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pdrake
11-17-2003, 03:31 PM
isn't there an auto bank function? i can't seem to find anything in the forums or the manual. thanks.

perry

mlinde
11-19-2003, 06:04 PM
Motion Options, controllers and Limits. Set it for Bank - Align to path, that usually works for me...

drclare
11-20-2003, 01:12 AM
There is no align to path option for bank, only for pitch and heading, why, i don't know.

mlinde
11-20-2003, 11:19 AM
I have it listed in my motion options...

drclare
11-20-2003, 02:18 PM
Huh, i don't, why do you think that is?

toby
11-20-2003, 10:27 PM
As far as I know align to path has never been available for bank.

If you think about it, if you're pointing a stick at something, twisting the stick makes no difference as to where it points.

I seem to remember some kind of auto - bank thing but I can't find it either. I don't think an Expression would be too hard - or maybe follower or cyclist could be used

mlinde
11-21-2003, 09:18 AM
Align path to bank makes perfect sense, which is why I don't understand how I have it and apparently others don't. When you do flight paths or waterborn craft paths, the vehicle follows the path (align-heading), and should rock/pitch/roll with curves and turns (align-pitch, align-bank). In addition, utilizing align-bank for medical animations (think cameras twisting down blood vessels) is another obvious use.

Just my 20 cents (inflation and all).

Lightwolf
11-21-2003, 09:29 AM
Originally posted by mlinde
Align path to bank makes perfect sense, which is why I don't understand how I have it and apparently others don't.
Check it again, it's there, but you can't activate it...
The same goes for point at target.
Cheers,
Mike

pdrake
11-21-2003, 09:45 AM
yeah, it's there, just grayed out. i don't understand either. maybe it will be available in 8. i might be thinking of electric image, i'm sure there is an auto bank in it. maybe newtek can comment on this.

lonestar1
11-21-2003, 01:53 PM
Originally posted by mlinde
Align path to bank makes perfect sense, which is why I don't understand how I have it and apparently others don't. When you do flight paths or waterborn craft paths, the vehicle follows the path (align-heading), and should rock/pitch/roll with curves and turns (align-pitch, align-bank).

First, you need to look at the geometry. When Lightwave aligns the Pitch/Heading to the flight path at a given point, it is making the Pitch/Heading match a line tangent to the flight path at that point. The Bank angle is the rotation about the axis that Lightwave is aligning, so changing the Bank angle has no effect on alignment.

Second, if you made the bank angle vary as a function of the flight path, you would not get a realistic aircraft motion. When an aircraft turns, the pilot rolls the plane to the desired Bank angle. Then, he holds that angle constant throughout the turn. When he reaches the desired heading, he straightens out the wings and flies level. In a coordinated turn, the Bank angle determines the tightness or radius of the turn. If the pilot doesn't hold it constant during the turn, the radius will vary and he will get a sloppy turn. You need to understand what the aircraft is doing; you can't expect Lightwave do it for you. At least, not until someone writes a plug-in flight simulator.

drclare
11-21-2003, 03:22 PM
Well, yeah it is there, but grayed out. I don't see why it is not there though. I use to use Strata 3D pro, which was a terrible program compared to lightwave, but it had an auto bank function that worked very well, i don't think it should be a hard feature to imlement at all. And why one person here has the feature available to him, and no one else, is a total mystery. Mlinde, are you using 7.5c? I am on 7.5b and don't have it, and before i got the b update i didn't have it either.

mlinde
11-21-2003, 04:56 PM
Well rub my face in mud and call me stupid. I didn't actually test the function, I just knew it was there. And yes, you all are correct, Align to Path (Bank) and Point at Target (Bank) are not actually ever selectable.

:rolleyes:

feeling fairly stupid right now. Just gonna go over to a corner here and sit...quietly...

Beamtracer
11-22-2003, 05:40 PM
Actually, "Autobank" would be a really useful feature request. Newtek could place it in Lightwave's motion options.

It could behave as if there was a large imaginary pendulum hanging underneath your object which swings out when your object turns a corner, causing the object to bank.

The Autobank feature could come with a Weight control to control the force and influence of this imaginary pendulum.

How does that sound?

toby
11-22-2003, 08:05 PM
I think there's too much variation in how things bank to make a simple plug-in that's better than hand-keying it, to take lonestar's example airplanes are banked manually before turning, and notice they can bank without turning. ( they can even turn without banking, it's just inefficient ) - cars on the other hand bank in the opposite direction, during the turn - and the angle depends on a combination of the speed and sharpness of the turn.

A Car and Plane dynamics engine are what we need - now that would be cool!

