RE: [Flightgear-devel] Eye candy

2004-02-19 Thread Vivian Meazza


 Vivian Meazza wrote
 
> 
>  Andy Ross wrote
>  
> > Vivian Meazza wrote:
> > > I think it should work, and it _looks_ as if it does:
> > certainly when
> > > you browse internal properties it looks right, but I can't set the
> > > second [1] tank to zero.
> > 
> > I'm still fuzzy.  Do you mean that you can't set the property
> > to zero at all, or that the property goes to zero but YASim 
> > doesn't do the right thing?
> > 
> > I agree, the configuration looks correct to me.
> > 
> > Andy
> > 
> 
> I've now done some more testing. I've now set up my keyboard 
> so that I can adjust the property - all works. However, the 
> weight property of the second tank cannot be set via the 
> property browser. The problem _seems_ to lie in the 
> Properties Browser.
> 
> Now we need to be able to set the fuel property ...
> 
> Vivian 


I've now got a model working, sort of, with drop tanks. At the moment it's
only partly realistic, because the fuel can't be managed correctly yet. I've
modelled the pylons as vertical stabilisers and the droptanks as weights.
Separation looks OK from the cockpit view, and reasonable from external
views, provided that the aircraft is straight and level.

I note that when full fuel tanks are jettisoned, there isn't much sign of
nearly a ton being released from the aircraft. I was looking for at least a
flick from the accelerometer. Does it happen too fast for the instrument to
pick it up? There is a detectable, but small, trim change as I would expect.

Regards

Vivian

 




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RE: [Flightgear-devel] Eye candy

2004-02-17 Thread Vivian Meazza


 Andy Ross wrote
 
> Vivian Meazza wrote:
> > I think it should work, and it _looks_ as if it does: 
> certainly when 
> > you browse internal properties it looks right, but I can't set the 
> > second [1] tank to zero.
> 
> I'm still fuzzy.  Do you mean that you can't set the property 
> to zero at all, or that the property goes to zero but YASim 
> doesn't do the right thing?
> 
> I agree, the configuration looks correct to me.
> 
> Andy
> 

I've now done some more testing. I've now set up my keyboard so that I can
adjust the property - all works. However, the weight property of the second
tank cannot be set via the property browser. The problem _seems_ to lie in
the Properties Browser.

Now we need to be able to set the fuel property ...

Vivian 



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RE: [Flightgear-devel] Eye candy

2004-02-17 Thread Vivian Meazza


 Andy Ross
> 
> 
> Vivian Meazza wrote:
> > I think it should work, and it _looks_ as if it does: 
> certainly when 
> > you browse internal properties it looks right, but I can't set the 
> > second [1] tank to zero.
> 
> I'm still fuzzy.  Do you mean that you can't set the property 
> to zero at all, or that the property goes to zero but YASim 
> doesn't do the right thing?
> 
> I agree, the configuration looks correct to me.
> 

I can't set the property of the second tank to zero. So far as I can see,
Yakima is doing the right thing.

V



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Re: [Flightgear-devel] Eye candy

2004-02-17 Thread Andy Ross
Vivian Meazza wrote:
> I think it should work, and it _looks_ as if it does: certainly when
> you browse internal properties it looks right, but I can't set the
> second [1] tank to zero.

I'm still fuzzy.  Do you mean that you can't set the property to zero
at all, or that the property goes to zero but YASim doesn't do the
right thing?

I agree, the configuration looks correct to me.

Andy

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RE: [Flightgear-devel] Eye candy

2004-02-17 Thread Vivian Meazza


> Andy Ross
> 
> Vivian Meazza wrote:
> > Yes, this problem was interesting. I set up 2 weights thus:
> >
> > /yasim/weights/tank-100gal-lbs[0] /yasim/weights/tank-100gal-lbs[1]
> 
> Are you sure you got the  definition right in the 
> YASim configuration file?  The property definitions look 
> fine, but they're only half the problem.  You need to tell 
> YASim to read those properties, and where to put the mass 
> value that it finds.
> 

Yes, pretty certain, coded thus:






YASim didn't complain anyway, and the model flies just fine.

My analysis is that the problem lies here:


   
 45
 150 
--> 150  
   
 

I think it should work, and it _looks_ as if it does: certainly when you
browse internal properties it looks right, but I can't set the second [1]
tank to zero.

Regards

Vivian 




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Re: [Flightgear-devel] Eye candy

2004-02-17 Thread Andy Ross
Vivian Meazza wrote:
> Yes, this problem was interesting. I set up 2 weights thus:
>
> /yasim/weights/tank-100gal-lbs[0]
> /yasim/weights/tank-100gal-lbs[1]

Are you sure you got the  definition right in the YASim
configuration file?  The property definitions look fine, but they're
only half the problem.  You need to tell YASim to read those
properties, and where to put the mass value that it finds.

Andy

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RE: [Flightgear-devel] Eye candy

2004-02-17 Thread Vivian Meazza


 Lee Elliott wrote
 
> Just to help confuse things a little, j/k are for spoilers, 
> iirc, but as 
> speed-brakes aren't supported in YASim (yet;) I've used the 
> spoiler control. 

Kludged that one by using an extra, low lift, high drag flap on the
horizontal stabiliser in the Hunter. CTRL B toggles it. Not neat, but works
well enough.  I look forward to its proper implementation idc.

Regards 

Vivian



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RE: [Flightgear-devel] Eye candy

2004-02-17 Thread Vivian Meazza


> Andy Ross
 
> Vivian Meazza wrote:
> > I've just done some proof-of-principle work on drop tanks 
> with YASim. 
> > I set up some weight elements for the pylons and for the 
> dry weight of 
> > the tanks, and some fuel tanks to match. [...]
> > However, the bad news is that I can't set _one_ of the drop tank
> > weights to zero (odd that), and none of the tank fuel contents.
> 
> YASim doesn't currently support setting fuel tank contents, 
> though, it treats the /sim/consumables/ properties as 
> writables only; it doesn't read them.  This wouldn't be too 
> hard to fix.

So I discovered. I believe we need this function if we are to simulate drop
tanks correctly, unless you can think of another way. We also need to be
able to control tank usage, so that we can use drop tanks first then
internal tanks. I haven't fully investigated, but I presume that this is not
possible right now.

