Hi,

As I read through the POV-Documentation about the Poly-Object
I came across the following : 'Polys are, however, seldom used
in scenes due to the fact that they are so difficult to define
and it's far from trivial to get the desired shape with just a
polynomial equation.' So I thought something has to be done to
make it usable again, because it's so versatile and useful if
it does what you want from it :)
Long babbling... now to the Point: I've wrote a Program which
tries to find good poly-parameters to get the desired object.
At First one has to set the Order of the Object.
Then the User has to specify points in 3D (other dimensions are
supported, too ) and their respective function-value. The User
can also weight the different points differently. After that
the program tries to find better and better solutions. If it
finds a better solution it outputs a poly-object and an equal
function (which can be used in isosurfaces e.g.) into a txt-file.

Since I've just finished the program i couldn't play with it much
so this is just an example. If someone is interested i'll explain
more.

Greetings
Thies

P.S.: The Images show a 3rd Order Poly which goes through 11 little
spheres on a big sphere and the center of the sphere.

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Attachments:
Download 'polyopt1.jpg' (24 KB) Download 'polyopt2.jpg' (25 KB) Download 'polyopt3.jpg' (24 KB)

Preview of image 'polyopt1.jpg'

Preview of image 'polyopt2.jpg'

Preview of image 'polyopt3.jpg'

Can it do spheres too?

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"Apache" <apa### [at] yahoocom> wrote in
news:3d3c9697$1@news.povray.org...
> Can it do spheres too?
Yes, it can do spheres, too. In fact, spheres are in
most cases relatively easily computed. Usually you
specify some points on the surface of the sphere and
give them the function-value 0.0 and one (or more)
points inside of the sphere with a negative function-
value to make sure the function isn't completely 0
Then you let the prog find a fitting 2nd Order Poly.
This works in most cases.

Greetings
Thies

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Is it a stand alone or POV program?
About how long does it take?

Got a copy?


--
Have Fun!

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Hi,

"Leroy Whetstone" <lrw### [at] joplincom>
wrote in news:3D3E4E77.E55DBAB7@joplin.com...

> Is it a stand alone or POV program?
It's a stand-alone program because of Speed
and it would have been rather hard for me
to implement it in POV-SDL.

> About how long does it take?
That depends on how complex the object is
that you specify and the Order of the
Poly/Function. If you just want to have an
ellipsoid that goes smoothly through e.g.
6 Points and there is a possible solution
it would probably take about a minute.
But if you want a complex edgy 10th order
object you can easily wait a few days i
think :)
it really depends. The easier the shape
the shorter the calculation-time.

> Got a copy?
Sure, i will be happy to share it. The only
problem is that i haven't implemented a
input-file parser to specify the parameters.
Currently i hardcode the Points into the
Program and recompile it. But i'll try to
implement a parser in the next days.

So at the moment i can just offer the source-
code for you.

Greetings,
Thies

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