Archived post by aswaab

@Nick D with the built in houdini stuff, if you want to preserve fluid sheets, you have a couple methods… 1. Abuse particle reseeding + substepping. Increase the surface oversampling significantly. This will add a lot more particles around the narrow surface bandwidth (you can increase this to 2 if you want, also), which will help preserve sheets.
2. Use a LOT more particles, shoved into the same space and use particle separation (Need to disable reseeding, or else you will get uncontrollable volume gain). On the flip source, you can override the oversampling parameter to force more particles to be generated. This can be pretty helpful. If this method works for you, you should get a pretty clean flicker-free mesh, as you are not doing reseeding.

Reseeding + particle separation is generally not recommended, as you do get very noticeable and uncontrollable volume gain. These two things kind of work opposite to each other.

The problem with both the reseeding options (both my version and the built in one) is that once you start preserving fluid sheets it becomes hard to get them to break up naturally. I’m still working on some ideas for that.

In general, for small scale fluid fx, I prefer lots of particles + particle separation. A little viscosity can help smooth out the neighboring particles to reduce their separation from velocity effects.

Archived post by petz

hey jake, my little rant wasn’t directed to you. sorry if it came off that way! it was just me having a moment of bad temper.

anyways, i’m just putting together a quick fix of your file. i’ll upload it in a minute …

here’s the file.

it’s sparsely/not commented but should do the trick. on the right there is div-free field coming from DOPS to compare against the result …

Attachments in this post:
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20195404/24/19/poisson1.hiplc

Archived post by jake rice

lemme hook u up with one that works with edits

1 sec

no need for any transformation attributes unless you want to do vector volumes with this technique 😃

this one is all inspired from an old convo in here with tjeeds and matte 😮 😮

you don’t necessarily need to activate a new volume, like you could do this on the original volume, but just know that the bounds will most likely need to be updated to match the deformation tet mesh

Attachments in this post:
http://fx-td.com/houdiniandchill/wp-content/uploads/discord/20191504/24/19/jr_non_poopy_vol_deform.hip

Archived post by Bender

you can save them

“Just to expand on the regular presets facility… If you create a bunch of presets for your digital asset, you’ll end up with a file called $HH/presets/Object/myasset.idx, or something similar. This is the file that contains all the preset definitions you have saved. Find this file and remember where it is. Now open the Operator Type Manager and find the definition of your asset. Right-click on it and choose “Edit Contents…”. On the left is a list of “sections” that make up your digital asset definition. Below that list is a spot to enter the name of a file. Use the Plus button to open up a file browser and find the .idx file containing your presets. The “Section Name” will be set to the name of the .idx file. Change the Section Name to “Presets”. Hit the Add File button. Hit Accept. Now those presets are stored with the digital asset.
This ability to store presets directly in a digital asset definition isn’t well advertised because it is far from being an automatic process. Updating that Presets section requires saving it out to the .idx file, adding or editing the presets in that external file, then re-adding the .idx file using the Edit Contents dialog. It’s not pretty, but it can be a very useful feature. “

www.sidefx.com/forum/topic/3449/?page=1#post-254885

Archived post by bonsak

Sample rate in chops is not always tied to the frames pr second you operate in. If you are sampling audio for example you might want higher sample rates. But i agree it could at least be $FPS. I put this in my houdini.env: “`FPS = 25 HOUDINI_CHOP_UNITS = frames“` This sets FPS in your hip to 25(i dont do any film work), sets Sample Rate in chops to 25 and Unit in chops to Frames. I always mess up when its set to Seconds(default)