[Radiance-general] Re: Radiance-general digest, Vol 1 #54 - 9 msgs

Zack Rogers [email protected]
Wed, 30 Jan 2002 11:09:12 -0700


On the topics of trees and water....I have attempted to tackle both of these in recent models and thought I throw in my two cents.

I guess it already been said that the best way to add trees to your model is by creating an octree for each type of tree and adding them to you model as an instance,
I agree.  I recently attempted to model a indoor Tropical Rain Forest.  For this I had 20 or so different types of trees.  I made octrees for each type and inserted
them into my model using instances, some of the octrees as large as 9.7MB.  Without using instances the resulting model octree would have been gigantic.  Using
instances the resulting octree was about 5.9MB, still pretty large but much more reasonable.  To confirm what Judy has said, with the backwards ray-tracing technique
used by Radiance, ridiculously complex geometry does not necessarily mean ridiculously long rendering times.  I did not exclude the trees from the ambient
calculation and a single image of this rainforest, using medium rendering quality and 2 ambient bounces, rendered in several hours on my 950MHz computer.  Radiance
is amazing!  These images can be seen at:

http://www.archenergy.com/sda/designtools/radiance.html  ---> Phipps

As far as modeling water, I recently tried to tackle this for a glare study on an indoor pool.  I modeled the water using the ripple.cal function, as follows;

void texfunc water_1
6 riple_x riple_y riple_z ripple.cal -s 1
0
4 .13 .13 0 .13

water_1  BRTDfunc Water
10      rrho    grho    brho
          rtau     gtau    btau
          0 0 0
          water.cal
0
18      0       0       0
          0       0       0
          0       0       0
          1 1 1
          1 1 1
          .7 .90 .90

Where water.cal is just a slightly modified glazing.cal function.  I was attempting to better model the transmittance and reflectance vs. incidence angle
characteristics of water.  This is not the most accurate way to model water and I would not use this if any underwater calculations are needed.  I think the most
accurate way to model water is to use a diaelectric.  I have not tried this but have heard it makes for long simulation times.  The images of the pool can also be
seen at;

http://www.archenergy.com/sda/designtools/radiance.html  ---> Chilson

Hope this helps!
Zack

[email protected] wrote:

