm pretty sure that it will cause the stack to start smoking, defeating the whole purpose of having an abandoned unit.

stljeffbb1 · 09-18-05, 11:07 AM

Cool idea! :|\

I can only give experiences I've had with extremely slow sinking ships, and I can say that on three different occasions, I've waited at least eight game hours in various locations watching over a sinking merchant and waiting for it to sink (this has usually been in a Type IIA and I'm out of torpedos!)....

Even though the effects are nice, the lapping of water into (and onto) the ships, it seems to me that the sinking ships (and also my U-Boat) never really moved in regards to ocean movement....also, my position, as far as I know, never changed on the map (I like to look often at the TDC map screen to get a better idea of what things look like, even though I play at 100% realism, and I still don't see too much...I simply like the close up protractor).

Hope this helps,

-Jeff

Hackett · 09-18-05, 11:10 AM

Units stopped in the water do drift with the simplistic water moddeling. Albiet at non realistic rates.
The drift is dependant on the current wind speed, and direction, but i dont believe the weather is modelled outside of the players "Bubble", in which case the target unit would just sit still until such a time when the player closes into range.

A better solution would be to clone a "Derelict Unit" as an environmental unit such as an iceberg, which one can control the speed and direction to better simulate "Actual" currents.

Col7777 · 09-18-05, 01:48 PM

CB did this in SH2, he had sunken ships as an underwater barricade to try and make it hard for those harbour raids, I tried to place some on the bottom using the 'Height' command but that didn't work, I also added too much weight thinking they may sink but they didn't.

ENtek-IO · 09-20-05, 08:25 PM

Well the model isnt so simplistic as it appears on first glance i think.
I observed that if you hit a dead in the water merchant at 90 degrees at the correct depht the ship is drifting away from the explosion at varying speeds.Best observed with a center hit.

Rubini · 09-20-05, 08:42 PM

iambecomelife,

Nice idea!

I will tell something related to my experience when I was making the HT mod:

I notice that all ships and mainly Aiuboats that are anchored just have very, very slow movement, so when you arrive to the port after few weeks many ship/aiuboats are in a slight different position. And - here is the better part - if you uncheck that 'Docked ship' box in mission editor, properties, the ship will move a lot (300m) away. I notice that when the ship have some speed (6 knots for example) and hit his last waypont this slow movement is still larger (after some days).

Hopes this help you.

Rubini.

iambecomelife · 09-20-05, 09:23 PM

That's good to know. I think I'll leave them stationary with spawn points in regions where heavy sinkings occurred historically - the Western Approaches, for example. They will disappear after a predetermined time (exit date function) so that these regions don't become unrealistically cluttered with ghost fleets.

Rubini · 09-20-05, 10:56 PM

And if you need to do some tests with traffic, etc just contact me.

Rubini.

HEMISENT · 09-21-05, 03:07 PM

Last night I completed a mission. Pulled into Wilhelmshaven about 0100 in heavy rain/high winds/horrible visibility. I always dock at the pier or in sub pen. to avoid a collision in the dark I pulled the boat next to a high seawall, shut everything down, came to full stop. I hit x64 time compression and watched on map view closeup as my boat moved back out away from seawall and about 300m closer to dock area. By daylight I was back in the middle of the channel much closer to the piers.

09-18-05, 09:57 AM	#1
iambecomelife Silent Hunter Join Date: Apr 2005 Posts: 4,706 Downloads: 300 Uploads: 0	Modelling of ocean currents/drift Now that it's so easy to create clones of new units I'm planning on creating derelicts using the coastal merchant model. In other words I'll remove the unit's sensors, give it a top speed of zero, place it low in the water, and slap on some rust/fire/bomb damage textures. It will spawn randomly in midocean with a very wide possible radius, although I might also use it as a scripted object for beached shipwrecks in the scr layer. Does anyone know if an object without propulsion will move slightly due to the effects of the ocean surface? I would prefer for the unit to be able to drift slowly through the 3d environment without making it propelled. If I give the unit a low top speed I'm pretty sure that it will cause the stack to start smoking, defeating the whole purpose of having an abandoned unit. __________________ https://www.facebook.com/WolvesoftheKaiser/

