Phoenix texmap

[9k_JHT]

Well let's see what Svetlin comes back with. This should be a fairly straightforward thing for the user to do. I very well could be doing something incorrect here on my end too. I hate to say it, but there is always the possibility that this might be a bug or a oversight as well.

What's frustrating is that the information is 100% there in the preview of the viewport, but I still don't know why there would be such a variation in temperature information for a fluid/liquid sim that has no heat source. Fingers crossed that there is a way I can apply this blending of materials to the simulation I've been running for the past week. Using a Maya solver that must be one of the single threaded ones discussed in the documentation.

Go Svetlin! Go Svetlin!

[ivaylo.ivanov]

You must use the Phoenix FD texture to sample the temperature, and then remap it to values between 0 and 1.

[9k_JHT]

You must use the Phoenix FD texture to sample the temperature, and then remap it to values between 0 and 1.

So I hear....

I create a Phoenix Sim with a temp channel. Create a PhoenixFDTexture pointing it to the sim's temp channel, apply the phoenixFDTexture to the simulation, change the generic generated texture that is created to anything (for simplistic example let's say a VrayMTL with the out color of the PhoenixFDTexture pumped into the diffuse). I get, absolute black because the out color of the PhoenixFDTexuture is completely zero'd.

So, I figure that there perhaps is something special going on since the default temp values range from 300-2000 and RGB goes from 0-255 standard... So I create the appropriate math logic as suggested below and plugged it into the VrayMTL and insta-Crash. That's because (for whatever reason), the PhoenixFDTex Temp channel is zero'd and not giving any data.

This is the same for the velocity channel (which was also exported during the simulation).

Either I'm missing something very huge or there is something very wrong with the PhoenixFDTexture/Temp channel. Followed Svetlin's instructions which resulted in a crash of Maya. So, please feel free to download the sample scene I posted below via weTransfer and try your hand at getting the appropriate results. If you could show me a working example with the demo scene I posted then I can see how this this is done.

Let me know if I need to upload the scene again.

As of now I'm following the instructions given to me and not getting anywhere.

Best,
Clayton

[Svetlin.Nikolov]

Hey,

Sorry for too many replies and too little reading So I mentioned it in the other thread regarding the liquid sim crash, but this crash here is in V-Ray and I don't think the fix will come in for tomorrow. I will try to setup your scene to workaround the crash and get it back to you this eve, so you can try with tomorrow's Phoenix nightly.

Cheers!

[9k_JHT]

Hey,

Sorry for too many replies and too little reading So I mentioned it in the other thread regarding the liquid sim crash, but this crash here is in V-Ray and I don't think the fix will come in for tomorrow. I will try to setup your scene to workaround the crash and get it back to you this eve, so you can try with tomorrow's Phoenix nightly.

Cheers!

Thank you for the response.

Awesome. Let me know how it goes! I'm excited to see what you can come up with.

[Svetlin.Nikolov]

Alright, so more progress on the saga - apart from the V-Ray crash which you can avoid by using the remapColor node as Ivaylo Ivanov pointed out, there are indeed issues with the PhoenixFDTexture reading the temperature and the velocity channels, so this will need some fixing and will hopefully be in for 03 Mar.

Apart from that, I've checked to make sure the Phoenix texture outputs the values as they are in the grid, so no need to worry about standard 0-255 range issues.

In your scene the temperature channel is in a range between 0 and about 1.5, so for this exact setup in the remapColor you need to set Input Min to 0, Input Max to 1.5, and keep the outputs in 0-1. Another thing you already asked is that the temperature channel does not represent liquid temperature - it's a legacy thing from the fire/smoke core that if you simulate liquids, the temperature channel is reused for the liquids and it in fact represents liquid density. It usually is in 0-1 or thereabout already. We'll remove this legacy completely as soon as we can, but for now we should at least rename 'Temperature' to 'Temperature/Liquid' as it is in 3ds max.

Another thing I should point out is that since you are using the liquid/temperature channel as the render surface (you can choose which channel is the surface from the Rendering panel), then if you use temperature for the color too, the entire surface will always have the same color, because the surface is built over all parts of the liquid with the same density. You could instead use the velocity to map materials over the liquid, but this depends on the effect you are after.

