As luck would have it, the flocking concept I was already working on may
prove a nice fit with the IRTC topic of Alien Invasion.

I tried all kinds of exotic algorithms. Nothing looked better than a
simple repulsion from the surface at several points ahead along the
current velocity of the particle.

http://members.xoom.com/_XMCM/gregjohn/animation.html#POV13

Made with the MegaPOV patch of     "POV-Ray-- A Raytracer, Not a
Modeller"

Post a reply to this message

Attachments:
Download 'flyby16b.jpg' (15 KB)

Preview of image 'flyby16b.jpg'

It's interesting that the objects even change their rotation when following
the contours of the ground. This is going to be a great IRTC entry!

-Dave

"Greg M. Johnson" <"gregj;-)56590\""@aol.c;-)om> wrote in message
news:397b3bd7@news.povray.org...
> I tried all kinds of exotic algorithms. Nothing looked better than a
> simple repulsion from the surface at several points ahead along the
> current velocity of the particle.

Post a reply to this message

"Greg M. Johnson" wrote:
> As luck would have it, the flocking concept I was already
> working on may prove a nice fit with the IRTC topic of
> Alien Invasion.
>
> I tried all kinds of exotic algorithms. Nothing looked better than a
> simple repulsion from the surface at several points ahead along the
> current velocity of the particle.

Very nice!

I think it might look better with some more motion though. They might look
more alive and more alien if they flew in and out amongst each other.

A suggestion: Make each boid attracted to both boid N+1 AND boid N-1. And
make the attraction very weak. That way you would probably get a more
"alive" formation, but still avoid a visible chain formation.

Greetings,

Rune
--
Updated July 23: http://rsj.mobilixnet.dk
3D images, include files, stereograms, tutorials,
The POV Desktop Theme, The POV-Ray Logo Contest,
music, 350+ raytracing jokes, and much more!

Post a reply to this message

Thanks, yes, they are a bit tidy.   I think I would change my "actave," or
attractive point, to be different for each and to travel with a z component
that changes as a function of time. something like,

#declare actave=<-460+time*constant,100, 10*sin(2*pi*(time/totaltime*4 +
particlenumber/#particles) >;

Rune wrote:

> "Greg M. Johnson" wrote:
> > As luck would have it, the flocking concept I was already
> > working on may prove a nice fit with the IRTC topic of
> > Alien Invasion.
> >
> > I tried all kinds of exotic algorithms. Nothing looked better than a
> > simple repulsion from the surface at several points ahead along the
> > current velocity of the particle.
>
> Very nice!
>
> I think it might look better with some more motion though. They might look
> more alive and more alien if they flew in and out amongst each other.
>
> A suggestion: Make each boid attracted to both boid N+1 AND boid N-1. And
> make the attraction very weak. That way you would probably get a more
> "alive" formation, but still avoid a visible chain formation.
>
> Greetings,
>
> Rune
> --
> Updated July 23: http://rsj.mobilixnet.dk
> 3D images, include files, stereograms, tutorials,
> The POV Desktop Theme, The POV-Ray Logo Contest,
> music, 350+ raytracing jokes, and much more!

Post a reply to this message

Wow...cool...awesome, dude!

"Greg M. Johnson" wrote:
> 
> As luck would have it, the flocking concept I was already working on may
> prove a nice fit with the IRTC topic of Alien Invasion.
> 
> I tried all kinds of exotic algorithms. Nothing looked better than a
> simple repulsion from the surface at several points ahead along the
> current velocity of the particle.
> 
> http://members.xoom.com/_XMCM/gregjohn/animation.html#POV13
> 
> Made with the MegaPOV patch of     "POV-Ray-- A Raytracer, Not a
> Modeller"
> 
>   ------------------------------------------------------------------------
>  [Image]

Post a reply to this message

"Greg M. Johnson" wrote:
> Thanks, yes, they are a bit tidy. I think I would change my "actave,"
> or attractive point, to be different for each and to travel with a z
> component that changes as a function of time. something like,
>
> #declare actave=<-460+time*constant,100, 10*sin(2*pi*(time/totaltime*4
> + particlenumber/#particles) >;

Ah, interesting. However, I would think that it would cause the boids to be
very tidy when the attractive point is very far away, and very untidy when
the attractive point is very close. Not an optimal solution, in my opinion.

I'm working on a boid system of my own (just started today), and I'm working
on similar problems right now. Among other things I found out that making
boid N attracted to boid N+1 and N-1 (as I suggested to you) assembles a
rather static chain. Not very smart! N+1 and N+1+number_of_boids/2 gives a
moebius chain! Interesting, but not very useful. I'm trying to find a way
that makes them look untidy in a random and natural way. I think I'm pretty
close now.

Look forward to see more of your work!

Greetings,

Rune
--
Updated July 23: http://rsj.mobilixnet.dk
3D images, include files, stereograms, tutorials,
The POV Desktop Theme, The POV-Ray Logo Contest,
music, 350+ raytracing jokes, and much more!

Post a reply to this message

I'm getting close by having the actors each attracted to a UNIQUE attraction
point, and having this attraction point move back in forth in z as the group
travels in x.   I haven't yet found a middle ground value that looks cool (low:
no effect, high: boring chaos).

Rune wrote:

> Ah, interesting. However, I would think that it would cause the boids to be
> very tidy when the attractive point is very far away, and very untidy when
> the attractive point is very close. Not an optimal solution, in my opinion.

Post a reply to this message

In article <397e3c2a@news.povray.org>, "Rune" <run### [at] inamecom> 
wrote:

> I'm working on a boid system of my own (just started today), and I'm 
> working on similar problems right now. Among other things I found out 
> that making boid N attracted to boid N+1 and N-1 (as I suggested to 
> you) assembles a rather static chain. Not very smart! N+1 and 
> N+1+number_of_boids/2 gives a moebius chain! Interesting, but not 
> very useful. I'm trying to find a way that makes them look untidy in 
> a random and natural way. I think I'm pretty close now.

Maybe have all of them try for a certain preferred height, different for 
each one, and only vary from this height in order to avoid others and 
the landscape. Also, maybe make them try to reach the "center" of the 
flock(the average of their positions?), yet be repelled from others.

This is interesting, and somewhat similar to particle and cloth 
simulation...maybe I will try my hand at it. Maybe give some more 
"intelligence" to each boid, and have them behave differently in 
different situations. Maybe even get them to play "king of the hill" or 
tag.

-- 
Christopher James Huff - Personal e-mail: chr### [at] maccom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://homepage.mac.com/chrishuff/
TAG Web page: http://tag.povray.org/

Post a reply to this message

Chris Huff wrote:

> This is interesting, and somewhat similar to particle and cloth
> simulation...maybe I will try my hand at it. Maybe give some more
> "intelligence" to each boid, and have them behave differently in
> different situations. Maybe even get them to play "king of the hill" or
> tag.

If my tutorial is not too sophomoric for an expert such as yourself,
consider:

http://www.geocities.com/pterandon/boids.html

Post a reply to this message

In article <397f86a9@news.povray.org>, "Greg M. Johnson" 
<"gregj;-)56590\""@aol.c;-)om> wrote:

> If my tutorial is not too sophomoric for an expert such as yourself,
> consider:
> 
> http://www.geocities.com/pterandon/boids.html

I'm definitely not an expert, I haven't even done one simulation like 
this.
BTW, the description of the boid behavior on your page comes very close 
to the inter-particle force calculation of my particle system...

-- 
Christopher James Huff - Personal e-mail: chr### [at] maccom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://homepage.mac.com/chrishuff/
TAG Web page: http://tag.povray.org/

Post a reply to this message