Yeah, actually that's what I ended up doing (I'm experimenting with the fastest way of merging particle wedges). I don't know if that's multithreaded, though. But anyway, it's pretty handy!
cheers
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Technical Discussion » compiled-block version of File Merge SOP?
- riviera
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Technical Discussion » compiled-block version of File Merge SOP?
- riviera
- 1694 posts
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Hey,
I'm just wondering if it is possible to do a compile-block variant of something like the File Merge SOP – and more importantly, would it result in multi-threaded reading of the slice files? (e.g. each thread would load a single slice/wedge, but in parallel)
cheers
Imre
I'm just wondering if it is possible to do a compile-block variant of something like the File Merge SOP – and more importantly, would it result in multi-threaded reading of the slice files? (e.g. each thread would load a single slice/wedge, but in parallel)
cheers
Imre
3rd Party » qLib - an open source asset library for Houdini
- riviera
- 1694 posts
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bonsakrivieraOps didn't read the wiki. Thanks.
- yes, place it in the experimental folder (but the process is described in the wiki)rivieraPull request
- what's PR?
-b
ah okay dev branch is fine, I'd think…
3rd Party » qLib - an open source asset library for Houdini
- riviera
- 1694 posts
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bonsak
Hi.
Great initiative!
If i want to contribute, i fork the dev branch and:
- If i make a new otl do i place it in the experimental folder? Or how do you want this organised?
- Do you want PR's in the dev branch or in separate pr issue branches?
Hi Bonsak,
- yes, place it in the experimental folder (but the process is described in the wiki)
- what's PR?
cheers
ps.: Yes, hda help seems to be broken for now in Houdini, too bad
Technical Discussion » how to determine if volume primitive is 16-bit?
- riviera
- 1694 posts
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My question was about regular (non-VDB) volumes, VDBs are (afaik) always stored as floats in memory.
Thanks for the workaround suggestions. The workaround I usually go for (with mixed success, I might add) is to toggle the 16bit switch on a Volume Compress SOP and see how the memory consumption changes. Bit awkward, though.
Thanks for the workaround suggestions. The workaround I usually go for (with mixed success, I might add) is to toggle the 16bit switch on a Volume Compress SOP and see how the memory consumption changes. Bit awkward, though.
Technical Discussion » how to determine if volume primitive is 16-bit?
- riviera
- 1694 posts
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Hi,
What's the simplest way of detecting if a (regular) volume primitive stored in 16-bit representation in memory? (I just need for manual instpection, “Extended Info”-kind of thing, although any script command would also do. )
cheers,
Imre
What's the simplest way of detecting if a (regular) volume primitive stored in 16-bit representation in memory? (I just need for manual instpection, “Extended Info”-kind of thing, although any script command would also do. )
cheers,
Imre
Technical Discussion » Segmentation Fault - Crash
- riviera
- 1694 posts
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I had a particularly bad and reoccuring series of crashes (logged a bug about it even), then our sysadmin checked the machine and it turned out to be bad memory modules. Just saying – that can happen even in this enlightened day and age.
Technical Discussion » Gas Linear Combination for multiple field pairs
- riviera
- 1694 posts
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Hi,
I'm working on an asset that interpolates/blends between frames of a pyro sim, using the fields and velocities of the “current” and “next” frame. I'm doing the actual work within a DOP network, where I have two bunch of fields, called <density/heat/…>_current and <density/heat/…>_next.
Now, what I want to do is run a Gas Linear Combination microsolver on these field pairs (see screenshot). The only problem is that I don't just have a density current/next pair, but other fields as well (and using multiple nodes with hardcoded names is not an option).
I looked at the “Gas Each Data” solver which would almost be useful, except that I have to work with field pairs.
I have an ugly last-resort solution in mind that involves python, but I'd be happier if I could achieve this without resorting to trickery
Any ideas are appreciated
cheers,
imre
I'm working on an asset that interpolates/blends between frames of a pyro sim, using the fields and velocities of the “current” and “next” frame. I'm doing the actual work within a DOP network, where I have two bunch of fields, called <density/heat/…>_current and <density/heat/…>_next.
Now, what I want to do is run a Gas Linear Combination microsolver on these field pairs (see screenshot). The only problem is that I don't just have a density current/next pair, but other fields as well (and using multiple nodes with hardcoded names is not an option).
I looked at the “Gas Each Data” solver which would almost be useful, except that I have to work with field pairs.
