| Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61430] |
Thu, 17 July 2008 08:41  |
humanumbrella
Messages: 52
Registered: June 2008
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Member |
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Hi,
So, I'm trying to make a spherical surface plot with the fsc_surface
class from Dr. Fanning. (:
Fun!
Anyways, I have two arrays, one of latitudes and one of longitudes --
then I have a data array which is lat x long 2D with datapoints.
Here's what I want to do, but have yet to be successful -- and I came
here to look for some tips. : )
Here is what I've tried: so, the surface plotter uses an index
notation for plotting of the datapoints. However, when converting to
spherical data, there will be lat*long x and y values, instead of lat
+long, ie there will no longer be only one lat for all longs, they
will all be different.
I'm using R as the data value that is in the dataset at [lat,long]
So, I'm creating a 2D array that is 2, lat*long
values[0, *] = sin(lat[i])*cos(long[i])*r ;X's
values[1, *] = sin(lat[i])*sin(long[i])*r ; Y's
then I have datapoints = lat*long
so now, I have the x's and y's I need, but I need to plot them as a
surface.
it will be,
plot
datapoints[0] at x[0]y[0]
...
datapoints[n] at x[n]y[n] where n = lat*long
Should I try to go about using volume for this spherical surface
plot ?
Thanks for any suggestions!
Cheers,
--Justin
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61525 is a reply to message #61430] |
Mon, 21 July 2008 13:35  |
humanumbrella
Messages: 52
Registered: June 2008
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Member |
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On Jul 21, 4:31 pm, David Fanning <n...@dfanning.com> wrote:
> Justin writes:
>> Here's a video of my animation of FSC_surface as well as what I will
>> eventually include with fsc_surface, that is the spherical surface
>> polygon. It's 10MB though, so be patient. (:
>> Check it out -->http://csserver04.furman.edu/Research/ResearchBlogs/justin=
>> /interp-beta.htm
>
> Wow. How about writing an article for my web page on
> how to create a video like that? :-)
>
> Cheers,
>
> David
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
It's really easy -- there's a free program called "Wink" by
"Debugmode" -- It's open source and it allows you to create a custom
box for recording -- it is very powerful, but I only use the basics.
(: Record (via taking screenshots at a set frames/sec), then export
to flash -- it will even add that little preloader on there for you!
(: Check it out. http://www.debugmode.com/wink/
Cheers!
--Justin
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61527 is a reply to message #61430] |
Mon, 21 July 2008 13:21 |
humanumbrella
Messages: 52
Registered: June 2008
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Member |
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On Jul 21, 10:22 am, David Fanning <n...@dfanning.com> wrote:
> humanumbre...@gmail.com writes:
>> I use square brackets. (: The code I pasted is code I found on the
>> Internets.
>
> Well, I can believe that! And this is surely not the
> worst of it. ;-)
>
> Cheers,
>
> David
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Thanks Rick for that e-mail about the clipping! (:
Here's a video of my animation of FSC_surface as well as what I will
eventually include with fsc_surface, that is the spherical surface
polygon. It's 10MB though, so be patient. (:
Check it out --> http://csserver04.furman.edu/Research/ResearchBlogs/justin/i nterp-beta.htm
Cheers,
--Justin
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61532 is a reply to message #61430] |
Mon, 21 July 2008 07:14 |
humanumbrella
Messages: 52
Registered: June 2008
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Member |
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On Jul 21, 10:04 am, David Fanning <n...@dfanning.com> wrote:
> humanumbre...@gmail.com writes:
>> Also -- for others who follow, here's some help, not with fsc_Surface
>> in particular, but with surface plots, for a way of displaying
>> spherical data, though the author (who had correspondence with Dr.
>> Fanning, hehe) is experiencing a problem with a hole in the plot.
>
> I've learned quite a lot after my tip to Justin that this
> "couldn't be done". :-(
>
> Just one piece of advice, though. Put the compile option
> idl2 in all your code. You are writing programs that a lot
> of other people are not going to be able to compile.
>
> compile_opt idl2
>
> This will force you to use square brackets for array
> subscripting, a practice everyone on the planet ought to
> be using by now. :-)
>
> Cheers,
>
> David
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
> This will force you to use square brackets for array
> subscripting, a practice everyone on the planet ought to
> be using by now. :-)
I use square brackets. (: The code I pasted is code I found on the
Internets.
Cheers,
--Justin
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61533 is a reply to message #61430] |
Mon, 21 July 2008 07:04 |
David Fanning
Messages: 11724
Registered: August 2001
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Senior Member |
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humanumbrella@gmail.com writes:
> Also -- for others who follow, here's some help, not with fsc_Surface
> in particular, but with surface plots, for a way of displaying
> spherical data, though the author (who had correspondence with Dr.