> Send Radiance-general mailing list submissions to
>         [email protected]
>
> To subscribe or unsubscribe via the World Wide Web, visit
>         http://www.radiance-online.org/mailman/listinfo/radiance-general
> or, via email, send a message with subject or body 'help' to
>         [email protected]
>
> You can reach the person managing the list at
>         [email protected]
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Radiance-general digest..."
>
> Today's Topics:
>
>    1. Re: Re: Trees... and defining them in radiance (Lars O. Grobe) (Lars O. Grobe)
>    2. syntax of wrinkle.cal (or: how to get a nice water surface) (Lars O. Grobe)
>    3. Re: Re: Trees... and defining them in radiance (Lars O. Grobe) (Lars O. Grobe)
>    4. Re: syntax of wrinkle.cal (or: how to get a nice
>        water surface) (atelier iebele abel)
>    5. Re: Re: Trees... and defining them in radiance (Georg Mischler)
>    6. macbethcal and pcond (Lars O. Grobe)
>    7. compiling the 3.4b on alpha linux (Lars O. Grobe)
>    8. Re: Radiance 3.4 release (Greg Ward)
>
> --__--__--
>
> Message: 1
> From: "Lars O. Grobe" <[email protected]>
> To: [email protected]
> Subject: Re: [Radiance-general] Re: Trees... and defining them in radiance (Lars O. Grobe)
> Date: Tue, 29 Jan 2002 13:07:20 +0100
> Reply-To: [email protected]
>
> Hi!
>
> > The best advice is probably to exclude the tree geometry from the
> > ambient calculation as mentioned in another reply. Unfortunately
> > this is not yet directly supported by the Rayfront interface
> > (which Lars is using), but you can still add the necessary
> > parameters to the rif file manually. Rayfront will preserve those
> > entries when reading the file, and correctly pass them to rpict
> > and friends, even if it doesn't expose them in the GUI.
>
> In fact, I am currently working on the scene without rayfront. Is there a way
> to make rayfront generate one octree per imported geometry (I used
> rad-geometries, but the dxf-import would be ok, too)? If I try to oconv all
> my rad-files in one run, I get the famous oconv overflow ;-) So I created one
> oct per "object" (in fact per color) and have a instance file "model.rad"
> where I put all my octs together.
>
> CU, Lars.
>
> --__--__--
>
> Message: 2
> From: "Lars O. Grobe" <[email protected]>
> To: [email protected]
> Date: Tue, 29 Jan 2002 13:10:10 +0100
> Subject: [Radiance-general] syntax of wrinkle.cal (or: how to get a nice water surface)
> Reply-To: [email protected]
>
> Hi!
>
> I try to get a nice water surface. I wanted to try wrinkle.cal, but I don't
> understand the syntax. Is there anyone who has an example how to use it?
>
> So far, I use the wobbly.cal with a glass material, but this doesn't seam to
> be the best choice.
>
> Thank You, CU, Lars.
>
> --__--__--
>
> Message: 3
> From: "Lars O. Grobe" <[email protected]>
> To: [email protected]
> Subject: Re: [Radiance-general] Re: Trees... and defining them in radiance (Lars O. Grobe)
> Date: Tue, 29 Jan 2002 13:03:27 +0100
> Reply-To: [email protected]
>
> Hi!
>
> > To define trees in Radiance, you can either use an impostor as you do in
> > your CAD system, and apply a "colorpict" to it, or (as I prefer), model
> > the tree as detailed geometry and compile into an octree for the
> > "instance" primitive.
>
> I used geometry now, with replmarks and instances on 3r4b. Works fine, thank
> you for your reply. In fact, I get the quite large model rendered on my old
> laptop with 128 MB...
>
> CU, Lars.
>
> --__--__--
>
> Message: 4
> Date: Tue, 29 Jan 2002 16:16:09 +0100
> From: atelier iebele abel <[email protected]>
> Organization: atelier iebele abel
> To: [email protected]
> Subject: Re: [Radiance-general] syntax of wrinkle.cal (or: how to get a nice
>  water surface)
> Reply-To: [email protected]
>
> --------------CC29D4672F89C939A4CEDED3
> Content-Type: text/plain; charset=us-ascii
> Content-Transfer-Encoding: 7bit
>
> Hi  Lars,
>
> This works for me, good luck!
>
> Regards,
>
> Iebele
>
> # Model the water as a single surface.
> # Below the water should be a dark open box,
> # 'just like' as in the real world.
> # See the ascii art below...