> 
> I'm not clear on the problem you are having with the weight 
> tag.  You can associate any property with the weight; just 
> use different names and you can set them in any combination.
> 

Yes, this problem was interesting. I set up 2 weights thus:

/yasim/weights/tank-100gal-lbs[0]
/yasim/weights/tank-100gal-lbs[1]

By using


   
 45
 150 
   150 
   
 

I used 'browse internal properties' to access both so I could test the
operation of setting to zero to simulate jettison. Both  entries _look_ OK,
however, I could set /././...-lbs[0] to zero, but not the second tank [1]. I
was trying to conform with what I saw as the convention for other tanks etc.
I was being too subtle, I suppose, if I call them totally different names,
it'll work fine. In fact there's no need for it unless I set up a failure
mode in the future

As I said - interesting, but I can work around it. Would be a neat way of
doing it, and it would conform to the way of doing things in YASim.

Grateful for your help

Vivian









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Re: [Flightgear-devel] Eye candy

2004-02-16 Thread Lee Elliott
On Monday 16 February 2004 22:12, Martin Spott wrote:
> "Vivian Meazza" <[EMAIL PROTECTED]> wrote:
> > However, the bad news is that I can't set _one_ of the drop tank weights
> > to zero (odd that), and none of the tank fuel contents. I was planning to
> > use keys j/J/CTRLJ for jettison inner/outer/all.
>
> As memory serves (late evening  ;)  j/k are used for speed brakes on
> some aircraft,
>
> Martin.

Just to help confuse things a little, j/k are for spoilers, iirc, but as 
speed-brakes aren't supported in YASim (yet;) I've used the spoiler control 
input for what is effectively the speed brake function.  Get's even more 
interesting with the YF-23 as it's 'speed-brake' is opposite deflection of 
flaps and ailerons, controlled by the spolier control:)

LeeE


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Re: [Flightgear-devel] Eye candy

2004-02-16 Thread Andy Ross
Vivian Meazza wrote:
> I've just done some proof-of-principle work on drop tanks with
> YASim. I set up some weight elements for the pylons and for the dry
> weight of the tanks, and some fuel tanks to match.
> [...]
> However, the bad news is that I can't set _one_ of the drop tank
> weights to zero (odd that), and none of the tank fuel contents.

YASim doesn't currently support setting fuel tank contents, though, it
treats the /sim/consumables/ properties as writables only; it doesn't
read them.  This wouldn't be too hard to fix.

I'm not clear on the problem you are having with the weight tag.  You
can associate any property with the weight; just use different names
and you can set them in any combination.

Andy

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RE: [Flightgear-devel] Eye candy

2004-02-16 Thread Vivian Meazza
 Martin Spott
> 
> "Vivian Meazza" <[EMAIL PROTECTED]> wrote:
> 
> > However, the bad news is that I can't set _one_ of the drop tank 
> > weights to zero (odd that), and none of the tank fuel 
> contents. I was 
> > planning to use keys j/J/CTRLJ for jettison inner/outer/all.
> 
> As memory serves (late evening  ;)  j/k are used for speed 
> brakes on some aircraft,
> 

So I believe, but CTRL B is in the documentation for that function - so I
use it.

Vivian



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Re: [Flightgear-devel] Eye candy

2004-02-16 Thread Martin Spott
"Vivian Meazza" <[EMAIL PROTECTED]> wrote:

> However, the bad news is that I can't set _one_ of the drop tank weights to
> zero (odd that), and none of the tank fuel contents. I was planning to use
> keys j/J/CTRLJ for jettison inner/outer/all.

As memory serves (late evening  ;)  j/k are used for speed brakes on
some aircraft,

Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
--

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RE: [Flightgear-devel] Eye candy

2004-02-16 Thread Vivian Meazza


 Josh Babcock wrote
 
> Or just have a command that creates an object at a certain 
> point with a 
> certain velocity vector and orientation.
> Josh
> 
> Erik Hofman wrote:
> 
> > Andy Ross wrote:
> >
> >> Running it under a separate "FDM" handler is something 
> that the C++ 
> >> code just doesn't support yet, though. It's probably not hugely 
> >> difficult to make work, though.
> >
> >
> >
> > Thinking about:
> >
> > 1. inherit the main FDM's moments and forces
> > 2. transpose them to the appropriate location.
> > 3. Use that as the initial values for your ballistic FDM.
> >
> > Erik

I've just done some proof-of-principle work on drop tanks with YASim. I set
up some weight elements for the pylons and for the dry weight of the tanks,
and some fuel tanks to match. My plan was to set the drop tank and the fuel
they contain to zero on jettison, leaving the pylons in situ.  The good news
is that that YASim continues to converge, so I'm over the first hurdle.
However, the bad news is that I can't set _one_ of the drop tank weights to
zero (odd that), and none of the tank fuel contents. I was planning to use
keys j/J/CTRLJ for jettison inner/outer/all.

I can do a work around for the tanks - using the same weight twice - and
that will do for now, but I won't be able in the future to simulate an
asymmetric situation in the event of one tank failing to separate. I also
need to be able to hand off the remaining contents of the fuel to the drop
tank on jettison when we have a child fdm in addition to the items listed
above.

Am I adopting the right approach? If I am, then I conclude that there is no
point in proceeding further unless I can set the tank contents to zero. With
that enabled I can produce a reasonable simulation pending the
implementation of a child fdm in YASim. I haven't been able to tackle JBSim
yet.

Advice would be welcome.

As a matter of interest, the list of controls list 'armament controls'. Are
these implemented? If they are, then it would make sense to use them to
control drop tanks. But it's no problem if they aren't.

Regards

 
Vivian Meazza  



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Re: [Flightgear-devel] Eye candy - Wing Bending

2004-02-15 Thread Jim Wilson
Erik Hofman said:
 
> I think the tweening support should be added for this. Then you would 
> have as many wing sections as you define in the 3d model.
> 
> You would basically have two different version of the same object bot 
> defined at their maximum and the tweening code will take care of the rest.
> 
> I think the tweening code will be fast enough.
> 
> To be prepared for the future you could already add three versions of 
> the wing: a max positive and max negative bend version which should be 
> turned off in the animations file for now, and a normal version which 
> should be turned off when tweening is implemented.
> 
> I haven't looked at tweening yet, but since plib already supports it, 
> implementing it into the SimGear animation code would probably be not 
> much of a problem.
> 

Probably not too much, but it would be a little different than the other
animations we have.  Normally the animations are processed as a callback on a
particular node.  For the tween it seems like you'd have to start with to
reference nodes the generated or updated a third.  I'm not sure what is the
best way to structure that.