> Fanning, hehe) is experiencing a problem with a hole in the plot.
I've learned quite a lot after my tip to Justin that this
"couldn't be done". :-(
Just one piece of advice, though. Put the compile option
idl2 in all your code. You are writing programs that a lot
of other people are not going to be able to compile.
compile_opt idl2
This will force you to use square brackets for array
subscripting, a practice everyone on the planet ought to
be using by now. :-)
Cheers,
David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61534 is a reply to message #61430] |
Mon, 21 July 2008 06:46 |
humanumbrella
Messages: 52
Registered: June 2008
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Member |
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Hello everyone,
Sorry I have not responded for a couple of days, I've been up in
Washington DC on vacation, hehe.
Anyway, I see the clipping which David references on my machine using
IDL7.0.
Here's the screen -> http://tinyurl.com/696ro2
Also -- for others who follow, here's some help, not with fsc_Surface
in particular, but with surface plots, for a way of displaying
spherical data, though the author (who had correspondence with Dr.
Fanning, hehe) is experiencing a problem with a hole in the plot.
ang=transpose(2*!PI*findgen(64)/63)
print, ang
n=size(ang, /N_ELEMENTS )
print, n
ones=fltarr(n,1)+1
theta_a=(ang##ones)
print, size(theta_a)
;ang2=[0:.05:pi+.05]'-pi/2; (this is what Iused in Matlab)
ang2=transpose(!PI*findgen(n)/(n-1)-!PI/2) ; (should be roughly
equivalent to above)
theta_e=transpose(ang2##ones)
rcart=1+cos(!pi/2-theta_e)
theta_a_1d=reform(theta_a,1,n*n)
print, size(theta_a_1d)
theta_e_1d=reform(theta_e,1,n*n)
print, size(theta_e_1d)
rcart_1d=reform(rcart,1,n*n)
print, size(rcart_1d)
sph=[theta_a_1d,theta_e_1d,rcart_1d]
rectc=cv_coord(from_sphere=sph, /to_rect)
x_1d=rectc(0,*)
y_1d=rectc(1,*)
z_1d=rectc(2,*)
x=reform(x_1d,n,n)
y=reform(y_1d,n,n)
z=reform(z_1d,n,n)
print, size(z)
isurface, z,x,y
xplot3d, x,y,z
I think this is well enough to get me on my way today!
Thanks everyone!
Cheers,
--Justin
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61551 is a reply to message #61430] |
Fri, 18 July 2008 23:44 |
Andrew Cool
Messages: 219
Registered: January 1996
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Senior Member |
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On Jul 19, 3:19 pm, Andrew Cool <andrew.c...@dsto.defence.gov.au>
wrote:
> On Jul 19, 12:36 pm, David Fanning <n...@dfanning.com> wrote:
>
>
>
>> Andrew Cool writes:
>>> Is this a graphics card/OPENGL issue? Time for you to update that P3
>>> 800Mhz PC with the TNT Riva 16MB card?
>
>> I have the best graphics card I could install on my ancient
>> computer without gutting the insides and installing a new
>> air conditioner in there to keep the darn graphics card happy.
>> NVIDIA GEFORCE 7600 GT. I guess there is a new driver for it,
>> and I'm downloading it now, but I see the hole in both IDL 6.4 and
>> IDL 7.0.3, with both hardware and software (always my default)
>> rendering selected.
>
>> If the driver doesn't help, I'll send pictures. Not as cute
>> as your soccer-playing daughter, but still...
>
>> Cheers,
>
>> David
>> --
>> David Fanning, Ph.D.
>> Fanning Software Consulting, Inc.
>> Coyote's Guide to IDL Programming:http://www.dfanning.com/
>> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
>
> I'll show you mine if ...
>
> http://www.cool.id.au/IDL/exaggerated%20earth.jpg
>
> A.
David,
I've installed IDL 7.0 off the disk, and I *do* see your mysterious
holes in the Himalayas and in the high plateaus of
the Antartic (not the South Pole, but the high mountains surrounding
he pole.)
Now that I know what you're talking about, I continue to be puzzled
that I *do not* see the same effect under IDL 6.4,
but you do.
I have to find something better to do on a cold, wet Saturday
arvo... ;-)
A.
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61552 is a reply to message #61430] |
Fri, 18 July 2008 23:19 |
Andrew Cool
Messages: 219
Registered: January 1996
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Senior Member |
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On Jul 19, 12:36 pm, David Fanning <n...@dfanning.com> wrote:
> Andrew Cool writes:
>> Is this a graphics card/OPENGL issue? Time for you to update that P3
>> 800Mhz PC with the TNT Riva 16MB card?
