Re: Creating a sphere (Object Graphics)

[davidf(at)dfanning.com (David Fanning)]

Jason P. Meyers (jpm7934@cis.rit.edu) writes:

> 	I have recently taken a plunge into object graphics.  (I think my head
> is still above water but I dunno for sure!)  I spent many hours last
> night trying to create a "simple" (hah!) spherical surface and display
> it using Dave's FSC_Surface program.  (Dave's program was worth its
> weight in Gold, Oops electrons don't weight much do they?)
> 
> 	Anyway, I came up with the procedure listed below which produces 2-D x,
> y, and z arrays which display a sphere.  My problem is that while this
> works for the most part, I can still see some seems and other
> "imperfections" when I rotate the surface in Dave's program.
> 
> 	I was a bit surprised to find that IDL doesn't have a 3-D sphere
> function/procedure up its sleeve.  Nor could I find one at Eric
> Deutsch's IDL web search
> (http://www.astro.washington.edu/deutsch/idl/htmlhelp/index.html).  Does
> anyone know of a better way (or minor improvement) of making a "better
> looking" sphere.  I don't want to spend too much more time on this part
> of my project.  But if I could have a cool shining sphere, that would be
> nice.
> 
> Thanks in advance for any and all suggestions,

Well, I'm sure this was a useful exercise in
and of itself. But I think I might have had
a look at the ORB object that comes in the
IDL examples/objects sub-directory. :-)

   sphere = Obj_New('Orb')

There are other goodies in that directory as well.
RSI has a history of supplying some fabulous,
undocumented code. It's a fair amount of work
to wade through it, but the effort usually pays
off. 

In any case, you ought to have a look through
this directory fairly soon after you start working
with objects.

Cheers,

David

P.S. Let's just say spending many needless hours
writing IDL programs was *exactly* how I became
knowledgeable about IDL. :-)

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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