Best,

Jim


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Re: [Flightgear-devel] Eye candy

2004-02-15 Thread Mathias Fröhlich
On Samstag, 14. Februar 2004 22:33, Jon Berndt wrote:
> One feature in JSBSim that I began and have not yet finished (pending other
> things) is a parent/child capability. You can (for instance) load a Mk82 on
> an F-16 and the physical effects of the Mk82 will affect the F-16. The
> position is based on the position of the parent, and so is the orientation.
> However, the Mk82 position is not integrated, it always has a position
> based on the parent, UNTIL it is released. Then, the EOM begins integrating
> and the flyout is physics based.
>
> The child objects are each their own individual JSBSim objects in their own
> right, and each could be loaded and flown by itself. The JSBSim executive
> is sort of recursive in this way. Each would be addressable in a way that I
> think Tony set up with Properties, but I can't recall what it is.
>
> Technically, it is also possible for each droppable piece to have its own
> propulsion and flight control system, too. The possiblities there are quite
> broad.
Sounds interresting.
I have this in mind now for my timestepping changes.
As I told you before in a private mail, many ideas for something like that in 
my head ...

Greetings

Mathias

-- 
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Re: [Flightgear-devel] Eye candy - Wing Bending

2004-02-15 Thread Erik Hofman
kreuzritter wrote:

Upgrade: 
And how to simplify it and integrate it nicly into flightgear so that it is 
still fast enough.
I also gave up the idea of limiting the number of wing sections to only 4, 
imho this should depend on the type of airplane, so i thought about
a dynamic range of wing sections that can be adjusted to the type of airplane.


I think the tweening support should be added for this. Then you would 
have as many wing sections as you define in the 3d model.

You would basically have two different version of the same object bot 
defined at their maximum and the tweening code will take care of the rest.

I think the tweening code will be fast enough.

To be prepared for the future you could already add three versions of 
the wing: a max positive and max negative bend version which should be 
turned off in the animations file for now, and a normal version which 
should be turned off when tweening is implemented.

I haven't looked at tweening yet, but since plib already supports it, 
implementing it into the SimGear animation code would probably be not 
much of a problem.

Erik

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Re: [Flightgear-devel] Eye candy

2004-02-15 Thread Matevz Jekovec




Andy Ross wrote:

  Lee Elliott wrote:
  
  
I think drop tanks would be feasible but it would need some thinking
about:)

The fun bit will be counteracting the a/c manuevours after the tank
has dropped so it falls straight even though the a/c may be climbing
and banking.

  
  
This is more of a code architecture issue.  Once something has left
the aircraft, it ought be be handed to a simple "ballistics FDM" or
somesuch.  Making it "disappear" from the aircraft model is as simple
as adding a select animation and can be done right now.  And you can
set the weight tag to zero to get the FDM behavior correct.

Running it under a separate "FDM" handler is something that the C++
code just doesn't support yet, though.  It's probably not hugely
difficult to make work, though.

Andy

  

The same option should then be used for all the weapons as well; let it
be dumb bombs, rockets or missles. They will all start with certain
vector of speed and some point in space and will then change it through
time (effect of force of gravity and weapon's propulsion). The tankers
should be treated like normal dumb bombs.


-  Matevz


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Re: [Flightgear-devel] Eye candy - Wing Bending

2004-02-14 Thread kreuzritter2000
On Sunday 15 February 2004 08:39, [EMAIL PROTECTED] wrote:
>
> I am working on wing bending too but i am still on working
> out how a physical model of this wing bending would look like in real life.

Upgrade: 
And how to simplify it and integrate it nicly into flightgear so that it is 
still fast enough.
I also gave up the idea of limiting the number of wing sections to only 4, 
imho this should depend on the type of airplane, so i thought about
a dynamic range of wing sections that can be adjusted to the type of airplane.

This means: 
A glider would need more wing sections than a space shuttle.


Best Regards,
  Oliver C.


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Re: [Flightgear-devel] Eye candy - Wing Bending

2004-02-14 Thread kreuzritter2000
On Saturday 14 February 2004 22:10, Josh Babcock wrote:
> Actually, I was thinking of playing with wing flexing with the model
> that I am working on now, but I figured that I already had too many
> bells and whistles.  I was going to divide each wing into about four
> sections and put them into a tree-like structure with all the engines,
> etc hanging off the group objects with the wing segments.  Then you can
> rotate the inner group by a factor of the g-load, and again for each
> section.  The effect should be cumulative at the tip, but I never tested
> it.  There might be a problem with the pivot points not matching up when
> the wing is flexed though, you might have to do some translating too.
> This would be a great feature if anyone ever modeled the Voyager.  Then
> the trick would be modeling the wingtip scrapes and deleting the wingtip
> lights, just like in real life!
> Josh
>

So you read my discussion on irc.flightgear.org 2-3 weeks ago about my wing 
bending idea?

I am working on wing bending too but i am still on working
out how a physical model of this wing bending would look like in real life.


Best Regards,
 Oliver C.




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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Josh Babcock
Oh, yeah, that too.
Josh
Erik Hofman wrote:

Josh Babcock wrote:

Or just have a command that creates an object at a certain point with 
a certain velocity vector and orientation.


I think you still need the moments to get a decent traject match.




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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Erik Hofman
Josh Babcock wrote:
Or just have a command that creates an object at a certain point with a 
certain velocity vector and orientation.
I think you still need the moments to get a  decent traject match.

Erik

Josh

Erik Hofman wrote:

Andy Ross wrote:

Running it under a separate "FDM" handler is something that the C++
code just doesn't support yet, though. It's probably not hugely
difficult to make work, though.
Thinking about:

1. inherit the main FDM's moments and forces
2. transpose them to the appropriate location.
3. Use that as the initial values for your ballistic FDM.
Erik
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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Erik Hofman
Lee Elliott wrote:

Agreed, a simple 'ballastics' FDM would be a far better solution, but then 
someone's got to design & code it.
Which reminds me, an FDM (Yasim, UIUC/LaRCsim or JSBSim) could spawn an 
AIModel object which has (simple) ballistic trajectory support.