Attached you can find the modified setup after the fixes to the Phoenix texture along with a simple render with the velocity channel used as blend factor between the blue and red materials. It will not work with tomorrow's nightly (02 Mar) but the fixes will be in for 03 Mar I hope.

Note that the velocity is in range from 0 to about 500-600, but the Phoenix texture exports it as a vector for 3D displacement, so it has the directions coded in the color and the color components may be negative. This is why I've run it through a multiplication by itself to get rid of negative values, and so the Input Max on the remapColor is 200K, which is a little less than the squared max velocity. Together with the fixes, I'll add another channel to the Phoenix texture with the scalar Speed which will not be a 3D vector, but a simple monochrome color. Then you won't have to do such tricks and Input Max can be around 500.

I'll update you when the fixes are in the Phoenix nightlies. Cheers!

pDemoScene_modified.zip

[9k_JHT]

Good news and bad.

Good news is that it works. Bad news is that it is only working for one frame. When I scrub the timeline it hiccups back to a single material.

https://youtu.be/IA5dpScL_m4

I'm using the velocity to drive the texture and the liquid/temp to drive the surface as you suggested. The results are prefect besides this bump in the road which makes it completely useless for production. Hopefully it can be fixed soon in a nightly release.

Thank you for your help Svetlin. Please keep me posted on when this particular issue might be fixed. Once again, if you think I could be doing something wrong on my end, let me know. This is out of the demo scene you sent back to me.

@ivaylo - Thank you for the recommendation. I did not understand that you were referring to a remap node. A remap node makes 100% more sense in this situation then what I was attempting to do with the math nodes.

[Svetlin.Nikolov]

Yup, this is how it works before the fix - it will be in for tomorrow (03 March)

[Svetlin.Nikolov]

Okay, the fixes are in - I didn't manage to add a separate Speed channel to the Phoenix texture - hope this will be in the nightlies in а couple of days too. Cheers!

[9k_JHT]

Okay, the fixes are in - I didn't manage to add a separate Speed channel to the Phoenix texture - hope this will be in the nightlies in а couple of days too. Cheers!

You and the team are surely a bunch of wizards. Thank you so much. Very excited to start developing some material applications for my current project. This is going to work out perfect.

[Svetlin.Nikolov]

Hehe, good luck! If possible, please share when it's done .. or bump us if you find anything wrong

[Svetlin.Nikolov]

Hey - just an update - for tomorrow's nightly (08 March) there will also be a scalar Speed channel for the Phoenix Texture in both Max and Maya, so there won't be the need for such math hacks as in the scene we exchanged previously, and thus in the remapColor's Input Max you would be able to use the actual max speed.

Cheers!

[9k_JHT]

Woooo! Sounds awesome. Quick question. Does Chaosgroup offer any simulation render farm services for Phoenix? I'm on the hunt as we've been simulating for the past week and 2 days with a Maya field solver that is single threaded as all hell.

I'm looking for options to get this done quicker. Do you offer any leasing of Phoenix sim nodes or a sim farm service? Thanks!

[flipbook]

Does this mean we don't have to create a dummy Fire grid and load the Liquid cache and use speed as opacity for 3ds max? Maybe I've been doing it old school way and there is a new method since the core was split into two.

Just tried it using a dummy Liquid sim, setting the PhoenixTexture map to use Speed. Getting a correct speed map but the blend just goes mental

https://www.dropbox.com/s/tamlyhxos6...d_map.JPG?dl=0

* Looks like its a seperate issue, started a new thread

** Ignore me, works fine! Forgot to set frozen dummy grid to non-renderable!

[Svetlin.Nikolov]

Hey guys,

@Clayton - no distributed sim for now, sorry - although I'm not sure if this is actually what you need - why do you use the Maya field solver in the first place?

@flipbook - I was thinking of removing the node connector from the 3ds max Phoenix Texture and replacing it with a text field as in Maya. We can pop a node selector window so you won't have to wonder how your sim was named. This way there won't be a circular reference error when using the Phoenix Texture and there won't be the need for a dummy simulator at all, which is a pretty crappy experience IMO. Of course we'll have to handle node rename and scene merge, but it's not a big pain compared to the current way. And I'll see if we can pop a node selector in Maya as well, for that matter.

Cheers!