09-18-05, 11:07 AM	#2
stljeffbb1 Medic Join Date: Aug 2005 Location: Wisconsin USA Posts: 165 Downloads: 0 Uploads: 0	Cool idea! :\|\ I can only give experiences I've had with extremely slow sinking ships, and I can say that on three different occasions, I've waited at least eight game hours in various locations watching over a sinking merchant and waiting for it to sink (this has usually been in a Type IIA and I'm out of torpedos!).... Even though the effects are nice, the lapping of water into (and onto) the ships, it seems to me that the sinking ships (and also my U-Boat) never really moved in regards to ocean movement....also, my position, as far as I know, never changed on the map (I like to look often at the TDC map screen to get a better idea of what things look like, even though I play at 100% realism, and I still don't see too much...I simply like the close up protractor). Hope this helps, -Jeff __________________ SH3 Cloning Library: http://www.geocities.com/stljeffbb/CloningLibrary.html :rotfl:

09-18-05, 01:48 PM	#4
Col7777 Grey Wolf Join Date: Jun 2003 Location: Manchester UK Posts: 944 Downloads: 260 Uploads: 0	CB did this in SH2, he had sunken ships as an underwater barricade to try and make it hard for those harbour raids, I tried to place some on the bottom using the 'Height' command but that didn't work, I also added too much weight thinking they may sink but they didn't. __________________ Silent and Violent

09-20-05, 09:23 PM	#7
iambecomelife Silent Hunter Join Date: Apr 2005 Posts: 4,706 Downloads: 300 Uploads: 0	That's good to know. I think I'll leave them stationary with spawn points in regions where heavy sinkings occurred historically - the Western Approaches, for example. They will disappear after a predetermined time (exit date function) so that these regions don't become unrealistically cluttered with ghost fleets. __________________ https://www.facebook.com/WolvesoftheKaiser/

09-21-05, 03:07 PM	#9
HEMISENT Ace of the Deep Join Date: Feb 2003 Location: Northern Illinois Posts: 1,052 Downloads: 135 Uploads: 0	Last night I completed a mission. Pulled into Wilhelmshaven about 0100 in heavy rain/high winds/horrible visibility. I always dock at the pier or in sub pen. to avoid a collision in the dark I pulled the boat next to a high seawall, shut everything down, came to full stop. I hit x64 time compression and watched on map view closeup as my boat moved back out away from seawall and about 300m closer to dock area. By daylight I was back in the middle of the channel much closer to the piers. __________________ Nuke 'em till they glow!

09-18-05, 11:10 AM	#3
Hackett Mate Join Date: Apr 2005 Posts: 60 Downloads: 53 Uploads: 0	Units stopped in the water do drift with the simplistic water moddeling. Albiet at non realistic rates. The drift is dependant on the current wind speed, and direction, but i dont believe the weather is modelled outside of the players "Bubble", in which case the target unit would just sit still until such a time when the player closes into range. A better solution would be to clone a "Derelict Unit" as an environmental unit such as an iceberg, which one can control the speed and direction to better simulate "Actual" currents.

09-20-05, 08:25 PM	#5
ENtek-IO Bosun Join Date: May 2005 Location: Germany Posts: 62 Downloads: 41 Uploads: 0	Well the model isnt so simplistic as it appears on first glance i think. I observed that if you hit a dead in the water merchant at 90 degrees at the correct depht the ship is drifting away from the explosion at varying speeds.Best observed with a center hit.

09-20-05, 08:42 PM	#6
Rubini Ocean Warrior Join Date: May 2005 Location: São Paulo Brazil Posts: 2,728 Downloads: 132 Uploads: 0	iambecomelife, Nice idea! I will tell something related to my experience when I was making the HT mod: I notice that all ships and mainly Aiuboats that are anchored just have very, very slow movement, so when you arrive to the port after few weeks many ship/aiuboats are in a slight different position. And - here is the better part - if you uncheck that 'Docked ship' box in mission editor, properties, the ship will move a lot (300m) away. I notice that when the ship have some speed (6 knots for example) and hit his last waypont this slow movement is still larger (after some days). Hopes this help you. Rubini.

09-20-05, 10:56 PM	#8
Rubini Ocean Warrior Join Date: May 2005 Location: São Paulo Brazil Posts: 2,728 Downloads: 132 Uploads: 0	And if you need to do some tests with traffic, etc just contact me. Rubini.