We're all excited about Houdini's new RBD and Fluid solver, not to mention full softbody support for cloth. Does anybody know anything about the capabilities of these new DOP operators?

Can rigid bodies work on groups of objects? If I had 100 spheres copy/stamped to a grid, could I make all those spheres seperate rigid bodies?

Will fluids work similarly to RealFlow? Is there a difference in speed? Faster, slower as far as in how much time it takes to go through the calculations?

Can fluids interract with softbodies and/or rigid bodies? Could I pour fluid particles into a container with a “cloth” stretched within the container and have the falling liquid move the softbody “tarp”? If there was some elasticity to the softbody tarp, would it fling fluid particles back up into the air after “bouncing” off the tarp?

Will new shaders be released to compliment the new fluids?

Will we be able to use the fluid solver to create clouds and gasses like in Maya Fluids?

So many questions…

:?: :?: :?:

Hiya,

While I can't answer your questions, I thought I might chime in a little bit.


Houdini's DOP system has definitely generated quite a bit of buzz around the community and we are all definitely looking forward to it. For big studios, it will be awesome as this allows them to plug their own specific dynamic solvers to Houdini and have it all interact with one another. So this might means having your RBD interact with cloth and may be fluid:?:. From one of the conversation I have with an exMaya guy here, he mentioned to me that Maya's Fluid dynamics is actually a MEL hack for the most part. For things as complex as what you've seen on Digital Domain's CFD on DAY AFTER TOMORROW, Maya's CFD will not hold. Anyways, don't quote me for any of that as I am not working at SESI to know truely what's going on.

Regardless of whether or not you have the fluid solver, you can render your volumetric effects just from the particles for the most part. So, for now, you can even use your RealFlow to generate the fluid particles and import it into Houdini to render.

I personally would be interested in knowing how VEX will handle DOP stuff. I have just dove into the VEX SOP world fairly recently. It's pretty fun.

It'll be good.
-A

I'm fairly certain that fluids will not make it into the DOPs for the next version.

Although, you never know . Personally I'll be happy with the RBD and Cloth (oh, and hair ).

M

Yeah, RBD, hair and cloth are good enough for me for the time being.

But sadly, I have not done much character and modeling stuff for a long time now… :cry: I remember how back then I keep on wanting to be able to do hair and cloth as I DON'T want to have a bald character with either skin-tight or no clothe at all. I guess may be I should start learning more of Houdini's Character Tools again… Now that I got some furniture in my apartment.

Yeah I'd be happy with rbd and cloth. Although I've been able to fake both quite nicely with the toolset we have now. Same with hair.

I suspected Maya Fluids was more or less just a huge Mel script running piggy backed on the rest of Maya. After having learned it myself that was the impression I got. Infact, I've built some setups in Houdini that more or less do the same thing (minus the actual fluid solver.) Fluids is fun until you reach its limits – which doesnt take too long. Nevertheless it can be a life saver in certain situations, which is why I cant wait to get my hands on something similar (and I'm hoping much, much better) in Houdini.

The place I worked before this was a big Maya house and they called Maya fluids the “silver bullet of effects animation.” I laughed at that title, afterall, I doubt Maya Fluids could create a silver bullet effect

the_squid
The place I worked before this was a big Maya house and they called Maya fluids the “silver bullet of effects animation.”

'cos it was easy to shoot yourself in the foot with it…

Man if that is not the truth. Maya Fluids = long render times. lol

I missed the meeting sorry all. So they have fluids too huh. Wow. Well then now it appears they have everything. Now it will be down to pickyness. lol Which is a very good thing indeed.

Cheers,
Nate Nesler

hey all

yeah mayas fluids should only really be used for cell phone logos, unless u have a large 80x40 screen, then u gotta buy a render farm

about the fluids in houdini 8, it was mentioned that level sets but by their other name, Signed Distance Field, will be released on H8 at http://odforce.net/forum/index.php?showtopic=2340 [odforce.net]

any new bout when H8 is gonna be a beta?

aracid

Hi, i would recommend you something - instead of blaming Maya's tools, to find a computer with installed Unlimited version and to take a look what exactly is going on there.

If you give it a try i think that in most cases you will notice that the fluid solver is very well implemented in Maya and cooperates with the rest of the stuff really nicely. It is not a closed system.

In addition to the regular fluid simulations you can do and things like that:

FluidContainers can be used as force fields for particles, rigid bodies, softBodies, cloth, hair/dynamicCurves, paintFX strokes, etc., or to be affected by most of them.
Fluids can be used to texture geometry ( every geoShape intersecting fluid can be colored, or directly textureMapped via HyperShade ).
You can substitute the particleCloudShader with Fluids and you can control them on perParticle basis ( pretty mutch like AfterBurn for 3DS MAX or HyperVoxels for LW3D ).
Using MEL you have perVoxel control over the fluidContainer - you can query and control every single voxel cell.

Also, there are 2 other types of fluids - oceanShader and pond. The ocean shader is really neat stuff - can be affected by particles or whatever to create effects like ripples, wakes, etc. Also the same can be done using fluidContrainers ( exploding fluid can affect the ocean surface - just an example ). In fact the oceanShader can interact with almost everything containging UV-data and shaders.

The pond is some kind of fluid + springs - very interesting beast.

The rendering of fluids is really fast - if you know what are you doing you can have almost realtime rendering of your fluids ( here i mean only gas and clouds stuff, the ocean shader is far from any realtime rendering ). Somehow MentalRay renders them faster than Maya Software Renderer.
And last - the rendering quality is really great.

About the MEL hacks - i really would be glad to have more MEL control ( hacks ) over the fluids, now they are pretty mutch only compiled code and i really dont like that.

When we talk about MEL hacks - good one is the ability to use bitmaps to control your fluids - colors, velocity, density, etc.

I know that my post will not be well accepted here, but i have the feeling that many people are missing the essence of this Maya tool. Why that please accept my words like little heads-up, not as offense.