Hello,

I am interesting in, if Houdini can be the right tool to create nebulae and galaxies that would look at least so good or better than on the links below.

Indeed, I am well aware that Houdini is capable of managing it. However, I have no clue how much work would be behind it, from installation of Houdini, learning it, and to creating a desired spiral gallaxy and Eagle nebula, I could later fly through.

Atm, I am XSI user. However, XSI lacks appropriate tools for creating below mentioned graphics. So I have two alternatives, to either move to Maya, that integrates very good set of particle tools, but to say ‘bye’ to XSI, or to stay with XSI and to learn Houdini as additional tool.

What solution would be more suitable, do you think?

Indeed, does Houdini contain some set of suitable shaders for such below mentioned effects? if no, is it difficult to program a shader that would do the job? Or is anywhere a huge database of shaders, I could chose, and modify to my needs?

The mentioned links are here:


http://www.physics.uc.edu/~hanson/ASTRO/LECTURENOTES/W04/Galaxy/M16WF2sm.jpg [physics.uc.edu]

http://www.ccastronomy.org/photo_tour_Nebula_Eagle_M16.jpg [ccastronomy.org]

http://data1.blog.de/blog/h/honigmonds-welt/img/Kopie-vonEagle-Nebula-M16-Pillar-Detail–Portion-of-Top.jpg [data1.blog.de]

http://www.geocities.com/SiliconValley/Lakes/1434/images/galaxyobjs.jpg [geocities.com]

http://www.geocities.com/SiliconValley/Lakes/1434/images/galaxysamp.jpg [geocities.com]

http://www.homestead.com/wysinger/files/galaxy.jpg [homestead.com]

http://upload.wikimedia.org/wikipedia/commons/c/c3/NGC_4414_%28NASA-med%29.jpg [upload.wikimedia.org]

http://starchild.gsfc.nasa.gov/Images/StarChild/universe_level2/ngc2997.gif [starchild.gsfc.nasa.gov]


Thanks and with regards,
Rene.

yeah, these links don't work.

Hello Jesta,

ah yeah, you are correct. I do aploogize. fixed broken links, and they should be Ok now.. Would you be so kind to look at them? I consided learning Houdni for this kind of work, but I dont know how difficult it will be. Atm, I am completely fluent in XSI.

With regards,
Rene.

What you want to acheive is well within the capability of Houdini.

You should look into I3D for perhaps doing lit nebula. Particles aren't neccessary, but you could use the to create the stars by spinning out a galaxy
and then creating a clouds using the particles.

YOu can also use a post process filter to add glows and sparklies to the particles to make them into stars.

Also don't under estimate painting textures and mapping them on geometry.
It's very effective and fast to render.

A combination of all or some of these will give you some pretty decent results.

good luck

Hello Jesta,

Thank you very much for reply.

Is I3D a feature of Houdini? Apparently from what I have heard, Houdini, should be the best software for creating such effects.

With Regards,
Rene.

And it is!

Check out the Advanced Renderman:Creating CGI for Motion Pictures book. It has a chapter written by Rob Bredow (Sony) and how they approached some f the parts of the opening shot to the movie Contact. One part focuses on approaches to render the Eagle nebula. Very clever stuff.
The opening shot for Contact was rendered in RenderMan but those same techniques can be easily applied to Mantra.

Star fields:
As well, Digital Domain used PRISMS to render realistic actual star fields for the correct date and time for Apollo13. Once again rendered in RenderMan and doable in mantra now. I believe that the stars weren't loaded in to PRISMS. PRISMS simiply supplied the correct transforms then passed the stars off to RenderMan directly as a read archive if I remember correctly.

Realistic star fields loaded in to Houdini consume quite a bit of memory hence the need for read archives off of disk. I have a realistic 80,000 star field (nearest and brightest stars to earth) with all kinds of attributes bound to them just to bloat the memory but can load and work with them in Houdini. Saw a re-run of Apollo13 a year ago and got inspired…
Lots of resources on the web to build your own realistic star system.

