“But, is it possible to do it only in one dopnet ? ”
Sure, I don't see why not. I prefer to split “sometimes” into different DOP networks if I know I can sim one differently than the other (Sometimes you require both at the same time). This way I can write the first DOP and then write the second. But this is really my personal way of working.

“How can fluid and smoke can interact with each other when we have two dopnet ?”
In this case, what's happening, Pyro is looking at the source for velocity. Since we have FLIP particles with the vel attribute, it will be taken as your initial velocity in DOPs… ain't that cool!! Now you can add the mesh of your FLIP as a collision obj for your smoke.

Again in that case it doesn't matter if you need one or 2 DOP networks… it's a matter of preferences I guess!

Too bad that glass doesn't emit smoke while melting… I'm sure it's extremely hot at that point!! lol…
You can always add a little smoke coming from the droplets or the liquid inside evaporating ??

Jeff's links are really interesting!! tempting me on melting some geometry!!

glad to help!

Hey Lewul,

It feels like your doing some lava if I'm correct!??

Here is a little scene that I set up for you quickly! there might be other ways to do it but this a simple one.

Hope it helps!!

ohhh!! This is not what you should see!
I'll report that as a bug since I got the same result.
But this is the way to go!

A quick fix, dive in your pyro shader (allow editing of the shader fisrt).
-you will see the on the top of your node tree the 4 export variables.
-add a parameter node and set the name to heat
-connect it to the export_fire_mask input!

This should get you the fire mask properly!
Thx

No problem!
You should always make sure that your geometry has a clean topology before you send it to DOP. Sometimes this can also affect simulation time is some cases!

Ok so I had a look at your file and it did crash the moment I added Make Breakable and played the sim.

But Looking closely at your Columns geometry I saw that there is some bad polygons… So I dived in your box_object1 and followed the steps and I noticed that your polycap node was not working well.

Since you polysplit and created Ngons (polygons with more than 4 points) the polycap was trying to cap the top edges with side edges.

Check the file, I added notes and added the Make Breakable and it works!

There is different ways to comp fire. Many compositors have their own ways.
Usually fire is not opaque. But if you want a mask or alpha, you can select the Red channel in comp ( quick fix ) … or….

If you look at the fire Shader in your shop networks, in Utils > Exports Tab you have a set of Variables that you can output in the Mantra plane.

As you can see you have the Fire Mask and Fire Color.

-In the mantra node, Properties > Output Tab add an Extra Image Plane.
-Set Vex Variable > fire_mask
-Set Vex Type > Float (It's written in the shader next to each variable)

Now when you render in ipr you can select the rendered planes individually. When you output an EXR, they will be all rendered in different channels but all in one file.

Hope it helps

Hi,
I just changed 2 values in your source and it might be what your looking for.

I added in the source node (in the POP network) some velocity in the Y axis and multiplied the Inherited velocity to a value of 6.

You had everything there to make it work, it was some little tweaking.

Hope it helps!

Have you tried it on a production build (Houdini 12.5.469) and see if it's still doing the same?

just out of curiosity can you send a file?

I'am sure that the best way to get a quick answer is post your questions in the forums. Houdini has a great responsive community and I've always found the replies you get are very helpful, not only to answer your questions but to understand more whats around it!

Tutorials gives you steps to achieve a particular setup but don't always get you informed about all the technicalities and why they proceeded that way!

Search the forum and if you can't find what you are looking for, post it !

looking good!!
If I may add those little notes about the dust smoke…
- I think you should add more turbulence & lower the swirl size. If I compare it to your reference.
- It should also dissipate slower and have the feel its a heavy dust smoke.
-last note would be the integration, make sure that your darkest blacks and your whitest white matches your plate. This helps you get at least the base color grading needed to make it integrate. Your bricks fits well with the plate but if you look at your dust smoke render, I feel the shadows are strong compared to the lit area or maybe its the inverse! a good way to adjust that would be to make a 3 point lighting (R-G-B) around your some where the blue for example would match your light, Green the shadow area and Red the camera view or back light. If you split them in comp, you can color correct each area of the smoke and have better control over the final look!

did I say it's looking good!!

Ok then send it as a Bug.

It's working fine with me too, but only tried it on Mint and Ubuntu.
What Houdini version are you using? try it on Houdini 12.5.427 if you haven't already. I'll check this out on Monday on a CentOS distro.

Never had an issue on Linux .
Can you describe more what are the errors and post a hip file? any screen grab would help too!

thx

Hi Lucas,
I set up a file for you!
hope it helps…

lari

Usually you would find “foam” where the surface tension of the water becomes really weak letting air settling in the surface!

This is caused mainly (but not only) by the agitation or velocity changes of the water. (Hope I still remember my physics and I'm not talking nonsense!)

If you look at water references ( Waves splashes, waterfalls, strong stream lakes or even water colliding on objects) you can see the natural effect of foam or white water… foam is a bit different since there is another natural component to it… maybe you want to google that part!

That's looking good!
Definitely White water (foam, and splashes) and wet map would have added much more details and realism!

Great work! Keep it up!

So I loaded your scene, and I see right away that you have the Multi, density and Temperature visualization checked… and I can see them properly!

Do you see the Temperature?


lari

No problem!
Both Bullet and RBD worked fine with me!
You should be able to make them both work as I mentioned in the notes!
Always visualize your collision mesh before you sim!
enjoy
lari

Hey hereacoon,
The first frames are fast because your sim starts at 35 when the RBD hits the ground. On my machine the first frame of Pyro (frame 35) takes a while to initialize but that's normal. Your Pyro container is huge, so at initialization (before the resize container kicks in) it has to create all the data for this box at every single voxel.

At frame 36, the resize container kicks in and the sim start running much faster.

What I would do! If your camera will show you the entire explosion(not cropped at the sides or the top) then it is worth to scale your container at the same size of your emitter (leave some padding) and in your resize_container > Max Bounds …
2 options …
first : uncheck the Clamp to Maximum, this will get your container to scale with the density until it dissipates. It can be very heavy at the end of your sim if you don't know when your density is dissipating.

second: keep it checked, set it to manual and define a big sized box and that will be the limit of pyro. ( I prefer that option!)

Now for the performance issue, can't tell why its not using all the CPU's, same on my machine but its not going slower from siming without writing to disk. If you have Allow caching to disk and you already played a couple of frames before it will write them down fast as bgeo. Else, it will sim every single frame.

lari

Hey Lewul,
I attached your scene with notes inside! every thing seem working goooood!
Its all about your collision objects when using Bullet….

hope it helps!