Re: surface elements for transparent_solids.dem

[Daniel J S. <dan...@ie...>]

Daniel J Sebald wrote:
> Daniel J Sebald wrote:
> 
>>One thing I notice when the fill is solid is that along some of the
>>edges of the Kuen's surface example are some oddly shaped surface
>>elements.

I'm pretty certain this is a bug; there are some elements from a hidden
surface for some reason being mixed in with the elements from the visible
surface.  Hidden lines works as it should.  To verify this, run the
transparent_solids.dem file three times in X11 creating a new window each
time so the various Kuen surface plots can be compared.

load 'transparent_solids.dem'
(hit return twice)
(
change
  splot x(u,v), y(u,v), z(u,v) with pm3d
to
  splot x(u,v), y(u,v), z(u,v) with lines
in transparent_solids.dem'
)
set term x11 2
load 'transparent_solids.dem'
(hit return twice)
(
add
  unset hidden3d
  splot x(u,v), y(u,v), z(u,v) with lines
in transparent_solids.dem'
)
set term x11 3
load 'transparent_solids.dem'
(hit return twice)

I believe the second plot with hidden lines but no pm3d elements looks
correct.  Now, if one looks at the third plot with the quadrangles from
what would be hidden surfaces, these match the geometry of the few
quadrangles in the first "hidden3d pm3d" plot.

It would be nice to fix this for 4.2 (don't want the flagship figures hilighting flaws).  This seems like it would be but a line or two alteration.  Anyone?

Dan