Erik

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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Josh Babcock
Or just have a command that creates an object at a certain point with a 
certain velocity vector and orientation.
Josh

Erik Hofman wrote:

Andy Ross wrote:

Running it under a separate "FDM" handler is something that the C++
code just doesn't support yet, though. It's probably not hugely
difficult to make work, though.


Thinking about:

1. inherit the main FDM's moments and forces
2. transpose them to the appropriate location.
3. Use that as the initial values for your ballistic FDM.
Erik

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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Erik Hofman
Andy Ross wrote:

Running it under a separate "FDM" handler is something that the C++
code just doesn't support yet, though.  It's probably not hugely
difficult to make work, though.


Thinking about:

1. inherit the main FDM's moments and forces
2. transpose them to the appropriate location.
3. Use that as the initial values for your ballistic FDM.
Erik

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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


Jon Berndt
> 
> >
> > Sounds VERY good. I'm sure you'll get round to it in due course.
> >
> > Vivian
> 
> Did I say that? ;-)
> 
> I think I may have a few weeks this summer *alone*. That's 
> got "opportunity" written all over it.
> 

Excellent. But summer is for real flying.

Vivian



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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


 Andy Ross wrote
> 
> Lee Elliott wrote:
> > I think drop tanks would be feasible but it would need some thinking
> > about:)
> >
> > The fun bit will be counteracting the a/c manuevours after the tank 
> > has dropped so it falls straight even though the a/c may be 
> climbing 
> > and banking.
> 
> This is more of a code architecture issue.  Once something 
> has left the aircraft, it ought be be handed to a simple 
> "ballistics FDM" or somesuch.  Making it "disappear" from the   
> aircraft model is as simple as adding a select animation and 
> can be done right now.  And you can set the weight tag to 
> zero to get the FDM behavior correct.
> 
> Running it under a separate "FDM" handler is something that 
> the C++ code just doesn't support yet, though.  It's probably 
> not hugely difficult to make work, though.
> 

Under YASim, I suppose that we would need the pylon - a fuselage object? A
drop tank - a weight object and its contents -  a tank object. In the Hunter
an explosive charge ensured clean separation; that would be nice to model,
then the tank would follow the separate FDM. There's this weekends challenge
;-)

Vivian



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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Jon Berndt
> Actually, I was thinking of playing with wing flexing with the model
> that I am working on now, but I figured that I already had too many
> bells and whistles.  I was going to divide each wing into about four
> sections and put them into a tree-like structure with all the engines,
> etc hanging off the group objects with the wing segments.  Then you can
> rotate the inner group by a factor of the g-load, and again for each
> section.  The effect should be cumulative at the tip, but I never tested
> it.  There might be a problem with the pivot points not matching up when
> the wing is flexed though, you might have to do some translating too.
> This would be a great feature if anyone ever modeled the Voyager.  Then
> the trick would be modeling the wingtip scrapes and deleting the wingtip
> lights, just like in real life!
> Josh

This would be very cool. Though adding general-case aeroelastic effects for
aircraft would be pretty tedious, to say the least. A simple approximation
could add a nice touch of realism.

Jon


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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Jon Berndt
>
> Sounds VERY good. I'm sure you'll get round to it in due course.
>
> Vivian

Did I say that? ;-)

I think I may have a few weeks this summer *alone*. That's got "opportunity"
written all over it.

Jon


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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Josh Babcock
Actually, I was thinking of playing with wing flexing with the model 
that I am working on now, but I figured that I already had too many 
bells and whistles.  I was going to divide each wing into about four 
sections and put them into a tree-like structure with all the engines, 
etc hanging off the group objects with the wing segments.  Then you can 
rotate the inner group by a factor of the g-load, and again for each 
section.  The effect should be cumulative at the tip, but I never tested 
it.  There might be a problem with the pivot points not matching up when 
the wing is flexed though, you might have to do some translating too.  
This would be a great feature if anyone ever modeled the Voyager.  Then 
the trick would be modeling the wingtip scrapes and deleting the wingtip 
lights, just like in real life!
Josh

Lee Elliott wrote:

On Friday 13 February 2004 22:27, Jon S Berndt wrote:
 

Any chance of modeling wingtip vortices (when CL is high enough above
some threshhold) and rocket engine exhaust?
:-)

Jon
   

I've thought about trying this but I think it could only be really effective 
in level flight.  As soon as you start banking the 'end' of whatever trail 
you're simulating will rotate (echos of the VRP issues:).

For a very short trail this might not be noticable but for longer ones I think 
it's a bit of a show stopper.

It would be possible to include curved trails in the model, and the select 
anim function could be used to select the appropriate model object, but then 
you'd need a wide range of trail objects.

At first glance, this doesn't seem too bad, but then I think you'd really need 
several versions of each trail type so that you could switch between them to 
give the impression that the trail is changing throught time.

Hmm...   I don't think I've explained that bit very well...

Consider an a/c in stable level flight where votices are being generated from 
the wing-tips.  Even though the vortex trail may not change in length or 
shape, it's appreance will change from frame to frame, so you'd need to 
switch between several identically shaped and sized objects that are textured 
slightly differently to give the impression of change.

If we could actually modify the model objects themselves then we could 'bend' 
the trails, and cut down on the number needed.

But then we could also do wing flexing too.

Before anyone starts thinking seriously about this, it would be very 
non-trivial to do, at least for the wings, where some objects would need to 
be 'bent' i.e. the wings and control surfaces, whereas other objects would 
have to simply translate i.e. wing mounted engine nacelles and U/C.

For a simple object, like a vortex trail, bending might be feasible, and 
combined with scaling (which I think we already have), it might work ok.

Another possiblity would be some sort of particle object handling where 
temporary objects could be generated, left for a while and then culled.  We 
could then 'drop' a stream of these objects behind the a/c that're culled 
after a certain time.  It'd probably need a lot of objects to work though, 
and it would also push up the object count of course.

Both methods would need some carefull texturing.

