I posted a picture in images of a bowl of leftover snack mix. It's still a
WIP, but I'm having fun. The original concept was to FILL the bowl with a
"home-tossed" snack mix. However, I ended up placing each "item" by hand
becuase I could not find anything in POV that would allow "dropping" items
into a bowl with collision decisions. I'm still a POV purist at this point
and don't know many add-ins or third party software. I assume there is
something that will allow me to fill this bowl realistically. Is that true?

--
-Flu

"Imagination is the foundation of Reality" - Gallagher

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Flu <wflu at att dot net> wrote in message news:3e87b122@news.povray.org...
> I posted a picture in images of a bowl of leftover snack mix. It's still a
> WIP, but I'm having fun. The original concept was to FILL the bowl with a
> "home-tossed" snack mix. However, I ended up placing each "item" by hand
> becuase I could not find anything in POV that would allow "dropping" items
> into a bowl with collision decisions. I'm still a POV purist at this point
> and don't know many add-ins or third party software. I assume there is
> something that will allow me to fill this bowl realistically. Is that
true?
>
> --
> -Flu
>
> "Imagination is the foundation of Reality" - Gallagher
>
>

assuming you are using 3.5, you should look into using trace(). i always
heard so much about it but never actually tried using it until last night.
It works nicely for finding the place where a vector intersects an object.
then you can use the returned vector to translate your object.


ross.

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Ross Litscher wrote:

> assuming you are using 3.5, you should look into using trace(). i always
> heard so much about it but never actually tried using it until last night.
> It works nicely for finding the place where a vector intersects an object.
> then you can use the returned vector to translate your object.

That's good for positioning against a single target object but how do you
test against multiple objects as each one is is postioned into the container,
especially considering that each object is shaped differently?

-- 
Ken Tyler

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Wasn't it Flu who wrote:
>I posted a picture in images of a bowl of leftover snack mix. It's still a
>WIP, but I'm having fun. The original concept was to FILL the bowl with a
>"home-tossed" snack mix. However, I ended up placing each "item" by hand
>becuase I could not find anything in POV that would allow "dropping" items
>into a bowl with collision decisions. I'm still a POV purist at this point
>and don't know many add-ins or third party software. I assume there is
>something that will allow me to fill this bowl realistically. Is that true?

It might be worth looking at the code in the example scenes
advanced\blocks folder.

-- 
Mike Williams
Gentleman of Leisure

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I'm not sure how much that would be against the
purist's convention, but Christoph Hormann's
Mechsim-Patch might be useful for that. He
began with using functions and calculating everything
via POV SDL, but then referred to patching, because
SDL is waaaaay slower than an actual program.
So its not totally vs the POV purist concept if
you use his patch...

--
Tim Nikias v2.0
Homepage: http://www.digitaltwilight.de/no_lights
Email: Tim### [at] gmxde

> I posted a picture in images of a bowl of leftover snack mix. It's still a
> WIP, but I'm having fun. The original concept was to FILL the bowl with a
> "home-tossed" snack mix. However, I ended up placing each "item" by hand
> becuase I could not find anything in POV that would allow "dropping" items
> into a bowl with collision decisions. I'm still a POV purist at this point
> and don't know many add-ins or third party software. I assume there is
> something that will allow me to fill this bowl realistically. Is that
true?
>
> --
> -Flu
>
> "Imagination is the foundation of Reality" - Gallagher
>
>

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Collision detection of a free object (ie freely shaped) with another free
object is an extremely difficult problem. Using trace() won't help you
much; it only helps if you want to place a *point* on the surface of an
object, not if you want to place an *object* (specially if the shapd of the
object in question is complicated).

  And collision detection alone is not enough. Even if you had a perfect
collision detection mechanism, that won't give you what you want. The objects
will simply collide with the other objects, and then stay in that position,
whichever it is. Which is of course unnatural.
  Besides collision detection you would also need a physics modelling
mechanism to calculate how the object would fall, collide, change orientation
etc until it ends up in a state of balance.

  An extremely complicated task.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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Hm. Maybe you could even do that without Mechsim:

A very simple approach would be to create simply hulls
for your objects. Like a 2D-hexagon-polygon for the
smarties. Then, you shoot one trace onto the bowl.
Place the polygon there, plus some height to keep adjusted
that the hull is 2D, but the object you want to place is 3D.

Then, shoot another trace through one of the corners of the
polygon. Rotate the polygon to match the corner with the
traced corner.
Redo this several times, cause a rotated corner has a slightly
different position than the intersection of a straight ray traced
onto the surface. Also do this for the other corners, but
try not to move the center of the object/polygon somewhere
else.
In this manner, you place an object, and rotate its orientation to
meet the underlying structure.

Then, add the newly placed object into a union with the bowl,
and add the next object. This one is again placed into the
union, and the trace is always applied on the latest union.
This might need some Input-Output of objects, and isn't
a very easy task to script. But it could be useful for later
projects as well, and thus might be worth the effort.

