Alejandro Echeverry
Feb. 13, 2011 01:30:34
Hi!!
Test to drive smoke along a custom path.
http://vimeo.com/19882814 [
vimeo.com]
NFX
March 26, 2012 10:18:26
Hey Alejandro, I have been very impressed with all your work with the smoke sim. I have been using alot of your ideas to try and create a controllable cloud system for houdini and so am trying to understand how your node network works. While I have been able to implement my own particle driven curves into your network I have had some problems with some wierd smoke artifacts that are baffling me. Any chance you could look at my project file and see what I'm doing wrong?
VisualCortexLab
March 26, 2012 11:04:21
nice one, I really like the detail you get there. .. I'm trying to archieve a similar effect (except the smoke get sucked into a black hole where it disappears) … and I'd be very curious to know more about your setup

thanks!
Alejandro Echeverry
March 26, 2012 12:25:04
90ender
Hey Alejandro, I have been very impressed with all your work with the smoke sim. I have been using alot of your ideas to try and create a controllable cloud system for houdini and so am trying to understand how your node network works. While I have been able to implement my own particle driven curves into your network I have had some problems with some wierd smoke artifacts that are baffling me. Any chance you could look at my project file and see what I'm doing wrong?
Hi!!
The main problem here is that the curves deform at high speed, because of that the smoke doesn't follow well the path, you need to decrease the speed on the deformation or increase the number of sub-steps but it can be very very slow (ensure that your sop deformation has sub-steps).
Also if you have deformation in your path, don't use “set always” as default for all parameters only for “time” and “sop path”.
Alejandro Echeverry
March 26, 2012 12:30:25
sum][one
nice one, I really like the detail you get there. .. I'm trying to archieve a similar effect (except the smoke get sucked into a black hole where it disappears) … and I'd be very curious to know more about your setup 
thanks!
Thanks!!!
I'll upload soon the setup for H12, is more compact, better controls and very fast.
Cheers!!
NFX
March 29, 2012 16:17:58
Thanks for the advice. It made all the difference!
VisualCortexLab
March 30, 2012 06:06:16
alejandro
sum][one
nice one, I really like the detail you get there. .. I'm trying to archieve a similar effect (except the smoke get sucked into a black hole where it disappears) … and I'd be very curious to know more about your setup 
thanks!
Thanks!!!
I'll upload soon the setup for H12, is more compact, better controls and very fast.
Cheers!!
oh wow thanks, that would be very very appreciated

looking forward to it!
niietzshe
March 7, 2013 07:02:43
Did you ever finish the H12 version of this?
I'd love to have a look to see the differences.
Thank you for sharing so far, I have learnt a lot from this scene.
N
zdimaria
March 7, 2013 13:38:07
here is a version my buddy did in h12. worth checking out for sure.
http://www.usiak.com/velFromCurve.html [
usiak.com]
niietzshe
March 7, 2013 15:00:33
Thanks, checked it out and it's just a pump source sop, good, but Alejandro's has a lot of DOP stuff going on.
old_school
March 7, 2013 16:23:20
If you dive inside the Source Volume DOP (created by the Pump Shelf tool) and inspect the network inside you will similar things going on wrt creating ad hoc fields and populating them with the SOP's volume data including the ability to take in points (particles) and use these as Geometry data assigned to your Fluid object for further processing later.
Alejandro Echeverry
March 7, 2013 18:48:04
niietzshe
Did you ever finish the H12 version of this?
I'd love to have a look to see the differences.
Thank you for sharing so far, I have learnt a lot from this scene.
N
Here is the update for H12, also I haved use it to create this video
https://vimeo.com/60124045. [
vimeo.com]
The custom fields are all developed in SOP's, remember that you need to import into dops, and then mix it with the vel field, I used to normalize both, the vel field and the custom field, then add those directions, then add the magnitudes, then multiply each result (magnitudes, directions), all of this inside an if statement relative to the custom field magnitude threshold for better performance inside a gas field vop.
PD: Is not finish yet
Cheers!!!
angelia
March 13, 2013 23:16:48
Well done smoke!
niietzshe
March 14, 2013 07:18:50
Thanks for sharing!
Can you tell me why you normalise your velocities and add the magnitude back on later? Is it just to get a velocity bias so you can choose how much you want to add to it? I find it hard sometimes to control smoke without pushing it too far and stopping looking like smoke… Any tips?
Thanks
C
Alejandro Echeverry
March 14, 2013 10:54:08
niietzshe
Thanks for sharing!
Can you tell me why you normalise your velocities and add the magnitude back on later? Is it just to get a velocity bias so you can choose how much you want to add to it? I find it hard sometimes to control smoke without pushing it too far and stopping looking like smoke… Any tips?
Thanks
C
Because is the option that works for most test that I haved done recently, you have many options to mix your custom force with the main velocity: Add, Average, also with the default pump method with a final target velocity; But with direction only I can have always the smoke follow the custom force no matter if the custom force has a low magnitude, even though you need to test the custom magnitude relative to a threshold for the mix with the vel field, that way if the custom field is below the threshold the vel field is intact and flows as it should be.
fernansha
March 25, 2013 17:15:51
thanks for sharing this tool, alejandro..
I am just going through Your setup, as you mentioned we have to bring it into dops and mix it with vel,
can you pls post us a simple example or write it down in words, when ever is convenient for you.
coz i would like to learn from your setup, and learn then actual usage. i am kinda stuck how to actually proceed.
thank You.
maple
May 7, 2013 05:54:29
thanks for sharing this tool, alejandro
but i don't know how to use it. can you give me a project file,thanks very much
7pc
Sept. 6, 2014 16:17:19
Hi, I'm going to warm this up again.
I also seem to have problems getting the otl to work.
Any chance you integrate that into a hip?
Greeting and thanks!
Sadjad Rabiee
Sept. 18, 2014 11:46:17
alejandro
Hi!!
Test to drive smoke along a custom path.
http://vimeo.com/19882814 [vimeo.com]
Really good job Man :wink:
Alejandro Echeverry
Sept. 22, 2014 17:23:59
Joker386
alejandro
Hi!!
Test to drive smoke along a custom path.
http://vimeo.com/19882814 [vimeo.com]
Really good job Man :wink:
Thank you!!