> #
> #         section of the scene
> #
> #        ~~~~~~~~~~~~~~~~~~~~~   bumpy water surface
> #        \                   /   dark box
> #         \_________________/
> #
>
> void texfunc bumpy
> 6 xwrink ywrink zwrink wrinkle.cal -s 2.2
> 0
> 3 0.01 0.05 0.05
>
> bumpy glass water
> 0
> 0
> 3 0.3 0.3 0.3
>
> #water is the modifier
>
> "Lars O. Grobe" wrote:
>
> > Hi!
> >
> > I try to get a nice water surface. I wanted to try wrinkle.cal, but I don't
> > understand the syntax. Is there anyone who has an example how to use it?
> >
> > So far, I use the wobbly.cal with a glass material, but this doesn't seam to
> > be the best choice.
> >
> > Thank You, CU, Lars.
> > _______________________________________________
> > Radiance-general mailing list
> > [email protected]
> > http://www.radiance-online.org/mailman/listinfo/radiance-general
>
> --------------CC29D4672F89C939A4CEDED3
> Content-Type: text/html; charset=us-ascii
> Content-Transfer-Encoding: 7bit
>
> <!doctype html public "-//w3c//dtd html 4.0 transitional//en">
> <html>
> <tt></tt>&nbsp;
> <br><tt>Hi&nbsp; Lars,</tt><tt></tt>
> <p><tt>This works for me, good luck!</tt><tt></tt>
> <p><tt>Regards,</tt><tt></tt>
> <p><tt>Iebele</tt>
> <br><tt></tt>&nbsp;<tt></tt>
> <p><tt># Model the water as a single surface.</tt>
> <br><tt># Below the water should be a dark open box,</tt>
> <br><tt># 'just like' as in the real world.</tt>
> <br><tt># See the ascii art below...</tt>
> <br><tt>#</tt>
> <br><tt>#&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; section of the
> scene</tt>
> <br><tt>#</tt>
> <br><tt>#&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ~~~~~~~~~~~~~~~~~~~~~&nbsp;&nbsp;
> bumpy water surface</tt>
> <br><tt>#&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; \&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
> /&nbsp;&nbsp; dark box</tt>
> <br><tt>#&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; \_________________/</tt>
> <br><tt>#</tt>
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;<tt></tt>
> <p><tt>void texfunc bumpy</tt>
> <br><tt>6 xwrink ywrink zwrink wrinkle.cal -s 2.2</tt>
> <br><tt>0</tt>
> <br><tt>3 0.01 0.05 0.05</tt><tt></tt>
> <p><tt>bumpy glass water</tt>
> <br><tt>0</tt>
> <br><tt>0</tt>
> <br><tt>3 0.3 0.3 0.3</tt><tt></tt>
> <p><tt>#water is the modifier</tt>
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;
> <br><tt></tt>&nbsp;<tt></tt>
> <p>"Lars O. Grobe" wrote:
> <blockquote TYPE=CITE>Hi!
> <p>I try to get a nice water surface. I wanted to try wrinkle.cal, but
> I don't
> <br>understand the syntax. Is there anyone who has an example how to use
> it?
> <p>So far, I use the wobbly.cal with a glass material, but this doesn't
> seam to
> <br>be the best choice.
> <p>Thank You, CU, Lars.
> <br>_______________________________________________
> <br>Radiance-general mailing list
> <br>[email protected]
> <br><a href="http://www.radiance-online.org/mailman/listinfo/radiance-general">http://www.radiance-online.org/mailman/listinfo/radiance-general</a></blockquote>
> </html>
>
> --------------CC29D4672F89C939A4CEDED3--
>
> --__--__--
>
> Message: 5
> Date: Tue, 29 Jan 2002 15:59:23 -0500 (EST)
> From: Georg Mischler <[email protected]>
> To: <[email protected]>
> Subject: Re: [Radiance-general] Re: Trees... and defining them in radiance
> Reply-To: [email protected]
>
> Lars O. Grobe wrote:
>
> > In fact, I am currently working on the scene without rayfront. Is there a way
> > to make rayfront generate one octree per imported geometry (I used
> > rad-geometries, but the dxf-import would be ok, too)? If I try to oconv all
> > my rad-files in one run, I get the famous oconv overflow ;-) So I created one
> > oct per "object" (in fact per color) and have a instance file "model.rad"
> > where I put all my octs together.
>
> There currently is no automatic way. You can place octrees in the
> "parts" directory in the project, and include them with the marker
> substitution feature. This is slightly clumsy, and primarily interesting
> for those parts of your model that contribute a lot to the complexity,
> but probably won't change later. The details of the procedure are