--
Tim Nikias v2.0
Homepage: http://www.digitaltwilight.de/no_lights
Email: Tim### [at] gmxde

> I'm not sure how much that would be against the
> purist's convention, but Christoph Hormann's
> Mechsim-Patch might be useful for that. He
> began with using functions and calculating everything
> via POV SDL, but then referred to patching, because
> SDL is waaaaay slower than an actual program.
> So its not totally vs the POV purist concept if
> you use his patch...
>
> --
> Tim Nikias v2.0
> Homepage: http://www.digitaltwilight.de/no_lights
> Email: Tim### [at] gmxde
>
> > I posted a picture in images of a bowl of leftover snack mix. It's still
a
> > WIP, but I'm having fun. The original concept was to FILL the bowl with
a
> > "home-tossed" snack mix. However, I ended up placing each "item" by hand
> > becuase I could not find anything in POV that would allow "dropping"
items
> > into a bowl with collision decisions. I'm still a POV purist at this
point
> > and don't know many add-ins or third party software. I assume there is
> > something that will allow me to fill this bowl realistically. Is that
> true?
> >
> > --
> > -Flu
> >
> > "Imagination is the foundation of Reality" - Gallagher
> >
> >
>
>

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Just to clarify, I am a "purist" at the moment for the fact that POV is all
that I have played with. It was not my intention to find a way to do this
and STAY a purist. I want to learn other apps, but I am just playing with
POV at the moment. I fully expected that an "outside" program would be
needed to do this, I just didn't know where to begin looking.

Thanks, Flu



"Tim Nikias v2.0" <tim### [at] gmxde> wrote in message
news:3e87fac6@news.povray.org...
> I'm not sure how much that would be against the
> purist's convention, but Christoph Hormann's
> Mechsim-Patch might be useful for that. He
> began with using functions and calculating everything
> via POV SDL, but then referred to patching, because
> SDL is waaaaay slower than an actual program.
> So its not totally vs the POV purist concept if
> you use his patch...
>
> --
> Tim Nikias v2.0
> Homepage: http://www.digitaltwilight.de/no_lights
> Email: Tim### [at] gmxde
>
> > I posted a picture in images of a bowl of leftover snack mix. It's still
a
> > WIP, but I'm having fun. The original concept was to FILL the bowl with
a
> > "home-tossed" snack mix. However, I ended up placing each "item" by hand
> > becuase I could not find anything in POV that would allow "dropping"
items
> > into a bowl with collision decisions. I'm still a POV purist at this
point
> > and don't know many add-ins or third party software. I assume there is
> > something that will allow me to fill this bowl realistically. Is that
> true?
> >
> > --
> > -Flu
> >
> > "Imagination is the foundation of Reality" - Gallagher
> >
> >
>
>

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Oh. Okay. I'm the sort of purist you seem not willing
to be. :-)

(Patience is a major requirement for being that sort
of Purist...:-)

--
Tim Nikias v2.0
Homepage: http://www.digitaltwilight.de/no_lights
Email: Tim### [at] gmxde

> Just to clarify, I am a "purist" at the moment for the fact that POV is
all
> that I have played with. It was not my intention to find a way to do this
> and STAY a purist. I want to learn other apps, but I am just playing with
> POV at the moment. I fully expected that an "outside" program would be
> needed to do this, I just didn't know where to begin looking.
>
> Thanks, Flu
>
>
>

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In article <3e882bd6@news.povray.org>, war### [at] tagpovrayorg says...
>   Collision detection of a free object (ie freely shaped) with another free
> object is an extremely difficult problem. Using trace() won't help you
> much; it only helps if you want to place a *point* on the surface of an
> object, not if you want to place an *object* (specially if the shapd of the
> object in question is complicated).
> 
>   And collision detection alone is not enough. Even if you had a perfect
> collision detection mechanism, that won't give you what you want. The objects
> will simply collide with the other objects, and then stay in that position,
> whichever it is. Which is of course unnatural.
>   Besides collision detection you would also need a physics modelling
> mechanism to calculate how the object would fall, collide, change orientation
> etc until it ends up in a state of balance.
> 
>   An extremely complicated task.
> 
> 
I haven't looked to deep into it, but.. Does Truespace have the capacity 
to export the position and orientation of object in a scene at some 
arbitrary point in an animation? If so, then the free version 3.0 that is 
floating around could be used to allow approximations of the objects, or 
even real Truespace copies of them, to 'fall' into the destination object 
and export the final position of all the objects in the last frame of the 
animation. A tool of some sort that was designed to do such an 
approximation to generate POVRay 'frames' would be a really nice thing to 
see someone build some day if you can't use Truespace to cheat such 
frames into existence. Right now, this is one of the major inconveniences 
that exists for trying to do realistic stuff in POV.


-- 
void main () {

    call functional_code()
  else
    call crash_windows();
}

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