>
> I have the best graphics card I could install on my ancient
> computer without gutting the insides and installing a new
> air conditioner in there to keep the darn graphics card happy.
> NVIDIA GEFORCE 7600 GT. I guess there is a new driver for it,
> and I'm downloading it now, but I see the hole in both IDL 6.4 and
> IDL 7.0.3, with both hardware and software (always my default)
> rendering selected.
>
> If the driver doesn't help, I'll send pictures. Not as cute
> as your soccer-playing daughter, but still...
>
> Cheers,
>
> David
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
I'll show you mine if ...
http://www.cool.id.au/IDL/exaggerated%20earth.jpg
A.
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61554 is a reply to message #61430] |
Fri, 18 July 2008 20:04 |
Andrew Cool
Messages: 219
Registered: January 1996
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Senior Member |
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On Jul 19, 8:39 am, David Fanning <n...@dfanning.com> wrote:
> Andrew_Cool writes:
>> You've had one too many? I see no defects at all, even the poles are
>> solidly closed.
>
>> Leave the pimento alone - it must be rotten after so many years.
>
> Yeah, it wasn't the pimento, but there definitely is some
> near-plane clipping going on with my machine. I can see a
> small clipped hole on most of the image, but it becomes
> especially apparent, and large enough to look through to
> the other side of the earth, when I look at the Himalayan
> region. They sort of just disappear when I rotate them
> into the center of the view.
I've just checked again. Enlarged the XObjView window to desktop
height, and rotated the globe every which way.
Zoomed in, zoomed out, I don't see any gaps/artefects anywhere.
And that's with either Hardware or Software selected in Prefs.
OK, the poles look a little like puckered up arseholes, but they're
tight litle arseholes with no room for leakage... ;-)
I'm running this under Windows, IDL v6.4. with an NVidia 8800GTS card.
How about emailing me a screen dump of your Holey Himalayas?
Is this a graphics card/OPENGL issue? Time for you to update that P3
800Mhz PC with the TNT Riva 16MB card?
> Don't get your hopes up too high. My brother just had to close
> his photography business because of people like you. ;-)
Ah, having paid out thousands to send my kid to an interstate sporting
competition, along come people like your brother
who charge like wounded bulls for stock standard team photos. No
bloody wonder he's gone broke without a captive market anymore... ;-)
Andrew
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61559 is a reply to message #61430] |
Fri, 18 July 2008 16:39 |
David Fanning
Messages: 11724
Registered: August 2001
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Senior Member |
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Andrew_Cool writes:
> You've had one too many? I see no defects at all, even the poles are
> solidly closed.
>
> Leave the pimento alone - it must be rotten after so many years.
Yeah, it wasn't the pimento, but there definitely is some
near-plane clipping going on with my machine. I can see a
small clipped hole on most of the image, but it becomes
especially apparent, and large enough to look through to
the other side of the earth, when I look at the Himalayan
region. They sort of just disappear when I rotate them
into the center of the view.
> Umm, that was pushing midnight. I've been reworking the code for that
> sports team photo I sent you.
Don't get your hopes up too high. My brother just had to close
his photography business because of people like you. ;-)
Cheers,
David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
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| Re: Spherical Surface Plot w/ fsc_surface from David Fanning (: [message #61560 is a reply to message #61481] |
Fri, 18 July 2008 16:21 |
pook41
Messages: 16
Registered: January 2007
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Junior Member |
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On Jul 18, 11:19 pm, David Fanning <n...@dfanning.com> wrote:
> Andrew Cool writes:
>> Here's an adaption of some code that I think originally came from
>> someone inside RSI long ago - I forget just who it was.
>
> Jim Pendleton, no doubt.
No, I think it was one of the many RSI guys with the initials AC, one
of the Adam's maybe.
> You can really see that pimento effect if you looks though the Himalayas. Why do you suppose
> that is happening?
You've had one too many? I see no defects at all, even the poles are
solidly closed.
Leave the pimento alone - it must be rotten after so many years.
>
> P.S. What time *is* it in Australia, Andrew. I don't usually
> talk to you at 7:00 AM, Colorado time!
Umm, that was pushing midnight. I've been reworking the code for that
sports team photo I sent you.
