Nice, but have you tried using a simple map constant in one direction and
containing a cross and two torii?  For the texture you could use the
object pattern, for an isosurface function this does not work of course.  

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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> Nice, but have you tried using a simple map constant in one direction and
> containing a cross and two torii?  For the texture you could use the
> object pattern, for an isosurface function this does not work of course.
>

Don't quite follow you there, Christoph.  What do you mean by a simple map
constant?

Thanks.

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This one any better?  I've tried to improve the texture and the lines are
thinner (thanks, Thomas).  As I've (i) never played basketball in my life
and (ii) only had to go off teeny weeny pictures from online sports stores
for reference, I think this is OK now.

The ZIP archive for the scene is in povray.binaries.scene-files.

Thanks for all your feedback, chaps!  Much appreciated. :O)

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Attachments:
Download 'basketball2.jpg' (63 KB)

Preview of image 'basketball2.jpg'

very nice, take another 10% or 20% off the dark lines.
a standard baseketball is a little bit more on the 'red' side, and I think
the surface is more rough (the bumps are much more noticable and kind of
roundish), the surface is also not as reflective
a more expensive leather basketball is more 'brown' and not as reflective,
the surface would work fine.

Thanks for the great explanation in you original mail !

cheers
Wolfgang

"Alan Holding" <man### [at] lineonenet> wrote in message
news:3b4d9acb@news.povray.org...
> This one any better?  I've tried to improve the texture and the lines are
> thinner (thanks, Thomas).  As I've (i) never played basketball in my life
> and (ii) only had to go off teeny weeny pictures from online sports stores
> for reference, I think this is OK now.
>
> The ZIP archive for the scene is in povray.binaries.scene-files.
>
> Thanks for all your feedback, chaps!  Much appreciated. :O)
>
>
>
>
>
>
>
>
>

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What a brilliant technique. It lends itself to many interesting applications.
Nice image.

DZ

Alan Holding wrote:

> Hello, all.
>
> This is a follow up to my post in povray.general.
>
> I'm doing a basketball based image at the moment, and decided to make the
> basketball using an isosurface.  However, coming up with a suitable
> image/bump map which could be spherically mapped onto the isosurface proved
> a real pain.  The maps I created in Paint Shop Pro never turned out right.
> So, after a think, I decided to create the image/bump map using MegaPOV's
> spherical camera - what better way to create a spherical map?
>
> Please see the attached pic for what I'm referring to in this bit.
>
> I had to imagine myself in the middle of a basketball (as you do).  What
> would cause the pattern that I'd see?  Well, two torii going around me
> should take care of the 'up and down' and 'left to right' lines, but the
> awkward squiggly bit would take more work...
>
> So, I created a patch model in Hamapatch (1) to simulate the squiggle.  This
> was simply two points which were spun with the lathe feature and then
> transformed and rotated about until I ended up with the final model.
>
> Next, I set up a scene in MegaPOV (2) with a spherical camera - the yellow
> dot - surrounded by the objects needed to create the map, the two torii and
> the Hamapatch model.  There was no lights in the scene and the textures used
> for the objects was black with an ambient of zero and no diffuse.  (The
> funky colours in (2) are just there to show what's what.)  Then I rendered
> the map (3), and finally placed it onto the isosurface basketball object as
> both an image map and a bump map in the isosurface's function (with a bit of
> noise3d thrown in).  The resulting object is shown in (4).
>
> What d'ya think?
>
> I'll post the image it's going in when it's completed.
>
> Bye,
> Alan.
>
> --
> ICQ 114025688
> Black & White?
>
>  [Image]

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Alan Holding wrote:
> 
> Don't quite follow you there, Christoph.  What do you mean by a simple map
> constant?

Just try an image map without special cylindrical mapping etc.  The used
image should contain a cross and two circles with the same radius as the
ball on one 'bar' of the cross each sqrt(2)*radius away from the center. 
Not tested BTW so i could be wrong.

You can also do the same with the object pattern and cylinders/boxes, but
for the isosurface this won't work.

Christoph

-- 
Christoph Hormann <chr### [at] gmxde>
IsoWood include, radiosity tutorial, TransSkin and other 
things on: http://www.schunter.etc.tu-bs.de/~chris/

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Maybe still a bit thick, but definitely better.  Too pinkish, more
brownish.

-- 
David Fontaine  <dav### [at] faricynet>  ICQ 55354965
My raytracing gallery:  http://davidf.faricy.net/

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Alan Holding wrote in message <3b4d11fb@news.povray.org>...
> I'm doing a basketball based image at the moment, and decided to make the
> basketball using an isosurface.

I don't want negate your very good "little tutorial" but when I looked at your
pictures I imagined that it should be possible with one pass - basket pigment
available via functions{}. Just look at my example (MegaPOV needed). If anybody
wants write it as macro with parameter as width of distance beetween "circles"
on the ball - just do it and upload it somewhere on this server - unfortunatly I
have no time.

#declare A=30; // angle - from 0 to 90
#declare C=vrotate(z,y*A);// center of "circle" in 1/8 part
#declare Cx=C.x;#declare Cy=C.y;#declare Cz=C.z;
#declare M=vrotate(z,-x*45);// middle between centers of two "circles"
#declare RA=vdot(C,M);// radius of circle for ball's radius=1

#declare R=function{"R"}
#declare VDot=function{Cx*x+Cy*y+Cz*z}
#declare Basket8=function{if(VDot(x,y,z)-RA,0,1)}
#declare Basket4=function{if(y,Basket8(x,y,z),Basket8(x,-y,z))}
#declare Basket2=function{if(z,Basket4(x,y,z),Basket4(x,y,-z))}
#declare Basket1=function{if(x,Basket2(x,y,z),1-Basket2(-x,z,y))}
sphere{0 1 pigment{function{Basket1}}}

--
#macro Sig(A,B,X)_(A,B)_(B,X)_(X,A)#end#macro _(A,B)cylinder{<A.x,A.y,3>,<B.u,
B.v,3>.1,9}#end global_settings{max_trace_level 9}light_source{0 1}camera{up y
*4right-3*x}blob{_(<3,1>,<1,-5>)_(<2,-2>,<4,-2>)Sig(x,<-1,1.5>,<1,3>)_(z-1,z-4
)pigment{rgb 1}}box{-3 3pigment{rgb 0}finish{reflection 1}hollow} // POV-Ray31

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Attachments:
Download 'ball.jpg' (19 KB)

Preview of image 'ball.jpg'

Ooo. Nice... source please?
"Alan Holding" <man### [at] lineonenet> wrote in message
news:3b4d9acb@news.povray.org...
> This one any better?  I've tried to improve the texture and the lines are
> thinner (thanks, Thomas).  As I've (i) never played basketball in my life
> and (ii) only had to go off teeny weeny pictures from online sports stores
> for reference, I think this is OK now.
>
> The ZIP archive for the scene is in povray.binaries.scene-files.
>
> Thanks for all your feedback, chaps!  Much appreciated. :O)
>
>
>
>
>
>
>
>
>

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"Mahalis" <don### [at] fakeycom> wrote in message
news:3ba60b53$1@news.povray.org...
> Ooo. Nice... source please?

It's now part of the POV-Ray Objects Collection managed by Micha Riser.

http://www.povworld.de/objects/

Look under Object Categories/Isosurface.  The syntax is for MegaPOV, so you
will need to tweak it if you want it to work with POV-Ray 3.5

--

www.mp3.com/FeedingTheCats
www.btinternet.com/~manhog/

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