POV-Ray : Newsgroups : povray.binaries.animations : Grass Wind Test 2 (mpg 480kbu) Server Time
19 Jul 2024 17:25:18 EDT (-0400)
  Grass Wind Test 2 (mpg 480kbu) (Message 1 to 10 of 14)  
Goto Latest 10 Messages Next 4 Messages >>>
From: Rune
Subject: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 13:45:10
Message: <3ca4b636@news.povray.org>
I tried to follow some of your suggestions, and this is the result. I think
it's better, but I can still use some more suggestions for improvement. :)

Rune
--
3D images and anims, include files, tutorials and more:
Rune's World:  http://rsj.mobilixnet.dk (updated Feb 16)
POV-Ray Users: http://rsj.mobilixnet.dk/povrayusers/
POV-Ray Ring:  http://webring.povray.co.uk


Post a reply to this message


Attachments:
Download 'fgrass2_test4.mpg' (481 KB)

From:
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 13:49:39
Message: <4ld9auc2nut4lhlm81r53egldoqpokhoim@4ax.com>
On Fri, 29 Mar 2002 19:41:48 +0100, "Rune" <run### [at] mobilixnetdk> wrote:
> I tried to follow some of your suggestions, and this is the result. I think
> it's better, but I can still use some more suggestions for improvement. :)

I don't know how to describe such feeling in english but it is something like
elastic ground. Probably not helpfull comment :-( I wait how your macro evolve
becouse I have ready usage for it in my current scene.

ABX


Post a reply to this message

From: Rick [Kitty5]
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 18:37:55
Message: <3ca4fad3$1@news.povray.org>
> I don't know how to describe such feeling in english but it is something
like
> elastic ground. Probably not helpfull comment :-( I wait how your macro
evolve
> becouse I have ready usage for it in my current scene.

yeah, it looks better, but does appear to 'bounce'


--
Rick

Kitty5 WebDesign - http://Kitty5.com
POV-Ray News & Resources - http://Povray.co.uk
TEL : +44 (01270) 501101 - FAX : +44 (01270) 251105 - ICQ : 15776037

PGP Public Key
http://pgpkeys.mit.edu:11371/pks/lookup?op=get&search=0x231E1CEA


Post a reply to this message

From: Marc van den Dikkenberg
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 18:42:24
Message: <wvqkPHADiHCjwoZDeQ8Q17V8UcBQ@4ax.com>
On Fri, 29 Mar 2002 19:41:48 +0100, "Rune" <run### [at] mobilixnetdk>
wrote:

>I tried to follow some of your suggestions, and this is the result. I think
>it's better, but I can still use some more suggestions for improvement. :)

It does seem a bit rubbery, but I am not sure how much the circular
camerapath is adding to that... You may want to make a demo of the wind
with a stationary camera, maybe that will diminish the motion-sickness
factor a little. :-)

-- 
Marc van den Dikkenberg
--
The PowerBasic Archives -- http://www.xlsior.org


Post a reply to this message

From: Bill DeWitt
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 19:16:46
Message: <3ca503ee@news.povray.org>
"Rune" <run### [at] mobilixnetdk> wrote :
>
> I tried to follow some of your suggestions, and this is the result. I
think
> it's better, but I can still use some more suggestions for improvement. :)

    I actually watched some grass this afternoon, and my grass doesn't bend
in the middle unless it is a typhoon. It bends along it's whole length
somewhat. And in the size range of what you have, only one gust would fit on
the screen at the time.


Post a reply to this message

From: Rune
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 20:16:57
Message: <3ca51209@news.povray.org>
"Bill DeWitt" wrote:
>     I actually watched some grass this afternoon,
> and my grass doesn't bend in the middle unless it
> is a typhoon. It bends along it's whole length
> somewhat.

My simulated grass also bends along its whole length. Actually, it's just a
simple parabolic function. (In the last animation it was linear.) One side
effect of the method used is that the blades get longer the more they bend,
but that's just one of the compromises of this simulated grass...