I have an ugly last-resort solution in mind that involves python, but I'd be happier if I could achieve this without resorting to trickery
Any ideas are appreciated
cheers,
imre
Technical Discussion » $HIP is getting repeated twice in my file paths. ? $HIP/$HIP
- riviera
- 1694 posts
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darkczar
(…) someone from SESI replied to my question about this. They said that in Houdini “../” means “up one directory from $HIP”
That's very good to know, cheers
Technical Discussion » Digital Asset Disable/Hide Property
- riviera
- 1694 posts
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ConcernedCitizen
Sorry to rez, but I'd like to expand on the question. Under the “Hide When” on a property, can you put in a condition to hide a property when the digital asset's input is being used?
My digital asset has one input and if there is something plugged in to that input, I want to use the dimensions of the input's bounding box. If, however, there is nothing plugged in to the input, I want to show the user a Vector 3 for dimensions.
The way we do this in our assets is we create hidden (invisible) integer parameters (e.g. “_has_1st_input”) with a default expression that returns non-zero if the input is connected ( e.g. strcmp(opinputpath('.', 0), “”) ). Then we refer these parameters in the Disable When and/or Hide When fields (e.g. { _has_1st_input == 0 } ).
(I might remember the strcmp() results incorrectly, but the main idea is the same.) But I'm always open for better solutions
cheers
Technical Discussion » How buggy Houdini is.
- riviera
- 1694 posts
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danwood82
The UI issues can certainly be a problem sometimes I'd admit (although a LOT of them are very much improved in Houdini 14)
Yeah, but they're never as serious as he'd experienced, and crashes are very rare. IMHO if a 3d app keeps crashing around constantly, it's usually a video card driver problem.
danwood82
But when it comes to nodes not functioning correctly - well, if Houdini has taught me one thing over the years, it's that if you think there's a bug in functionality, check twice, check three times, and check again… because it almost always turns out to be something stupid I did.
Well, some operators are 10+ years old, so you can bump into silly things or even crashes. But reporting these usually gets them fixed by the devs in a next daily build. (they usually fix most small bugs in a few days or so)
Technical Discussion » How buggy Houdini is.
- riviera
- 1694 posts
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Well, the version of Houdini came out at February 26, 2012, meaning it's, hm, old. This, along with the fact you're on OSX (which IIRC had to get its own set of OpenGL fixes in just the latest beta) might be enough cause for frustration. Bug fixes come out on a daily basis (which is why usually it's a good idea to install the latest daily build first if you experience buggy behaviour.)
Actually you do sound like having GL/driver issues (knowing this from personal experience ), as Houdini itself is very stable. (I should go as far as saying it's one of the best in terms of both stability and support.)
Look into what you can do about updating your graphics driver (Maya, for instance “officially” works only with certain versions of drivers). Also, update at least the latest daily build of H12 available.
Actually you do sound like having GL/driver issues (knowing this from personal experience ), as Houdini itself is very stable. (I should go as far as saying it's one of the best in terms of both stability and support.)
Look into what you can do about updating your graphics driver (Maya, for instance “officially” works only with certain versions of drivers). Also, update at least the latest daily build of H12 available.
Technical Discussion » H15 - alt key and other quirks
- riviera
- 1694 posts
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Filip Tarczewski
I would like to make a case for taking a look at Blender's interface. Yes. Blender. Please, let me test your patience for a while, and tell you why I consider Blender's interface brilliant.
Sounds like a vim interface in 3d. I don't mind having options for accurate modeling (proper snapping, etc.) but honestly I doubt “brilliant” is the word.
Technical Discussion » acceleration blur?
- riviera
- 1694 posts
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Hi,
I just stumbled into this awesome feature of the htoa translator, called acceleration blur –
https://support.solidangle.com/display/AFHUG/Geometry+Properties+%3A%3A+Motion+Blur [support.solidangle.com]
This allows curved motion blurs for velocity vector-based motions (which is very useful for thing like sparks, etc). I'm not aware of similar in “regular” Houdini (but maybe I'm not up to date), do you guys think this could be done somehow in mantra?
cheers,
imre
I just stumbled into this awesome feature of the htoa translator, called acceleration blur –
https://support.solidangle.com/display/AFHUG/Geometry+Properties+%3A%3A+Motion+Blur [support.solidangle.com]
This allows curved motion blurs for velocity vector-based motions (which is very useful for thing like sparks, etc). I'm not aware of similar in “regular” Houdini (but maybe I'm not up to date), do you guys think this could be done somehow in mantra?
cheers,
imre
Technical Discussion » paint textures in viewport
- riviera
- 1694 posts
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In qLib there's an asset pair called UV PointCloud, where a SOP essentially generates a 3d point for each UV pixel (then you can apply colors to this point cloud with any method), and the COP counterpart which renders these points into a 2d texture.
(And Houdini handles the pcloud SOP->pcloud COP render->3d-view-texture interdependency pretty well.)
The first link below shows a wetmap technique that generates a 2d texture sequence.