LeeE

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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


 Lee Elliott wrote
> 
> On Saturday 14 February 2004 18:35, Vivian Meazza wrote:
> > > Andy Ross
> > >
> > > Lee Elliott wrote:
> > > > I think drop tanks would be feasible but it would need some 
> > > > thinking
> > > > about:)
> > > >
> > > > The fun bit will be counteracting the a/c manuevours after the 
> > > > tank has dropped so it falls straight even though the a/c may be
> > >
> > > climbing
> > >
> > > > and banking.
> > >
> > > This is more of a code architecture issue.  Once 
> something has left 
> > > the aircraft, it ought be be handed to a simple 
> "ballistics FDM" or 
> > > somesuch.  Making it "disappear" from the aircraft model is as 
> > > simple as adding a select animation and can be done right 
> now.  And 
> > > you can set the weight tag to zero to get the FDM 
> behavior correct.
> > >
> > > Running it under a separate "FDM" handler is something 
> that the C++ 
> > > code just doesn't support yet, though.  It's probably not hugely 
> > > difficult to make work, though.
> > >
> > > Andy
> >
> > I was thinking in the short term to move the tank away from the 
> > aircraft in an arc, then select it, and set the fuel to 
> zero, and the 
> > empty weight to zero. Be nice to hand off to a separate FDM though.
> >
> > Vivian
> 
> While I think it might be feasible to drop a tank and have it 
> appear to drop 
> down from the a/c, and out of sight (and then quickly 
> de-selected), I think 
> trying to achieve any sort of realistic trajectory would be 
> pushing it a bit.
> 
> You've got to remember that the animation origins are 
> relative to the a/c so 
> after dropping something, you'd have to bare in mind that the 
> a/c, and 
> therefore the anim orign, are moving.  If the a/c turns after 
> dropping the 
> tank it would be very difficult to keep the tank moving in a 
> straight line 
> with the available anim controls.  The same thing applies to 
> climbs or 
> descents, but this would be less apparent from the a/c views. 
>  Would look a 
> bit odd from the tower though:)
> 
> LeeE
 
Of course we would like a parent/child FDM system, and from all these
postings is seems as if we nearly have. In the order of things, I don't
think it is very high on the todo list.

Vivian



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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


Jon Berndt wrote
 
> One feature in JSBSim that I began and have not yet finished 
> (pending other
> things) is a parent/child capability. You can (for instance) 
> load a Mk82 on an F-16 and the physical effects of the Mk82 
> will affect the F-16. The position is based on the position 
> of the parent, and so is the orientation. However, the Mk82 
> position is not integrated, it always has a position based on 
> the parent, UNTIL it is released. Then, the EOM begins 
> integrating and the flyout is physics based.
> 
> The child objects are each their own individual JSBSim 
> objects in their own right, and each could be loaded and 
> flown by itself. The JSBSim executive is sort of recursive in 
> this way. Each would be addressable in a way that I think 
> Tony set up with Properties, but I can't recall what it is.
> 
> Technically, it is also possible for each droppable piece to 
> have its own propulsion and flight control system, too. The 
> possiblities there are quite broad.
> 
> Unfortunately, my time is getting more limited by the day.
> 

Sounds VERY good. I'm sure you'll get round to it in due course.

Vivian



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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Jon Berndt
One feature in JSBSim that I began and have not yet finished (pending other
things) is a parent/child capability. You can (for instance) load a Mk82 on
an F-16 and the physical effects of the Mk82 will affect the F-16. The
position is based on the position of the parent, and so is the orientation.
However, the Mk82 position is not integrated, it always has a position based
on the parent, UNTIL it is released. Then, the EOM begins integrating and
the flyout is physics based.

The child objects are each their own individual JSBSim objects in their own
right, and each could be loaded and flown by itself. The JSBSim executive is
sort of recursive in this way. Each would be addressable in a way that I
think Tony set up with Properties, but I can't recall what it is.

Technically, it is also possible for each droppable piece to have its own
propulsion and flight control system, too. The possiblities there are quite
broad.

Unfortunately, my time is getting more limited by the day.

Jon


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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Saturday 14 February 2004 18:35, Vivian Meazza wrote:
> > Andy Ross
> >
> > Lee Elliott wrote:
> > > I think drop tanks would be feasible but it would need some thinking
> > > about:)
> > >
> > > The fun bit will be counteracting the a/c manuevours after the tank
> > > has dropped so it falls straight even though the a/c may be
> >
> > climbing
> >
> > > and banking.
> >
> > This is more of a code architecture issue.  Once something
> > has left the aircraft, it ought be be handed to a simple
> > "ballistics FDM" or somesuch.  Making it "disappear" from the
> > aircraft model is as simple as adding a select animation and
> > can be done right now.  And you can set the weight tag to
> > zero to get the FDM behavior correct.
> >
> > Running it under a separate "FDM" handler is something that
> > the C++ code just doesn't support yet, though.  It's probably
> > not hugely difficult to make work, though.
> >
> > Andy
>
> I was thinking in the short term to move the tank away from the aircraft in
> an arc, then select it, and set the fuel to zero, and the empty weight to
> zero. Be nice to hand off to a separate FDM though.
>
> Vivian

While I think it might be feasible to drop a tank and have it appear to drop 
down from the a/c, and out of sight (and then quickly de-selected), I think 
trying to achieve any sort of realistic trajectory would be pushing it a bit.

You've got to remember that the animation origins are relative to the a/c so 
after dropping something, you'd have to bare in mind that the a/c, and 
therefore the anim orign, are moving.  If the a/c turns after dropping the 
tank it would be very difficult to keep the tank moving in a straight line 
with the available anim controls.  The same thing applies to climbs or 
descents, but this would be less apparent from the a/c views.  Would look a 
bit odd from the tower though:)

LeeE



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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Saturday 14 February 2004 14:48, Jim Wilson wrote:
> Lee Elliott <[EMAIL PROTECTED]> said:
> > On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > > Any chance of modeling wingtip vortices (when CL is high enough above
> > > some threshhold) and rocket engine exhaust?
> > >
> > > :-)
> > >
> > > Jon
> >
> > If we could actually modify the model objects themselves then we could
> > 'bend' the trails, and cut down on the number needed.
>
> Plib supports a "tween" function that does exactly this.  It hasn't been
> added to fgfs animation support yet.  Basically if you have two vertices
> (or identical _sets_ of vertices) positioned at the two extremes of your
> range of motion, the tween function will move them all proportionately
> between according to a 0.0 to 1.0 ratio value.  Obviously you could bend or
> stretch or twist, or whatever you  wanted to.  This would be cool to have.
>
> Best,
>
> Jim