> And in the size range of what you have, only one
> gust would fit on the screen at the time.

Hmm, ok. But won't it looks wrong if all the blades bend in the same way at
the same time? Maybe not...

Rune
--
3D images and anims, include files, tutorials and more:
Rune's World:  http://rsj.mobilixnet.dk (updated Feb 16)
POV-Ray Users: http://rsj.mobilixnet.dk/povrayusers/
POV-Ray Ring:  http://webring.povray.co.uk


Post a reply to this message

From: Sir Charles W  Shults III
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 21:20:50
Message: <3ca52102$1@news.povray.org>
I did a little observation of my yard today and I found out some interesting
things about grass movement.
    First, only the longer blades bend very much, and when they do, it is really
a complex sort of movement.
    Second, the movement has two distinct components- bending and oscillating.
When the wind blows over longer stalks or leaves, they tend to bend gently over
the length, pretty much as the parabolic bending in your model.  It may actually
be a catenary curve due to the forces and loading, but that is a small thing.
    But the oscillating movement is a side to side twisting, more rapid for
shorter blades than for longer ones.  The oscillation period is much shorter
than the bending or waving period.  The wind moves in "swells" over large,
curved or crescent shaped areas, exciting the stiffer stalks to oscillate more
and the thinner or longer ones to bend and curve.
    This is way too much complexity I think for the model you have.  The texture
itself looks great as it stand; getting realistic looking movement may be far
harder than it is worth right now.
    If I were modelling grass and leaves in the wind, I would attach masses or
springiness to control points and apply forces against them.  Otherwise, the
movement tends to look more like seaweed drifting in the water, which is
essentially what your texture may naturally tend to emulate.  Don't give up; it
already makes nice turtle grass for undersea animations!

Cheers!

Chip Shults
My robotics, space and CGI web page - http://home.cfl.rr.com/aichip


Post a reply to this message

From: Bill DeWitt
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 29 Mar 2002 23:53:53
Message: <3ca544e1@news.povray.org>
"Rune" <run### [at] mobilixnetdk> wrote in message
news:3ca51209@news.povray.org...
> "Bill DeWitt" wrote:
> >     I actually watched some grass this afternoon,
> > and my grass doesn't bend in the middle unless it
> > is a typhoon. It bends along it's whole length
> > somewhat.
>
> My simulated grass also bends along its whole length. Actually, it's just
a
> simple parabolic function. (In the last animation it was linear.) One side
> effect of the method used is that the blades get longer the more they
bend,
> but that's just one of the compromises of this simulated grass...

    Maybe that's it. It looked a little springy to me. And I think it really
bends too much, it almost looks like seagrass.

> > And in the size range of what you have, only one
> > gust would fit on the screen at the time.
>
> Hmm, ok. But won't it looks wrong if all the blades bend in the same way
at
> the same time? Maybe not...

    No, the gust would sweep across the view, and when one was partly off,
another would be partly on.


Post a reply to this message

From: Artis
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 30 Mar 2002 04:12:47
Message: <3CA57E29.2060308@aaa.apollo.lv>
> I tried to follow some of your suggestions, and this is the result. I think
> it's better, but I can still use some more suggestions for improvement. :)

Cool, dancing grass!!!


Post a reply to this message

From: Rune
Subject: Re: Grass Wind Test 2 (mpg 480kbu)
Date: 30 Mar 2002 04:57:47
Message: <3ca58c1b$1@news.povray.org>
Thanks for all the suggestions everyone, but I think I'll just drop adding
support for wind.

Rune
--
3D images and anims, include files, tutorials and more:
Rune's World:  http://rsj.mobilixnet.dk (updated Feb 16)
POV-Ray Users: http://rsj.mobilixnet.dk/povrayusers/
POV-Ray Ring:  http://webring.povray.co.uk


Post a reply to this message

Goto Latest 10 Messages Next 4 Messages >>>

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.