So this is basically the pov-csg`which is puzzling me: the sphere with radius 4
produces a disproportionally large cylinder compared to the radius 3:
http://home.ooijer.com/povray-conesphereradius3.jpg
http://home.ooijer.com/povray-conesphereradius4.jpg
please note that I didn't change the coordinats of the objects, nor those of the
camera. Yet somehow the sphere seems to swell up enormously, pushing both the
cone and the camera away.
Whe I increaese the sphere's diameter by increments of 0.1 (from 3.0 to 4.5) it
works normally , it's just when I jump from 3 to 4 that this occurs.
This is with v3.62.

#declare FancyPlaycone = object{
//difference{
union{
 cone
 {
  <6,0,0>, 0, <0,0,0>, 4
  //color {Glass}
  pigment{color Red}
  hollow
 }
 /*cone
 {
  <0, 0,-15>, 3, <-2 ,0.0,5>, 3.5
                pigment{color Red}
 }*/
 sphere
 {
         <-3,0,-2>,4
                pigment{color Red}
 }
}
}

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Le 06/10/2010 22:10, Marco a écrit :
> So this is basically the pov-csg`which is puzzling me: the sphere with radius 4
> produces a disproportionally large cylinder compared to the radius 3:
> http://home.ooijer.com/povray-conesphereradius3.jpg
> http://home.ooijer.com/povray-conesphereradius4.jpg

The second link is unavailable.

What is your issue ?

Did you notice that:
 1. you did not provide a full minimalist scene (no camera)
 2. the center of the sphere is not on the center of the cone/disc, ergo
perspective (camera ???) might have some influence.
 3. #declare a=object{union{.. could be simplified to #declare a=union
 4. the posted extract does not use any Blue... so how did you end up
with the first link's image ?
 5. seamless fusion of sphere & cone is not at the sphere's equator.
 (it is at the equator for cylinder, but not for a cone)

-- 
A good Manager will take you
through the forest, no mater what.
A Leader will take time to climb on a
Tree and say 'This is the wrong forest'.

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Marco <rpo### [at] gmailcom> wrote:
> So this is basically the pov-csg`which is puzzling me: the sphere with radius 4
> produces a disproportionally large cylinder compared to the radius 3:
> http://home.ooijer.com/povray-conesphereradius3.jpg
> http://home.ooijer.com/povray-conesphereradius4.jpg

  The latter image is missing, but I can imagine what it looks like.
This is basic geometry and has nothing to do with POV-Ray itself.

  Try drawing on paper a cross-section of the latter image, where the
larger end of the cone perfectly coincides with the meridian of the sphere,
and you'll see why the surface of the cone is not matching with the surface
of the sphere: They are not tangential.

  If you want the surface of the cone to be tangential to the surface of
the sphere, the math is a bit more complicated. Fortunately the standard
library has a macro for that exact purpose, the Connect_Spheres() macro
in shapes.inc. See:

http://wiki.povray.org/content/Documentation:Reference_Section_7.3#shapes.inc

-- 
                                                          - Warp

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