CGTalk > Sponsored Challenges and Awards > Past Challenges (Archives) > Eon (Model)
Login register
Thread Closed share thread « Previous Thread | Next Thread »
 
Thread Tools Search this Thread Display Modes
Old 06-29-2007, 06:43 PM   #76
digikris
Frequenter
portfolio
Harikrishnan Ponnurangam
Old Monk Productions LLC
Lakewood, USA
 
Join Date: Oct 2004
Posts: 173
Question

Hi Vikram,

I have more questions about Renderman Pro Server.

I'm not a student so i wont be able to get it for student rate. I have Maya 7 complete so it doesn't have Fluid dynamics. I'm thinking of going fro Vue Xstream integrate with Maya 7 to get water effects and generate a RIB file using Renderman Studio and Render it in RPS. I'm not going for Embeded Renderer in RMS its a separate license and works on Maya memory foot print. Do you think Vue Xstream - Maya 7 complete - RMS -RPS workflow will work. Becuase Maya 7 doesn't have fluid dynamics but tonight i will be trying it out.

Tell me about RMS and RPS shaders towards dynamics.

Hari
 
Old 06-29-2007, 07:27 PM   #77
vmulligan
Know-it-All
 
vmulligan's Avatar
portfolio
Vikram Mulligan
Postdoctoral researcher
University of Washington
Seattle, United%2BStates
 
Join Date: Nov 2006
Posts: 355
Hi, Hari:

Before answering your questions, I should put a little disclaimer here: I've never used Renderman Pro Server. All my experience with Renderman-compliant renderers has been with the freeware or shareware clones (3Delight, Aqsis, Pixie, and BMRT). I've also only played around a bit with the Personal Learning Edition of Vue XStream, so I'm not really a Vue expert.

What kinds of water effects are you trying to create? Do you want to make ponds, streams, and oceans, or are you more interested with flowing, splashing water (e.g. water pouring from a bottle into a glass)? If the former, Vue 6 XStream itself seems to be a pretty good solution, from what I've seen of it. Trying to integrate Vue 6 with Renderman might be a bit tricky, though. Vue 6 is a renderer unto itself, and the XStream plugin is made for automatically compositing material rendered in Vue 6 with material rendered in Maya's renderer or in Mental Ray. I don't think XStream really speaks the same language as Renderman. If I were you, I'd EITHER go with Vue 6, OR use Renderman. The advantage of the former is that it makes landscape and seascape creation very automatic, while the latter's advantage is that it gives you absolute control over pixel-level computation. You'll probably have a fair bit of manual tweaking to do if you want to integrate them, though.

Still, if you can try it without losing money, go for it; I could be wrong. The free Personal Learning Edition of Vue 6 can give you an idea as to whether you can do it; its images are watermarked, but it's otherwise fully functional. You could also try the freeware Liquid Maya to Renderman plugin and a freeware or shareware Renderman-compliant renderer like 3delight or Aqsis. (To clarify, the name of the plugin is Liquid; it's not made just for liquid effects or anything like that). I don't know what your financial or time constraints are, but this would give you a way to test your proposed workflow using what you have and software you can download for free.

All of the above applies to rendering large bodies of water (lakes, rivers, oceans, etc.). If you want to make splashing water droplets, I'd recommend looking into Realflow 4 or a related fluid dynamics simulator. As I understand it, Realflow generates animated liquid meshes that can then be rendered in any renderer. Incidentally, ray-tracing was only added to Pixar's Renderman recently, so it might not be the very best renderer to use if you want ray-traced water effects. You might want to stick with Mental Ray for that. I can't say for certain, though, having never used Pixar's Renderman.

I hope this helps. The only other advice I have is that you ask around. My experience is limited, and it's always a good idea to get a second opinion.

Best regards,

--Vikram
__________________
B-Movie.
Steampunk.
Uplift Universe.
Strange Behaviour animation and still.
Eon animation and still.

Last edited by vmulligan : 06-29-2007 at 07:30 PM.
 
Old 06-29-2007, 07:53 PM   #78
vmulligan
Know-it-All
 
vmulligan's Avatar
portfolio
Vikram Mulligan
Postdoctoral researcher
University of Washington
Seattle, United%2BStates
 
Join Date: Nov 2006
Posts: 355
Quote:
Originally Posted by digikris
Tell me about RMS and RPS shaders towards dynamics.


I missed the last line .