Cheers,
Andrew
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| Re: Spherical surface plot [message #66305 is a reply to message #61430] |
Sun, 03 May 2009 20:42 |
Mrunmayee
Messages: 24
Registered: May 2009
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Junior Member |
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On May 4, 3:20 am, David Fanning <n...@dfanning.com> wrote:
> Mrunmayee writes:
>> If I am not beating the dead horse here, what *kind* of surface am I
>> trying to display? I thought I was trying to do a straight forward
>> surface plot!
>
> I think you are trying to display a 3D surface. The IDL Surface
> command is designed to display a 2D surface in a 3D representation
> (I.e, a 2.5D surface). You might have more luck in direct graphics
> if you represented your 3D surface as a volume and tried to display
> an isosurface of that. (If that is what you want, it is not clear
> to me.)
>
>> Actually, I haven't tried to iSurface, forgot about it. I don't like
>> to use it, because it invariably crashes my x-server.
>
> Yeah, well, there is that. :^)
>
> Cheers,
>
> David
>
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
How is it a 3D surface? It's only specified by \theta and \phi
coordinates, so shouldn't it be 2D?
Will see what happens with displaying it as an isosurface.
-Gauri.
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| Re: Spherical surface plot [message #66310 is a reply to message #61430] |
Sun, 03 May 2009 15:20 |
David Fanning
Messages: 11724
Registered: August 2001
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Senior Member |
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Mrunmayee writes:
> If I am not beating the dead horse here, what *kind* of surface am I
> trying to display? I thought I was trying to do a straight forward
> surface plot!
I think you are trying to display a 3D surface. The IDL Surface
command is designed to display a 2D surface in a 3D representation
(I.e, a 2.5D surface). You might have more luck in direct graphics
if you represented your 3D surface as a volume and tried to display
an isosurface of that. (If that is what you want, it is not clear
to me.)
> Actually, I haven't tried to iSurface, forgot about it. I don't like
> to use it, because it invariably crashes my x-server.
Yeah, well, there is that. :^)
Cheers,
David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
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| Re: Spherical surface plot [message #66314 is a reply to message #61430] |
Sun, 03 May 2009 10:44 |
Mrunmayee
Messages: 24
Registered: May 2009
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Junior Member |
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On May 3, 7:00 pm, David Fanning <n...@dfanning.com> wrote:
> Mrunmayee writes:
>> Oh man... I have never ventured into objects in IDL. Not much idea
>> about 2.5D and 3D rendering. So, when you use OBJ_NEW("IDLGrSurface"),
>> it uses 3D rendering?
>
>> But as to what is happening here. See if doing following shines any
>> new light.
>
> Well, it probably confirms that the surface algorithm
> used in the direct graphics surface command was state
> of the art 30 years ago. Personally, I don't think it
> was designed to display the kind of surface you appear
> determined to display. Time to learn about object
> graphics, I'd say. :-)
>
> Cheers,
>
> David
>
> P.S. Have you tried the iSurface tool? No one will be
> able to help you program the darn thing, but maybe it
> will do your display correctly.
>
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
If I am not beating the dead horse here, what *kind* of surface am I
trying to display? I thought I was trying to do a straight forward
surface plot!
Actually, I haven't tried to iSurface, forgot about it. I don't like
to use it, because it invariably crashes my x-server. Nonetheless, I
will see what it does.
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| Re: Spherical surface plot [message #66315 is a reply to message #61430] |
Sun, 03 May 2009 07:00 |
David Fanning
Messages: 11724
Registered: August 2001
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Senior Member |
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Mrunmayee writes:
> Oh man... I have never ventured into objects in IDL. Not much idea
> about 2.5D and 3D rendering. So, when you use OBJ_NEW("IDLGrSurface"),
> it uses 3D rendering?
>
> But as to what is happening here. See if doing following shines any
> new light.
Well, it probably confirms that the surface algorithm
used in the direct graphics surface command was state
of the art 30 years ago. Personally, I don't think it
was designed to display the kind of surface you appear
determined to display. Time to learn about object
graphics, I'd say. :-)
Cheers,
David
P.S. Have you tried the iSurface tool? No one will be
able to help you program the darn thing, but maybe it
will do your display correctly.
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
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| Re: Spherical surface plot [message #66316 is a reply to message #61430] |
Sun, 03 May 2009 05:50 |
Mrunmayee
Messages: 24
Registered: May 2009
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Junior Member |
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On May 2, 6:52 pm, David Fanning <n...@dfanning.com> wrote:
> Mrunmayee writes:
>> I have been trying to create a spherical surface plot and have
>> partially succeeded. Here is what I did to create a surface:
>> theta3 = findgen(361)/2. * !pi/180. ; 0<= theta <= !pi
>> phi3 = findgen(361) * !pi/180. ; 0<= phi <= 2*!pi
>> x3 = sin(theta3) # cos(phi3)
>> y3 = sin(theta3) # sin(phi3)
>> sph = sqrt( (1. - x3^2 - y3^2) > 0.) ; This is to avoid
>> "floating illegal operand" error.
