Zoic Wishlist

[Rchapin]

Hey guys, on the front lines of production on at least a dozen TV shows, here are a few items we'd like to add to whatever list is floating around. We're currently using the 2.0 Maya plugin. I also work as a VFX sup for a few other studios and I'd like to be able to recommend Phoenix if asked which FD system to use.

1. Better documentation. In particular, listing exactly what each button does in better detail with a quick example.
2. Tutorials. Step by step procedures for achieving advanced techniques - like cascading sims or particle texture.
3. Various bug fixes listed in this post: http://www.chaosgroup.com/forums/vbu...uction-buglist
Right now, we're dealing with an issue where a sim will completely disappear from the viewport depending on the distance and angle from the camera. Nothing helps including adjusting clipping planes.
4. Allow Maya fields to drive Phoenix sims with predictable results. Most fields completely blow away any sim.
5. Allow Phoenix per-particle attributes like lifespan and Color. Allow Maya particles to emit colors into fluid.
6. Allow emission of fluid from geometry texture without colliding with the geometry. Currently, listing the geometry in the scene interaction kills any texture emission and/or normal direction.
7. Correct motion blur for smoke/fire - even if it's a subsampling solution. Anything.
8. Better support. Really glad Ivaylo is here, but just one person doesn't seem like enough to support the entire community which is working on major projects all over the world with crazy deadlines. I've been in the biz for 20 years and I'm hoping Phoenix will be around for a while. It has great potential, but I've noticed that one of the major factors of software longevity is customer support.

Bob

[ivaylo.ivanov]

Thanks for the feedback.
Better documentation is always needed. The current idea is to have introduction section that must explain in depth how Phoenix works and shorter sections which explain the individual options. I'm not sure if more information on per attribute/button basis will work, probably we can group them in sections that elaborate more on some particular topic.
The lack of tutorials is probably the biggest problem. Currently we have this small section http://www.spot3d.com/phoenix_maya_20/quick.htm. If it works for the users, new topics can always be added.

The situation with fields is not easy, since we only get from Maya the final result. We can only improve the compatibility and somewhat the performance. If you have problems, the best way is to send us a scene. There is an idea to implement our own fields which can work better with Phoenix.

Per particle attributes can be used via particleSamplerInfo. Check out the phx_pfsource example.

About 6, I was trying to explain in the previous post that it's working, but you need to use 3d texture. When the body do not interact with the simulator, it emits from its whole volume. Do you need to use 2d textures?

We are two Ivaylos

[Ivaylo Katev]

thanks for the feedback bob!
some of the problems we already know, and we are working on the solutions.
could you clarify point 6? the sources in phoenix affect the entire volume when the object is not interacting with the simulation. your suggestion is to keep them to affect the surface only as i understand?

[Rchapin]

Thanks for getting back to us Ivaylo. And thanks for the link to spot3d - wish I had that when I had 2 days to get up to speed on Phoenix. Where is this guide listed so people might be able to find it easier?

Re: Maya fields - Compatibility and performance are what we're hoping for, which is why it's on a wishlist. Right now, we're dealing with a lot of magical smoke which has to flow in very specific directions. None of our Maya fields seem to work and our best bet has been to emit from particles which flow along the fields. The downside to this is that the smoke isn't being pulled in a certain direction, it's being emitted in a certain direction, which isn't exactly the look we're going for (wispy tendrils).

Re: Particles - I was referring to the particles emitted from a Phoenix source. I don't believe there's anything to control their per-particle attributes such as opacity and lifespan. And I didn't see a particleSampler node used in the pfsource example.

Re: Geometry Texture - It would be nice to have geometry emit from a 2D texture if the geometry is hidden (excluded in scene interaction), which is why it's on a wishlist. This became a big problem during production when we needed this functionality. I didn't realize that hiding the geometry would suddenly emit from the entire geometry - kill 2d texture emission as well as normal discharge direction.

For example, you have a texture on a large plane that you would like to emit smoke, the plane is translated around the volume, but you don't want the plane to swirl the contents of the volume, you just want it as an emitter. And you don't want the entire plane to emit smoke, just the texture.

And to show the problem with discharge direction, simply emit fire from a plane turned sideways. Then exclude it from scene interaction.

[Ivaylo Katev]

about the fields: the commonly accepted way to force the smoke to follow path is to use particles. the regular fluids always give bad results, because they do not obey the pressure resistance, and tend to form areas with higher pressure that opposes to their efforts. the particles method produces better results, but the smoke tends to accumulate, i would suggest to use negative source particles to remove the extra smoke. actually a technique for smoke guiding is widely needed, so it will be included in the planned tutorials.

about the 2d sources - the plane example is clear enough, we will consider how to solve the problem. phoenix is initially designed for 3dmax, where is no difference between 2d and 3d textures, and perhaps this is the reason skip this feature.

[ivaylo.ivanov]

The guide is at the bottom of the official help http://www.spot3d.com/phoenix_maya_20/.

True, the particles emitted from Phoenix itself are very simple. PhoenixFD Force Field can be used to guide Maya particles in a similar way, but they will be much slower. It's true that there isn't any middle ground solution.

[Zach Gray]

I'm building off of the fine smoke example to make a supernatural contrail, but I'd like to add a lifespan to the particles to show dissipation. Is this possible?

From reading above, perhaps not?

[Ivaylo Katev]

actually we have lifespan, perhaps is not added in the maya UI.
in this case you can use foam particles with very low falling limit, they will act like simple particles dragged by the air.

[Zach Gray]

Using 2.00 x64. listAttr on the PhoenixFDSource doesn't report lifespan. Enabling foam doesn't seem to have an effect with the phx_finesmoke example which has fluid discharge particles. Am I misunderstanding the approach? The finesmoke example looks perfect aside from the fact that the particles over accumulate.

[Ivaylo Katev]

you have to replace the type of the particles in the source, in the finesmoke they are drag particles, you have to make them foam. this will allow you to adjust the lifespan by the halflife parameter of the foam. keep in mind that the liquids must be enabled, otherwise phoenix will ignore the foam particles. and you have to change the b2b interaction of the foam to zero, otherwise the foam particles will stick to each other.

[Zach Gray]

Thanks. I got that setup, but now the issue is that the liquid required for the foam emission continuously emits foam. I've got the half life for the foam set to .01 and they don't seem to die. I also tried the 'make particle system' checkbox to make the particles into nParticles, but the 'Lifespan' attr doesn't exist on the nParticle shape.

[Ivaylo Katev]

not sure that understand the situation fully.
can you attach some preview video?

[ivaylo.ivanov]

If you use nParticle system, the lifespan is not implemented in this version. The only way to go with them is animate the opacity. The full lifespan support is in the nightlies, but I can't recommend them yet for important work...

[Zach Gray]

I'm away for a few days, but I'll get an example when I get back.