Don't cop out and do a random distribution of points. There's nothing like the real thing. :wink:

It's also fun choosing 1 houdini unit = 1 parsec. Yes units and precision are a constant issue.
http://en.wikipedia.org/wiki/Parsec [en.wikipedia.org]

Heya,

Heh. This topic has come up before… <cough> 10 years ago! <cough> :-)
A quick search of the mailing list reveals:
http://www.sidefx.com/index.php?option=com_mailarchive&Itemid=212&view=WEB&msgid=199602200704.SAA04165@redgate.vislab.usyd.edu.au&perpage=20&revdate=off [sidefx.com]

The Yale Bright Star Catalogue can be found via here:
http://tdc-www.harvard.edu/catalogs/bsc5.html [tdc-www.harvard.edu]

The Michael Jones' post (sgi performer) I referred to is here:
http://oss.sgi.com/projects/performer/mail/info-performer/perf-95-05/0167.html [oss.sgi.com]
It contains the 3010 brightest stars as viewed from earth, with Sol at (0,0,0)

keep in mind that stars differ in brightness… That helps significantly.. The next thing is to get a nice motion blur..

cheers,
ben.

Stars also differ in color.

I need to blow the dust off the old Astronomy books to see how to properly interpret the appropriate color field from the star databases.

Here's another web site from an enthusiast that has a database containing all stars brighter than magnitude +9.0, or closer than 50 parsecs.(87476 stars)

http://astronexus.com/node/34 [astronexus.com]

When searching for information on star fields, best to include the keywords Star Treck in your search string. Star Trek used real star fields as reference in all the TV shows including the original ones. It sure does seem like lots of Trekkies turned in to Astronomers…

Thank you both for valuable information.

The first thing, I should do si To create a realistic nebulae and galaxy shaders.

Jeff, yes, indeed, I have read Photorealistic RenderMan, and the chapter with explanation on how Contact shots were made. Indeed, this article brought me to the idea to start learing Houdini. :-)

Is shader development for Mantra a bit similar to shader development for Render Man?

I consider ordering and purchasing a book: Magic of Houdini. Have you read that book, and would you recomend it to me, to shorten the time necessary for learning Houdini?

Thank you and have a nice day,
Rene.

Bunkai
I consider ordering and purchasing a book: Magic of Houdini. Have you read that book, and would you recomend it to me, to shorten the time necessary for learning Houdini?

The Magic of Houdini was edited particularly well, wouldn't you say Jeff?

Bunkai
Is shader development for Mantra a bit similar to shader development for Render Man?

The concepts are essentially the same. The language, renderman sl vs mantra vex has it's syntax differences but they are minor. The shader structure is pretty much the same. Just search this forum and OdForce on vex. Also visit the OdForce wiki and Houdini's own in-line help on vex. VOPs offer a graphical way of building shaders with nodes. Makes it more pallatable to new users to programming their own shaders visually.

Bunkai
I consider ordering and purchasing a book: Magic of Houdini. Have you read that book, and would you recomend it to me, to shorten the time necessary for learning Houdini?

Yep. I was the Technical Writer. I scoured through all but one chapter of the book.
The book is friggin' amazing! An absolute must read for any aspiring Houdini user.

It will certainly give you the “why” along with the “how”. Houdini is all about why you do things the way you do. Not the paint-by-numbers approach. After absorbing the book, you start having technicolor dreams of different nodes in networks solving problems unimaginable in any other 3d software package.

Erm, or is that just me…

Hello Ben and Jeff,

Thank you both for recommendation. So when my new credit card arrives, I am going to order that book. At least it will be interesting reading but who knows…..

Because I am XSI user and I like XSI a lot, knowing how to programm shaders for MentalRay, that is essential renderer of XSI would help me to improve not only in Houdini with MRay but in XSI too. Do you think, this path would be acceptable and good choice for a XSI user?

I mean to decide for MentalRay to be the primary Houdini renderer, and then to utilize knowledge of MentalRay shader development to improve XSI skills.

Thanks and have a nice day,
Rene.