>> sph1 = sph ; Just for comparison
>> with sph, to be modified as follows
>> sph2 = sph[181:360,*] ; Array containing
>> elements for !pi/2 < theta <= !pi i.e. southern hemisphere
>> sph1[181:360,*] = -sph2 ; Since sqrt will just take
>> +ve root, this inverts and creates southern hemisphere.
>
>> Success: fsc_surface, sph1, x3, y3 ; Glorious spherical surface
>> surface, sph1, x3, y3 ; Rather pathetic
>> rendering of surface but still a spherical surface
>> Failure: shade_surf, sph1, x3, y3 ; Nothing viewd. NOTHING AT
>> ALL. Whether device, decomposed=0/1 doesn't matter.
>
>> Anyone knows what's happening?
>
> I don't know what is happening, but the result doesn't
> surprise me much. SURFACE and SHADE_SURF use what is
> technically referred to as a "two and a half D" surface
> rendering engine. All direct graphics commands use this
> 2.5D way of rendering 3D objects. Object graphics, which
> is what FSC_SURFACE is using, uses a true 3D rendering
> engine. I would have expected it to be better at rendering
> this surface.
>
> I think the bottom line is that if you *really* want to
> do 3D things, you will have to do them in object graphics
> if you want "modern" (as opposed to state of the art in the
> 1970s) 3D results.
>
> Cheers,
>
> David
>
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming:http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Oh man... I have never ventured into objects in IDL. Not much idea
about 2.5D and 3D rendering. So, when you use OBJ_NEW("IDLGrSurface"),
it uses 3D rendering?
But as to what is happening here. See if doing following shines any
new light.
;Continuing variables from above:
;----------------------------------------------
sphn = sph[0:180, *] & xn = x3[0:180, *] & yn = y3[0:180, *] ;North
hemisphere and coordinates
sphs = -sph[181:360, *] & xs = x3[181:360, *] & ys = [181:360, * ] ;
South hemisphere and coords
surface, sph1, x3, y3, ax=0, az=0 ; This projection is uber-
horrible. In this, whole eastern hemisphere is missing.
surface, sphn, xn, yn, ax=0, az=0 ; Nothing of the sort.
surface, sphs, xs, ys, ax=0, az=0 ; Again, nothing missing!
Thanks for replying.
Gauri.
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| Re: Spherical surface plot [message #66320 is a reply to message #61430] |
Sat, 02 May 2009 06:52 |
David Fanning
Messages: 11724
Registered: August 2001
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Senior Member |
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Mrunmayee writes:
> I have been trying to create a spherical surface plot and have
> partially succeeded. Here is what I did to create a surface:
> theta3 = findgen(361)/2. * !pi/180. ; 0<= theta <= !pi
> phi3 = findgen(361) * !pi/180. ; 0<= phi <= 2*!pi
> x3 = sin(theta3) # cos(phi3)
> y3 = sin(theta3) # sin(phi3)
> sph = sqrt( (1. - x3^2 - y3^2) > 0.) ; This is to avoid
> "floating illegal operand" error.
> sph1 = sph ; Just for comparison
> with sph, to be modified as follows
> sph2 = sph[181:360,*] ; Array containing
> elements for !pi/2 < theta <= !pi i.e. southern hemisphere
> sph1[181:360,*] = -sph2 ; Since sqrt will just take
> +ve root, this inverts and creates southern hemisphere.
>
> Success: fsc_surface, sph1, x3, y3 ; Glorious spherical surface
> surface, sph1, x3, y3 ; Rather pathetic
> rendering of surface but still a spherical surface
> Failure: shade_surf, sph1, x3, y3 ; Nothing viewd. NOTHING AT
> ALL. Whether device, decomposed=0/1 doesn't matter.
>
> Anyone knows what's happening?
I don't know what is happening, but the result doesn't
surprise me much. SURFACE and SHADE_SURF use what is
technically referred to as a "two and a half D" surface
rendering engine. All direct graphics commands use this
2.5D way of rendering 3D objects. Object graphics, which
is what FSC_SURFACE is using, uses a true 3D rendering
engine. I would have expected it to be better at rendering
this surface.
I think the bottom line is that if you *really* want to
do 3D things, you will have to do them in object graphics
if you want "modern" (as opposed to state of the art in the
1970s) 3D results.
Cheers,
David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
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