Bill Hails wrote:

> Nice ior demo, nice shape too. sin/cos waves?
Thanks.  Kind of a funny shape.  He calls it a DOR because when you
build one, you can get a "Direct-Opposite-Reflected" image using it
as a lens (the trick is that one of the flat ends works as a mirror
on such projections).

Here's the shape:
#declare tip = function(vert) { sqrt(6.25 - vert*vert) - 1.5 }
#declare rad = function(h) {(h*h+1) / max(h,.000001) / 2}
#declare hgt = function(x,r,h) { sqrt(r*r - x*x) + h - r }
#declare hght= function(x,h) { hgt(x, rad(h), h) }
#declare height=function(x,y) { hght(x, tip(y+1)) }

#declare frontDOR=isosurface {
     function { z * (z - hght(x, tip(y+1))) }
     threshold 0
     max_gradient 30
     contained_by {box {<-1,-1,0>, <1,1,1>}}
     all_intersections
   }

#declare DOR=merge {
   object { frontDOR }
   object { frontDOR rotate <180,0,0> }
   }

> I guess the black areas are deliberate silhouettes
> rather than shadows, however it might be better if
> they weren't so harsh.
They are shadows; the goal was to produce a single high-
quality image that showed his three orthographic views
and displayed the image as an easy-to believe/understand
3-D shape.
I suspect you are right about softening the shadows, but
probably the way to do that is add some fill lighting.

> Is there media in there or just a surface pigment?
No media, only colored lights.

Post a reply to this message