Bendy wings on the B-52 would be nice;)

LeeE


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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Saturday 14 February 2004 17:48, Andy Ross wrote:
> Lee Elliott wrote:
> > I think drop tanks would be feasible but it would need some thinking
> > about:)
> >
> > The fun bit will be counteracting the a/c manuevours after the tank
> > has dropped so it falls straight even though the a/c may be climbing
> > and banking.
>
> This is more of a code architecture issue.  Once something has left
> the aircraft, it ought be be handed to a simple "ballistics FDM" or
> somesuch.  Making it "disappear" from the aircraft model is as simple
> as adding a select animation and can be done right now.  And you can
> set the weight tag to zero to get the FDM behavior correct.
>
> Running it under a separate "FDM" handler is something that the C++
> code just doesn't support yet, though.  It's probably not hugely
> difficult to make work, though.
>
> Andy

Agreed, a simple 'ballastics' FDM would be a far better solution, but then 
someone's got to design & code it.

Not my field;)

LeeE


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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread David Culp
> This is more of a code architecture issue.  Once something has left
> the aircraft, it ought be be handed to a simple "ballistics FDM" or
> somesuch.  Making it "disappear" from the aircraft model is as simple
> as adding a select animation and can be done right now.  And you can
> set the weight tag to zero to get the FDM behavior correct.
>
> Running it under a separate "FDM" handler is something that the C++
> code just doesn't support yet, though.  It's probably not hugely
> difficult to make work, though.

A simple ballistics FDM already exists, located at 
src/AIModel/AIBallistic.cxx, and it works nicely on its own.  What is needed 
is for every FDM to have the ability to be a master or slave of any other 
FDM.  When in slave mode the slave FDM will get its [x,y,z,pitch,roll,bank] 
info from the master.  When released the slave will begin using its internal 
calculations.  It wouldn't be hard to add this to AIBase (the base class for 
AIBallistic, AIAircraft and AIShip).  Yasim and JSBSim could then have the 
master/slave ability added (JSBSim already has something like this, but it 
wasn't designed to work with all the other FDMs).

I think we just need to define the interface for every FDM, and the struct for 
passing the [x,y,z,pitch,roll,yaw] data.  If you want the slave FDM to effect 
the master, then it gets more complicated.  A simple FDM, like AIAircraft, 
can ignore the effects of the slave, but a complex FDM, like Yasim or JSBSim, 
would probably want to be effected by the slave.  For instance, if you make 
the JSBSim X-15 a slave to an AIAircraft B-52, then the B-52 can ignore the 
effects of the X-15.  If the X-15 is a slave to the Yasim B-52, then the B-52 
will probably want to figure in the effects of the X-15.

One thing that needs more work is in ensuring that the master and slave models 
get drawn at the same time.  I'm no graphics guy, so that's out of my league.  
I've noticed this is a problem when pulling up behind the AI KC-135 (or any 
AIAircraft object).  The AI object appears to leap forward in about 20-foot 
bursts.  It would look funny if the AIBallistic-based external fuel tank 
didn't follow the aircraft smoothly.  Curt had the idea of using a central 
graphics manager to manage the drawing of all objects, and that might do the 
trick.


Dave
-- 

David Culp
davidculp2[at]comcast.net


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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


> Andy Ross
 
> Lee Elliott wrote:
> > I think drop tanks would be feasible but it would need some thinking
> > about:)
> >
> > The fun bit will be counteracting the a/c manuevours after the tank 
> > has dropped so it falls straight even though the a/c may be 
> climbing 
> > and banking.
> 
> This is more of a code architecture issue.  Once something 
> has left the aircraft, it ought be be handed to a simple 
> "ballistics FDM" or somesuch.  Making it "disappear" from the 
> aircraft model is as simple as adding a select animation and 
> can be done right now.  And you can set the weight tag to 
> zero to get the FDM behavior correct.
> 
> Running it under a separate "FDM" handler is something that 
> the C++ code just doesn't support yet, though.  It's probably 
> not hugely difficult to make work, though.
> 
> Andy
> 

I was thinking in the short term to move the tank away from the aircraft in
an arc, then select it, and set the fuel to zero, and the empty weight to
zero. Be nice to hand off to a separate FDM though.

Vivian



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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Andy Ross
Lee Elliott wrote:
> I think drop tanks would be feasible but it would need some thinking
> about:)
>
> The fun bit will be counteracting the a/c manuevours after the tank
> has dropped so it falls straight even though the a/c may be climbing
> and banking.

This is more of a code architecture issue.  Once something has left
the aircraft, it ought be be handed to a simple "ballistics FDM" or
somesuch.  Making it "disappear" from the aircraft model is as simple
as adding a select animation and can be done right now.  And you can
set the weight tag to zero to get the FDM behavior correct.

Running it under a separate "FDM" handler is something that the C++
code just doesn't support yet, though.  It's probably not hugely
difficult to make work, though.

Andy

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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


 Norman Vine says
 
> Lee Elliott writes:
> > 
> > On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > > Any chance of modeling wingtip vortices (when CL is high enough 
> > > above some threshhold) and rocket engine exhaust?
> > 
> > 
> > Another possiblity would be some sort of particle object handling 
> > where
> > temporary objects could be generated, left for a while and 
> then culled.  We 
> > could then 'drop' a stream of these objects behind the a/c 
> that're culled 
> > after a certain time.  It'd probably need a lot of objects 
> to work though, 
> > and it would also push up the object count of course.
> 
> SSG supports 'particle systems' via the sgParticle class
> see PLIB / examples / src / ssg / dynamics / 
> 
> The easiest thing would probably be to write up a high level 
> interface to a new ParticleStream class < a time dependent 
> collection of sgParticles > 
> and then insert these into the scenegraph with a scriptable binding 
> 

I think my brain hurts. But if someone gives us the tools I'll do the
modelling. After I've done the Seahawk.