> more suitable for a different mailing list, though.
>
> Future versions of Rayfront may offer to do this automatically.
>
> -schorsch
>
> --
> Georg Mischler  --  simulations developer  --  schorsch at schorsch.com
> +schorsch.com+  --  lighting design tools  --  http://www.schorsch.com/
>
> --__--__--
>
> Message: 6
> From: "Lars O. Grobe" <[email protected]>
> To: [email protected]
> Date: Tue, 29 Jan 2002 23:49:55 +0100
> Subject: [Radiance-general] macbethcal and pcond
> Reply-To: [email protected]
>
> Hi!
>
> Again me... I'm spending quite a lot of time with radiance at the moment ;-)
>
> I want to print some renderings on a large format printer. If I simply print
> a tiff (generated with ra_tiff), I get very bad colors (not enough
> saturation, everything appears grey).
>
> No I tried the macbethcal. I printed the macbeth-pic from the distribution
> (using the same print chain as I will do with the rendering), scanned it with
> an xrite 41, calculated xyY from x-rite's xyz-data (is there a converter /
> script to do this out there???), made a cal-file (with some warning
> concerning gamut of intermediate colors). But pcond says "cannot grok
> macbethcal file", and something about inp-flags 077. What does it mean?
>
> Maybe someone may help? So long, I must use photoshop ;-)
>
> CU, Lars.
>
> --__--__--
>
> Message: 7
> From: "Lars O. Grobe" <[email protected]>
> To: [email protected]
> Date: Wed, 30 Jan 2002 00:00:01 +0100
> Subject: [Radiance-general] compiling the 3.4b on alpha linux
> Reply-To: [email protected]
>
> Hi!
>
> Did anyone successfully use the 3.4 or it's beta on alpha / linux?
>
> While I got it to compile (with compaq c 6.2), radianc doesn't want to render
> ;-) It's oconv giving me always out of memory messages (e.g. with the
> "benchmark2", available at Mark Stock's pages).
>
> Did the oconv code change? I have been using 3r2 on alpha with compaq c for
> linux before.
>
> CU, Lars.
>
> --__--__--
>
> Message: 8
> Date: Tue, 29 Jan 2002 14:36:55 -0800
> From: Greg Ward <[email protected]>
> To: [email protected]
> Subject: [Radiance-general] Re: Radiance 3.4 release
> Reply-To: [email protected]
>
> Good point about using the mixpict primitive -- I vaguely remembered
> programming something like this, but then didn't see it in the ray.html
> reference manual, so I thought I must have dreamed it.  I guess it's one
> of those things that didn't get updated when it should have because I
> wasn't sure that it was in the LBNL release or not.  Now that it's there
> in 3.4, I went and updated the HTML reference manual, but I know there
> are still a lot of man pages on the website that are in need of
> updating...  Unfortunately, I don't have any of the tools I onced used
> to convert nroff into HTML and PostScript.  Sigh.  Guess that's
> something to do in my "free" time.  If something seems inconsistent,
> it's best to rely on what's in ray/man/man1 in the 3.4 distribution.
>
> I just compiled 3.4 for SGI machines, since most systems come without a
> compiler license these days.  John Mardaljevic also reminded me that
> there is a problem getting the TIFF library to compile under Solaris.
> The "install" program on some Solaris systems seems to be broken, so the
> TIFF library fails to install properly, and the rest of the programs in
> the src/px directory don't get installed as a consequence.  This can be
> remedied by manually installing the library from src/px/tiff/libtiff
> into src/lib, but it's too bad I don't know of a better fix than this.
>
> I'm still planning to compile under Intel Linux, and will probably get
> to that in the next day or two.  If Lars beats me to it and sends me the
> binaries, so much the better!
>
> -Greg
>
> --__--__--
>
> _______________________________________________
> Radiance-general mailing list
> [email protected]
> http://www.radiance-online.org/mailman/listinfo/radiance-general
>
> End of Radiance-general Digest

--
Zack Rogers
Sustainable Designer/Associate Engineer
Architectural Energy Corporation
2540 Frontier Avenue, Suite 201
Boulder, CO 80301 USA
tel (303)444-4149 ext.235
fax (303)444-4304
www.archenergy.com