> 
> Please look at this and check it:
> 
> To create a drop, I used a quartic as described in the scene
> below, and to see the effect of varying the threshold constant
> T, I "differenced" this with a drop having T=0, which should
> give an hollow object similar to a drop-shaped soap bubble.
> But I saw strange effects I couldn't understand.
> 
> [...]

In POV-Ray 3.5 try using:

#macro Drop ( T )   
  isosurface {
    function { pow(x, 4)-pow(x, 3)+y*y+z*z-T }    
    max_gradient 0.5 
    accuracy 0.0001
    contained_by { box { -0.06, 0.06 } }
  }     
#end//macro Drop

You might have to vary the container object and the max_gradient and
accuracy parameters to your specific configuration.

Concerning your observation: You should not expect the root solver to work
perfectly under all conditions.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

Post a reply to this message