Vivian



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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Jim Wilson
Lee Elliott <[EMAIL PROTECTED]> said:

> On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > Any chance of modeling wingtip vortices (when CL is high enough above
> > some threshhold) and rocket engine exhaust?
> >
> > :-)
> >
> > Jon
>
> If we could actually modify the model objects themselves then we could 'bend' 
> the trails, and cut down on the number needed.
> 

Plib supports a "tween" function that does exactly this.  It hasn't been added
to fgfs animation support yet.  Basically if you have two vertices (or
identical _sets_ of vertices) positioned at the two extremes of your range of
motion, the tween function will move them all proportionately between
according to a 0.0 to 1.0 ratio value.  Obviously you could bend or stretch or
twist, or whatever you  wanted to.  This would be cool to have.

Best,

Jim


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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Saturday 14 February 2004 14:08, Norman Vine wrote:
> Lee Elliott writes:
> > On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > > Any chance of modeling wingtip vortices (when CL is high enough above
> > > some threshhold) and rocket engine exhaust?
> >
> > Another possiblity would be some sort of particle object handling where
> > temporary objects could be generated, left for a while and then culled. 
> > We could then 'drop' a stream of these objects behind the a/c that're
> > culled after a certain time.  It'd probably need a lot of objects to work
> > though, and it would also push up the object count of course.
>
> SSG supports 'particle systems' via the sgParticle class
> see PLIB / examples / src / ssg / dynamics /
>
> The easiest thing would probably be to write up a high level interface
> to a new ParticleStream class < a time dependent collection of sgParticles
> > and then insert these into the scenegraph with a scriptable binding
>
> Cheers
>
> Norman

A proper particle system would be a much better idea than trying to fake it 
with objects.

Something for the future perhaps.

LeeE


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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Norman Vine
Lee Elliott writes:
> 
> On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > Any chance of modeling wingtip vortices (when CL is high enough above
> > some threshhold) and rocket engine exhaust?
> 
> 
> Another possiblity would be some sort of particle object handling where 
> temporary objects could be generated, left for a while and then culled.  We 
> could then 'drop' a stream of these objects behind the a/c that're culled 
> after a certain time.  It'd probably need a lot of objects to work though, 
> and it would also push up the object count of course.

SSG supports 'particle systems' via the sgParticle class
see PLIB / examples / src / ssg / dynamics / 

The easiest thing would probably be to write up a high level interface
to a new ParticleStream class < a time dependent collection of sgParticles > 
and then insert these into the scenegraph with a scriptable binding 

Cheers

Norman

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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Saturday 14 February 2004 13:43, Vivian Meazza wrote:
> Lee Elliott wrote
>
> > On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > > Any chance of modeling wingtip vortices (when CL is high
> >
> > enough above
> >
> > > some threshhold) and rocket engine exhaust?
> > >
> > > :-)
> > >
> > > Jon
> >
> > I've thought about trying this but I think it could only be
> > really effective
> > in level flight.  As soon as you start banking the 'end' of
> > whatever trail
> > you're simulating will rotate (echos of the VRP issues:).
> >
> > For a very short trail this might not be noticable but for
> > longer ones I think
> > it's a bit of a show stopper.
> >
> > It would be possible to include curved trails in the model,
> > and the select
> > anim function could be used to select the appropriate model
> > object, but then
> > you'd need a wide range of trail objects.
> >
> > At first glance, this doesn't seem too bad, but then I think
> > you'd really need
> > several versions of each trail type so that you could switch
> > between them to
> > give the impression that the trail is changing throught time.
> >
> > Hmm...   I don't think I've explained that bit very well...
> >
> > Consider an a/c in stable level flight where votices are
> > being generated from
> > the wing-tips.  Even though the vortex trail may not change
> > in length or
> > shape, it's appreance will change from frame to frame, so
> > you'd need to
> > switch between several identically shaped and sized objects
> > that are textured
> > slightly differently to give the impression of change.
> >
> > If we could actually modify the model objects themselves then
> > we could 'bend'
> > the trails, and cut down on the number needed.
> >
> > But then we could also do wing flexing too.
> >
> > Before anyone starts thinking seriously about this, it would be very
> > non-trivial to do, at least for the wings, where some objects
> > would need to
> > be 'bent' i.e. the wings and control surfaces, whereas other
> > objects would
> > have to simply translate i.e. wing mounted engine nacelles and U/C.
> >
> > For a simple object, like a vortex trail, bending might be
> > feasible, and
> > combined with scaling (which I think we already have), it
> > might work ok.
> >
> > Another possiblity would be some sort of particle object
> > handling where
> > temporary objects could be generated, left for a while and
> > then culled.  We
> > could then 'drop' a stream of these objects behind the a/c
> > that're culled
> > after a certain time.  It'd probably need a lot of objects to
> > work though,
> > and it would also push up the object count of course.
> >
> > Both methods would need some carefull texturing.
>
> The second method could be very useful - drop tanks, ordinance, cockpit
> canopies, ejector seats, tyre smoke on landing. Not a high priority, I
> feel, but a nice to have. I want to do drop tanks on the hunter some time
> soon, but I can probably handle them well enough with the existing
> animations

I think drop tanks would be feasible but it would need some thinking about:)

The fun bit will be counteracting the a/c manuevours after the tank has 
dropped so it falls straight even though the a/c may be climbing and banking.

LeeE


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RE: [Flightgear-devel] Eye candy

