Well, it turns out the iso surface 'water' works pretty well, but when it's
scaled up to be the surface of my aquarium, the spherical portion makes the
middle look 'lower'.  I could probably fix this, but it's SLOW.

I've basically abandon'd my Isosurface at this point - a procedural
heighfield and Instersection seems to be working much better.  Will post
results later.

       == John ==

"Bob H." <omn### [at] msncom> wrote in message
news:3b4a0bb8@news.povray.org...
> "John D. Gwinner" <jgw### [at] hotmailcom> wrote in message
> news:3b49b802$1@news.povray.org...
> > Ah, thanks - I'd been playing with the functions to see what the effect
> was
> > so that's probably where the x,z,y came from.
> >
> > I didn't think it was a bug exactly, I thought I was doing something
wrong
> >
> > How would we isolate the bug?
>
> Well, being the mere end-user that I am there's not much to try except
make
> sure the surface level changes along the y axis as a whole instead of just
> the pattern changes one would expect.
> I put a semitransparent y plane across the isosurface and placed the
camera
> nearly parallel with it to see if the surface really does rise and fall as
a
> whole.  It did.  The amount of shift is small but I believe what is
> happening is that the function is somehow changing the color_map or isn't
> remaining stable.
> That is to say, perhaps it brightens and darkens overall instead of only
> shifting the color values around in a prespecified range.  If you look at
> the patterns themselves you will see the patterns like ripples or bozo
(bozo
> is especially obvious once animated) transform rgb 0 to rgb 1 while rgb 1
> goes to rgb 0 along the pattern wave type.
> We can only see the isosurface undulating though to prove or disprove
> anything, since the patterns themselves as pigments look correct.
> Try the script below if you like, I'm not absolutely certain wrinkles is
the
> only problemed pattern, granite looks awful when phased.  As Mike Williams
> has said it could be all in how the pattern equations are done, something
I
> know nothing about.  But it looks as though all are subjected to the same
> undulation of the isosurface and there isn't anything there I can figure
to
> cause it aside from phase.
>
> Bob H.
>
> > I was wrong about the news link, it's
> > news:news.povray.org/povray.binaries.animations, "Rot and Renewal".  And
> now
> > that I check it, I had the x,z,y *lol*.  Back to the IDE ..
>
> #version unofficial MegaPov 0.7;
>
> #declare R=1.0;
> #declare R1=R+0.01;
> #declare Box = 1;
>
> camera { location  <5*R, 0.1*R, -8*R> look_at <0, 0, 0> angle 20}
>
> sky_sphere { pigment {
>     gradient y
>     color_map { [0.0 color blue 0.6] [1.0 color rgb 1] }
>   }
> }
>
> plane {y,.05 pigment {rgbf .7}}
>
> light_source {<100,200,-100> colour rgb 1}
> light_source {<-100,200,100> colour rgb 1}
>
> plane {y,0
>             pigment {wrinkles // bozo // ripples // granite
>         color_map {
>                    [0   color rgb 0]
>                    [1 color rgb 1]
>
>         } sine_wave phase clock
>       scale .3
>     translate <1, 0, 0>
>     turbulence .1
>     }
>    finish {ambient 1 diffuse 0}
>  rotate -90*x
> }
>
> #declare WaveDepth = 1;
>
> #declare WrinklesFunc =
> function {
>     pigment {wrinkles // bozo // ripples // granite
>         color_map {
>                    [0   color rgb 0]
>                    [1 color rgb 1]
>
>         } sine_wave phase clock
>       scale .3
>     translate <1, 0, 0>
>     turbulence .1
>     }
> }
>
> isosurface {
>     function {
>         y - WrinklesFunc(x,y,z) * WaveDepth/10
>
>       }
>     contained_by{box <-R,-R,-R> <R, R, R>}
>
>
>     pigment {rgb <.2 .2 .9 >}
>     finish {phong 0.5 phong_size 10}
> }
>
>
>

Post a reply to this message