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MartinSax
03-18-2019, 03:05 PM
Dear All,

I am having a issue with a little situation, im trying to figure out a way around this:

I have a battleship model, along with turrets and gun etc..
Much like this video which gives a good example of what im trying to do:
https://www.youtube.com/watch?v=Rr0T3nBF7Wk

in rigging with, creating a target NULL, im taking the turret and barrel and creating a "Point at Target" selection. so i move the NULL and the urret will follow also etc..

This is fine for some guns, facing forward, however alot of the guns/turrets themselves which are facing in a opposite direction immediately do a 180 and face the opposite direction the target NULL.

I know i can edit this in the modeler, but this is time consuming and would now destroy the look of the actual model itself because turrets will all be messed up.

Is there any modifier or workaround i can apply in Layout to rotate the turret item when its at its point and target.

Kind regards,

Martin

RebelHill
03-18-2019, 04:17 PM
Use a bone located at the pivot point of the turret, and weight the gun to it.

Ztreem
03-18-2019, 06:14 PM
Unfortunately LW is missing options to set which axis to aim at target. You can do as rebelhill suggested but if you want to stay in layout you can parent the turret to a null that you set to aim at target and then you rotate the turret 180 degrees.

Kryslin
03-19-2019, 05:51 AM
I would use the rigged turret, like RH describes. Furthermore, I would use separate nulls for each turret's target. Not because each turret can fire at different targets (They can, but it's not easy to do), but because the aft turrets are limited in how far they can rotate by the superstructure. They can also depress only 5 degrees down, which sorely limits their close range; most can't hit something under 5000 yards with the main battery.

Ztreem
03-19-2019, 06:44 AM
I would use the rigged turret, like RH describes. Furthermore, I would use separate nulls for each turret's target. Not because each turret can fire at different targets (They can, but it's not easy to do), but because the aft turrets are limited in how far they can rotate by the superstructure. They can also depress only 5 degrees down, which sorely limits their close range; most can't hit something under 5000 yards with the main battery.

Why not have one target and limit the rotation of each turret?

hypersuperduper
03-19-2019, 08:56 AM
Why not have one target and limit the rotation of each turret?

While this might work for up and down tilt, it would result in wackiness if the target moves across the locked rotation regions, such as if the target was being tracked from one side of the ship to the other (across the superstructure). Better to have multiple targets even if they usually move together, and use a separate controller for the pitch. You could get really nerdy and tie the pitch to the distance to the target to simulate a firing arc. At that point of course you may as well forego point at target entirely and just use nodes. then you could use one target null and just solve for the superstructure with nodal logic.

Kryslin
03-19-2019, 03:19 PM
Why not have one target and limit the rotation of each turret?

Turrets amidships and aft usually have the superstructure of the ship in the way. Usually they are fired broadsides, so the entire battery can be brought to bear. For Wisconsin, you had a 65 degree arc broadsides, and a minimum range of 5000 yards. Anything closer got battered by 8" turrets.

Ztreem
03-19-2019, 04:37 PM
I was thinking of something like this.

144507

hypersuperduper
03-20-2019, 04:50 AM
I was thinking of something like this.

144507


If I had to guess, It looks like you have Heading Rotation limits on the turrets themselves, but also two hidden target nulls (one for each turret row) that follow the visible target null but are limited on the z position so they can't pass behind the turret row (in order to avoid the turrets snapping between max-min limit if the target passes behind them). Is that more or less right?

I messed around with a nodal setup for this sort of thing last night. Just one target, and all the turrets are handled nodally. It works, but is probably far too robotic to be useful for this kind of thing. On a real ship, If the target was beyond the rotation range of a turret, the crew would rotate the turret to the best position for where they believe target would come into range again, and that would depend on what the crew is planning to do, and intent can't really be handled with constraints like this, So it would probably still be better to have two targets: One for the fore and one for the aft guns so the animator can decide when the gunners stop trying to track a target that is out of range.
144508

MartinSax
03-20-2019, 05:36 AM
Use a bone located at the pivot point of the turret, and weight the gun to it.

This is a tad above my ability's and not quite sure about how to go about this, would you mind just being a little more basic for me :D sorry

https://www.youtube.com/watch?v=vMykI6rWGFY

I have followed this video, but i done have the Skelegons selection as in the video, so i feel like i might be missing something here...

EDIT:
I re-Scanned my plugins and now found it, so going to give this a go now and see how i get on.

Ztreem
03-20-2019, 07:30 AM
If I had to guess, It looks like you have Heading Rotation limits on the turrets themselves, but also two hidden target nulls (one for each turret row) that follow the visible target null but are limited on the z position so they can't pass behind the turret row (in order to avoid the turrets snapping between max-min limit if the target passes behind them). Is that more or less right?

144508

Exactly! I can't fool you. :)

It didn't work with just one target as the snapping desrtroyed the whole thing. This was the best I could do with just using point at target without any nodal logic or such. So the conclusion is one target isn't enough.
144509

Your test looks good.

MartinSax
03-22-2019, 02:43 PM
Use a bone located at the pivot point of the turret, and weight the gun to it.

Alright with a bit of work i have managed to get the turret working exactly as you said, however the barrels themselves refuse to adjust the same way, i have applied Bones hoping i could repeat the effect, but it seems this time round nothing seems to be working.

Using bones in the same vein simplytwists the barrels and warps them in a weird way rather then rotate the item (Barrels) itself.

MartinSax
03-22-2019, 03:15 PM
After witching off i had a brainwave and after turning on, i simply made the Bones the lentgh of the barrel and hey presto all seems to be working, just in case anyone tries to do this again, there is a final answer :D

Thanks everyone for the help in this!