Beamtracer
11-23-2003, 12:55 PM
Here's some extra controls our Autobank feature could have:

•Y-axis control. Set the weight to positive Y axis for a car (which is top heavy) or negative Y axis for an aircraft (which tilts a bit like it's bottom heavy).

•Look ahead distance. If you're animating an aircraft, set it to look ahead so it anticipates the turn.

Well, it may not be perfect. I'm sure a lot of aircraft enthusiasts would want to manually keyframe everything to make it more realistic.

However, I think in many banking scenarios (especially camera bank) an automatic feature would suffice, and accomplish it much quicker.

toby
11-23-2003, 01:27 PM
I tried to make an expression but I don't know to get the Velocity value from the Heading - if you used that to affect the bank value I think it could work

lonestar1
11-24-2003, 02:29 AM
Originally posted by toby
A Car and Plane dynamics engine are what we need - now that would be cool!

It already exists (or at least it did). It's called ReelMotion. You can find some info at www.reelmotion.com, but the web site looks like it hasn't been updated in about three years. I wouldn't be surprised to find it doesn't work with OSX.

lonestar1
11-24-2003, 02:50 AM
Originally posted by Beamtracer
Here's some extra controls our Autobank feature could have:

•Y-axis control. Set the weight to positive Y axis for a car (which is top heavy) or negative Y axis for an aircraft (which tilts a bit like it's bottom heavy).

How a car tilts is not simply a function of how top-heavy it is. You need to take into account the design of the suspension -- the stiffness of the springs, etc.


•Look ahead distance. If you're animating an aircraft, set it to look ahead so it anticipates the turn.

Well, it may not be perfect.

No, in fact, it will be completely wrong. To get realistic motion, you need to have an understanding of the physics, or at least the timing, involved.


However, I think in many banking scenarios (especially camera bank) an automatic feature would suffice, and accomplish it much quicker.

I don't think I've ever seen a tripod with an "autobank" feature. Cinematographers do that manually. How do you write a mathematical function to simulate an artistic choice made by the cameraman? Or else the bank is due to the motion of a camera vehicle, in which case the laws of physics again come into play.

Lightwave may be a wonderful tool, but it does not relieve animators from the necessity of being animators.

zander
11-24-2003, 08:27 AM
Yes, I was just searching for this feature and couldn't find it. (I'm doing a camera flythrough of a city scene.)

It doesn't seem like it would be too hard to create something in Lscript. (But, I don't have time to mess with it.) Think of it as a pendulum/spring system. The camera is the "anchor" and a null point below the camera would be pendulum...

toby
11-24-2003, 10:57 AM
"I don't think I've ever seen a tripod with an "autobank" feature. Cinematographers do that manually."

One thing we like about 3D is that we don't have to stick to the limitations of real life.

I flew the camera thru a motorcycle engine, I don't think tripods have that feature either -

lonestar1
11-24-2003, 12:30 PM
Originally posted by toby
"I don't think I've ever seen a tripod with an "autobank" feature. Cinematographers do that manually."

One thing we like about 3D is that we don't have to stick to the limitations of real life.

I flew the camera thru a motorcycle engine, I don't think tripods have that feature either -

A wonderful argument that can be used to justify anything you do in computer graphics.

Yes, you can use a nonsense expression, which will cause your camera to behave like it's out of control and move in ways no cameraman would in the real world.

There are good reasons why real-world cameramen limit their movements, however. It's generally considered bad form to have the audience running from the theater to the restrooms because you've made them seasick.

toby
11-24-2003, 02:22 PM
yea Whatever

I guess were not allowed to do non-realistic camera animation. I guess Fight Club sucked, because real cameras can't go through walls and sidewalks or pan around stove burners.

zander
11-24-2003, 03:23 PM
Here's an Lscript I wrote to do some primitive auto-banking. It subtracts current heading from heading 'N' frames in the future/past, then multiply/divides the difference by a 'ratio'. You can set the 'Look Ahead Frames' and the 'Ratio' from the UI.

Use at your own disgression, I won't be held liable for seasick audience members. :P

There's still work to be done! Sometimes the banking isn't as smooth as it should be. This could be solved by doing some averaging (instead of just looking 30 frames head...) Please post any 'good' modifications you make. :)

toby
11-24-2003, 03:32 PM
Man that's cool! - wish I could learn to Lscript - no time

zander
11-24-2003, 03:40 PM
Yeah, this is actually my first 'Layout' Lscript. I did a couple of 'modeler' Lscripts last week (and that was a first too.) :)

zander
11-24-2003, 08:56 PM
I've posted an updated version of the Lscript here (http://vbulletin.newtek.com/showthread.php?s=&threadid=14280). I thought I should quit hijacking this thread. :)

lonestar1
11-24-2003, 11:29 PM
Originally posted by toby
yea Whatever

I guess were not allowed to do non-realistic camera animation. I guess Fight Club sucked, because real cameras can't go through walls and sidewalks or pan around stove burners.