Renderman shaders can do whatever you can code. If you can write a decent water shader, you can generate photoreal water. It's not an automatic thing, though -- you need to write whatever shader you use. With most Renderman-compliant renderers, there are default shaders, but they tend to be pretty bare-bones (constant matte, plastic/phong, etc.).
__________________
B-Movie.
Steampunk.
Uplift Universe.
Strange Behaviour animation and still.
Eon animation and still.
 
Old 06-29-2007, 10:13 PM   #79
digikris
Frequenter
portfolio
Harikrishnan Ponnurangam
Old Monk Productions LLC
Lakewood, USA
 
Join Date: Oct 2004
Posts: 173
Thanks for the insight.

I need both. splashing water as well as ponds, lakes and oceans. I have vue 6 infinite its really awesome for those effects. But not for animated fluids. Like beer flowing out of a bottle or a soda can. Exactly need Ray tracing too.

Real Flow was a good suggestion. I also tried blender for fluids. But i have to learn the interface. Most of the time i'm wasting on the interface. I would be glad if Blender had a Maya interface presets like vue.

Renderman Pro server: Do you mean i can write realistic animated water shaders? Like beer flowing out of a bottle and stuff.

Thanks,
Hari
 
Old 07-03-2007, 05:26 AM   #80
vmulligan
Know-it-All
 
vmulligan's Avatar
portfolio
Vikram Mulligan
Postdoctoral researcher
University of Washington
Seattle, United%2BStates
 
Join Date: Nov 2006
Posts: 355
Quote:
Originally Posted by digikris

Real Flow was a good suggestion. I also tried blender for fluids. But i have to learn the interface. Most of the time i'm wasting on the interface. I would be glad if Blender had a Maya interface presets like vue.

Renderman Pro server: Do you mean i can write realistic animated water shaders? Like beer flowing out of a bottle and stuff.



Yeah, I've played around a bit with Blender. It's an amazingly powerful freeware program, but immensely difficult to learn. I agree that the interface needs work. Still, some people swear by it. If you can learn it, it may be the solution for you.

You can certainly write realistic Renderman shaders for flowing beer. In Renderman, there are five shader types: light shaders (which define how you scene lights work -- e.g. point light, spot light, etc.), volume shaders (which are used for effects like fog or underwater silt), surface shaders (which tell the renderer how light interacts with a surface to give it its colour), displacement shaders (which define small bumps on the surface of an object), and imager shaders (which tell the renderer what to do with the final 2D rendered image to tweak it -- e.g. to add film grain, or to adjust the exposure). Unlike Mental Ray shaders, Renderman shaders can't create new geometry. They can only modify existing geometry. (Actually, this isn't 100% true. Advanced Renderman users will tell you that there are ways of using surface or volume shaders to create isosurfaces from 3D volumetric density functions, but this would be a very difficult way to generate flowing beer.)

Assuming you've already created the mesh for your flowing beer (e.g. as a Maya particle effect, or using Realflow), you can create a surface shader to give the beer its golden colour, shininess, and transparency (complete with ray-traced refractions and reflections, depending on the particular Renderman-compliant renderer you're using). You could use a volume shader to add little bubbles inside the beer, and a displacement shader to add foam to the beer's surface.

If you look at the first post in this thread, you'll see an example Renderman shader I wrote to make the hexagonal pattern on the walls of the borehole. The syntax is like C++, and is very easy to learn if you have any programming background at all. This is a surface shader, as it affects the colour and the specular properties of the surface. I also used a displacement shader to raise the edges of the hexagons.

For more information on writing Renderman shaders, here are some useful links and books:

The Renderman Academy.
http://www.rendermanacademy.com/

Advanced Renderman: Creating CGI for Motion Pictures, by Anthony Apodaca and Larry Gritz. (1999).
http://www.amazon.com/Advanced-RenderMan-Creating-Pictures-Kaufmann/dp/1558606181

Essential RenderMan, by Ian Stephenson. (2007).
http://www.springer.com/west/home/g...-22-131388437-0
(Note that I'm a bit biased, since I did one illustration for this book).
__________________
B-Movie.
Steampunk.
Uplift Universe.
Strange Behaviour animation and still.
Eon animation and still.
 
Old 07-03-2007, 05:26 AM   #81
CGTalk Moderation
Expert
CGTalk Forum Leader
 
Join Date: Sep 2003
Posts: 1,066,478
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
__________________
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
 
Thread Closed share thread


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 05:48 AM.


Powered by vBulletin
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.