2004-02-14 Thread Vivian Meazza


Lee Elliott wrote

> 
> 
> On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> > Any chance of modeling wingtip vortices (when CL is high 
> enough above 
> > some threshhold) and rocket engine exhaust?
> >
> > :-)
> >
> > Jon
> 
> I've thought about trying this but I think it could only be 
> really effective 
> in level flight.  As soon as you start banking the 'end' of 
> whatever trail 
> you're simulating will rotate (echos of the VRP issues:).
> 
> For a very short trail this might not be noticable but for 
> longer ones I think 
> it's a bit of a show stopper.
> 
> It would be possible to include curved trails in the model, 
> and the select 
> anim function could be used to select the appropriate model 
> object, but then 
> you'd need a wide range of trail objects.
> 
> At first glance, this doesn't seem too bad, but then I think 
> you'd really need 
> several versions of each trail type so that you could switch 
> between them to 
> give the impression that the trail is changing throught time.
> 
> Hmm...   I don't think I've explained that bit very well...
> 
> Consider an a/c in stable level flight where votices are 
> being generated from 
> the wing-tips.  Even though the vortex trail may not change 
> in length or 
> shape, it's appreance will change from frame to frame, so 
> you'd need to 
> switch between several identically shaped and sized objects 
> that are textured 
> slightly differently to give the impression of change.
> 
> If we could actually modify the model objects themselves then 
> we could 'bend' 
> the trails, and cut down on the number needed.
> 
> But then we could also do wing flexing too.
> 
> Before anyone starts thinking seriously about this, it would be very 
> non-trivial to do, at least for the wings, where some objects 
> would need to 
> be 'bent' i.e. the wings and control surfaces, whereas other 
> objects would 
> have to simply translate i.e. wing mounted engine nacelles and U/C.
> 
> For a simple object, like a vortex trail, bending might be 
> feasible, and 
> combined with scaling (which I think we already have), it 
> might work ok.
> 
> Another possiblity would be some sort of particle object 
> handling where 
> temporary objects could be generated, left for a while and 
> then culled.  We 
> could then 'drop' a stream of these objects behind the a/c 
> that're culled 
> after a certain time.  It'd probably need a lot of objects to 
> work though, 
> and it would also push up the object count of course.
> 
> Both methods would need some carefull texturing.
> 

The second method could be very useful - drop tanks, ordinance, cockpit
canopies, ejector seats, tyre smoke on landing. Not a high priority, I feel,
but a nice to have. I want to do drop tanks on the hunter some time soon,
but I can probably handle them well enough with the existing animations



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Re: [Flightgear-devel] Eye candy

2004-02-14 Thread Lee Elliott
On Friday 13 February 2004 22:27, Jon S Berndt wrote:
> Any chance of modeling wingtip vortices (when CL is high enough above
> some threshhold) and rocket engine exhaust?
>
> :-)
>
> Jon

I've thought about trying this but I think it could only be really effective 
in level flight.  As soon as you start banking the 'end' of whatever trail 
you're simulating will rotate (echos of the VRP issues:).

For a very short trail this might not be noticable but for longer ones I think 
it's a bit of a show stopper.

It would be possible to include curved trails in the model, and the select 
anim function could be used to select the appropriate model object, but then 
you'd need a wide range of trail objects.

At first glance, this doesn't seem too bad, but then I think you'd really need 
several versions of each trail type so that you could switch between them to 
give the impression that the trail is changing throught time.

Hmm...   I don't think I've explained that bit very well...

Consider an a/c in stable level flight where votices are being generated from 
the wing-tips.  Even though the vortex trail may not change in length or 
shape, it's appreance will change from frame to frame, so you'd need to 
switch between several identically shaped and sized objects that are textured 
slightly differently to give the impression of change.

If we could actually modify the model objects themselves then we could 'bend' 
the trails, and cut down on the number needed.

But then we could also do wing flexing too.

Before anyone starts thinking seriously about this, it would be very 
non-trivial to do, at least for the wings, where some objects would need to 
be 'bent' i.e. the wings and control surfaces, whereas other objects would 
have to simply translate i.e. wing mounted engine nacelles and U/C.

For a simple object, like a vortex trail, bending might be feasible, and 
combined with scaling (which I think we already have), it might work ok.

Another possiblity would be some sort of particle object handling where 
temporary objects could be generated, left for a while and then culled.  We 
could then 'drop' a stream of these objects behind the a/c that're culled 
after a certain time.  It'd probably need a lot of objects to work though, 
and it would also push up the object count of course.

Both methods would need some carefull texturing.

LeeE


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Re: [Flightgear-devel] Eye candy

2004-02-13 Thread Jon S Berndt
This would be nice:

http://www.dfrc.nasa.gov/Gallery/Photo/X-15/Small/EC68-1889.jpg

:-)

Jon

 Josh Babcock <[EMAIL PROTECTED]> wrote:
Actually, I'm pretty sure that with nasal and the animations we have 
we can do exhaust cones right now. Just model a cone, assign it a 
translucent, emmisive materiel and then use nasal to turn it on and 
off.  You can even make it get bigger and smaller with the 
animations.  Don't know how to do the smoke though.  Also, those 
little clouds that form over the wings at high lift would be cool 
too.

Josh

Jon S Berndt wrote:

Any chance of modeling wingtip vortices (when CL is high enough above 
some threshhold) and rocket engine exhaust?

:-)

Jon

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RE: [Flightgear-devel] Eye candy

2004-02-13 Thread Vivian Meazza


 Josh Babcock wrote
> 
> 
> Actually, I'm pretty sure that with nasal and the animations 
> we have we 
> can do exhaust cones right now. Just model a cone, assign it a 
> translucent, emmisive materiel and then use nasal to turn it on and 
> off.  You can even make it get bigger and smaller with the 
> animations.  
> Don't know how to do the smoke though.  Also, those little 
> clouds that 
> form over the wings at high lift would be cool too.
> 
> Josh
> 
> Jon S Berndt wrote:
> 
> > Any chance of modeling wingtip vortices (when CL is high 
> enough above
> > some threshhold) and rocket engine exhaust?
> >
 
The Hunter model has a rudimentary representation of gas turbine exhaust
using XML animation  I think smoke might be more difficult. Wingtip
vortices, and afterburner cones have been done on the T38. Condensation
clouds over wing surfaces would be fun: the conditions under which they form
might be difficult to calculate. Something I wanted to do in the future

Vivian Meazza



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Re: [Flightgear-devel] Eye candy

2004-02-13 Thread Josh Babcock
Actually, I'm pretty sure that with nasal and the animations we have we 
can do exhaust cones right now. Just model a cone, assign it a 
translucent, emmisive materiel and then use nasal to turn it on and 
off.  You can even make it get bigger and smaller with the animations.  
Don't know how to do the smoke though.  Also, those little clouds that 
form over the wings at high lift would be cool too.

Josh

Jon S Berndt wrote:

Any chance of modeling wingtip vortices (when CL is high enough above 
some threshhold) and rocket engine exhaust?

:-)

Jon

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Re: [Flightgear-devel] Eye Candy

2003-04-02 Thread Stefan Champailler
Now I want all the planes rendered with that !

stF

Norman Vine wrote:
If you have a machine to run this on :-)

http://www.daionet.gr.jp/~masa/rthdribl/index.html

Norman

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