The Fight Club cinematographers worked very hard to get cameras to move the way they wanted. They didn't just fly through walls at random because someone wrote expressions he didn't understand, then tried to justify the result as "artistic."

Irrelevant, uninformed foreign policy comments deleted.

toby
11-25-2003, 01:06 AM
"I think there's too much variation in how things bank to make a simple plug-in that's better than hand-keying it"

My words.

I never justified slapping on a plug-in and letting it do the work. Somebody wanted Auto-bank and instead of looking down my nose at them, I thought I'd try to do an expression, and btw thanks for the encouragement - "someone wrote expressions he didn't understand"

You're being too rigid. We don't all work at Blue Sky or Digital Domain, we're not all trying for photorealism, we don't all work on a team that can specialize.

There's nothing wrong with trying out AutoBank.
---------------------------------

I will not be silent when my leader behaves like Hitler, for profit, in my name and at my expense.

pdrake
11-25-2003, 12:09 PM
i'm the one who asked about auto bank. i know that there is this function available in electric image (which i own) and strata (which i own, but don't use anymore). i just wondered about lightwave having it. i guess some lightwave users are too uptight and focused on realism to think that their x-wing fighter can't be told how to bank by a computer. i can't understand how these other packages could have wasted their time writing functions that make no sense and are completely ignorant of how things work. dumbasses.

thanks for the script toby, i for one appreciate your effort. i'm still trying to figure out how it works. could you post a sample?

perry

p.s. sorry, didn't mean to start anything.

lonestar1
11-25-2003, 06:49 PM
Originally posted by toby
I will not be silent when my leader behaves like Hitler, for profit, in my name and at my expense.

Sigh. Does the Left have to turn every public forum into a venue for America bashing?

Do you have any idea who Hitler was, what he did, and how he was removed from power (the same way Saddam Hussein was removed from power)?

I blame the public school system. :-)

Beamtracer
11-25-2003, 07:48 PM
Originally posted by lonestar1
"How do you write a mathematical function to simulate an artistic choice made by the cameraman?"

"Yes, you can use a nonsense expression, which will cause your camera to behave like it's out of control and move in ways no cameraman would in the real world."

"The Fight Club cinematographers... ...didn't just fly through walls at random because someone wrote expressions he didn't understand"
Lonestar, your posts are getting tiresome. There's no point objecting to someone's political comments when you write more political comments yourself.

There's also no point complaining about people using an automated bank plug-in just because you don't like it. If you don't like it, don't use it. Stay out of this thread and then you won't have to think about it.

Calling the plug-in "nonsense" and inferring the plug-in writer "doesn't understand" the expression he is writing is pretty counter productive to anything.

I'd like to congratulate those working on making an Autobank plug-in / Lscript. It's a wonderful idea, and many people will enjoy using it.

toby
11-25-2003, 08:03 PM
ah, it was Zander that made the Lscript - still haven't had time to try it

----------------------------
Bashing a corrupt leader is not America bashing, my sig is to coax people into private conversations. There are dozens more things to complain about this administration, but the invasion of other countries is what's globally important, therefore the reference to Hitler.

toby
11-25-2003, 08:52 PM
COOL !
When used with "align to path" it works nicely -

Thanks Zander!

(change ".txt" to ".lws" - lets see if this works)

zander
11-25-2003, 09:28 PM
Thanks Toby, I was beginning to wonder if anyone would try it out. :) Your scene file looks good! (I noticed that "align to path" does some weird motions sometimes... I thought it was my script at first, but the "bumps" were still there after I removed the script.)

Also, I've started a new thread in the "Lscripts" area of the Forum (because this thread was beginning to suck.) I posted a new version of the Lscript there (and I've also attached the same version below...) You can download it from here:

http://vbulletin.newtek.com/showthread.php?s=&threadid=14280

There are 2 big improvements:

1) I added "sampling" so that really sharp turns can be handled correctly.

2) I added the necessary function to load and save the "Look Ahead" and "Ratio" values in the LWS file. (Otherwise it reverts to the default value...)

toby
11-25-2003, 10:36 PM
thanks big Z - yea sorry about the arguing

It seems to work totally different without align to path on (I even keyframed the heading with a-t-p on then removed it) - it banks a lot less and often does it at the wrong place

Don't get me wrong, even with just a-t-p it's sweet! Looks more useful than I thought, and it's way cool/fun.

pdrake
11-25-2003, 11:19 PM
that's just stupid and i'm sure you don't understand it.

i'll try it tomorrow.:p