(But naturally these are intended to be tools for procedurally generating UV-based textures, not for artistic-painterly purposes.)
https://www.facebook.com/video.php?v=872881069412345 [facebook.com]
https://www.facebook.com/qLibHoudini/photos/a.396009720432818.98425.145692112131248/872867132747072/?type=1 [facebook.com]
ps.: Actually, having another tool to convert the colored pointcloud into a ptex wouldn't be a bad idea (e.g. to use it as a base in a 3d paint app), but I'd be surprised if Houdini could write a ptex file.
(And Houdini handles the pcloud SOP->pcloud COP render->3d-view-texture interdependency pretty well.)
The first link below shows a wetmap technique that generates a 2d texture sequence.
(But naturally these are intended to be tools for procedurally generating UV-based textures, not for artistic-painterly purposes.)
https://www.facebook.com/video.php?v=872881069412345 [facebook.com]
https://www.facebook.com/qLibHoudini/photos/a.396009720432818.98425.145692112131248/872867132747072/?type=1 [facebook.com]
ps.: Actually, having another tool to convert the colored pointcloud into a ptex wouldn't be a bad idea (e.g. to use it as a base in a 3d paint app), but I'd be surprised if Houdini could write a ptex file.
Technical Discussion » H14: where is hitimpulse?
- riviera
- 1694 posts
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Bah, in the meantime I realized that I even read this on the beta forum. I just completely forgot about it in the meantime. (Especially the hitimpulse part).
What I use this for is to “jitter” bounces (apply some random rotation to particle velocity around the hit normal), basically simulating bumpy terrain/particle interaction. I use hitimpulse to separate particles that are practically rolling (small bounces) so they won't get randomized.
https://www.facebook.com/video.php?v=925742647459520&set=vb.145692112131248 [facebook.com]
(I nicked the idea from a 3dsmax particle system, heh heh and it often comes very handy. So I'm planning to take another look of which other convenience features to “borrow” )
Anyway, I was thinking of trying to replace the hitimpulse with a simple velocity magnitude checking, and see how that works out.
What I use this for is to “jitter” bounces (apply some random rotation to particle velocity around the hit normal), basically simulating bumpy terrain/particle interaction. I use hitimpulse to separate particles that are practically rolling (small bounces) so they won't get randomized.
https://www.facebook.com/video.php?v=925742647459520&set=vb.145692112131248 [facebook.com]
(I nicked the idea from a 3dsmax particle system, heh heh and it often comes very handy. So I'm planning to take another look of which other convenience features to “borrow” )
Anyway, I was thinking of trying to replace the hitimpulse with a simple velocity magnitude checking, and see how that works out.
Technical Discussion » H14: where is hitimpulse?
- riviera
- 1694 posts
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Okay.
Btw, today I happened to do something related (particle sims with/without impact data), and particle-geometry collision feels way faster in H14 than before (I had a heavy collision geo and quite some substepping, and the difference was noticeable). Which is great news, and really appreciated
Btw, today I happened to do something related (particle sims with/without impact data), and particle-geometry collision feels way faster in H14 than before (I had a heavy collision geo and quite some substepping, and the difference was noticeable). Which is great news, and really appreciated
Technical Discussion » H14: where is hitimpulse?
- riviera
- 1694 posts
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Thanks Jeff for the rapid answer.
Do you think it's reasonable to ask an RFE for a convenience switch (e.g. “Add Hit Impulse Attribute”) for this on the POP Solver? This change effectively makes us remember another “workaround” (not mentioning it break backwards compatibility for some popnets).
Besides, the attribute help page ( http://www.sidefx.com/docs/houdini14.0/dopparticles/attributes [sidefx.com] ) doesn't say anything – might be a good idea to mention how this attribute can be accessed.
(Although I'd rather prefer the switch on the solver, or something similar.)
Do you think it's reasonable to ask an RFE for a convenience switch (e.g. “Add Hit Impulse Attribute”) for this on the POP Solver? This change effectively makes us remember another “workaround” (not mentioning it break backwards compatibility for some popnets).
Besides, the attribute help page ( http://www.sidefx.com/docs/houdini14.0/dopparticles/attributes [sidefx.com] ) doesn't say anything – might be a good idea to mention how this attribute can be accessed.
(Although I'd rather prefer the switch on the solver, or something similar.)
Technical Discussion » H14: where is hitimpulse?
- riviera
- 1694 posts
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Hi,
I can't seem to get any hitimpulse attribute from POP collisions. I attached a very simple example scene to illustrate. My question is – am I being silly and missing something very simple, or should this report it as an issue? (I enabled all collision-related POP toggles I found)
cheers
I can't seem to get any hitimpulse attribute from POP collisions. I attached a very simple example scene to illustrate. My question is – am I being silly and missing something very simple, or should this report it as an issue? (I enabled all collision-related POP toggles I found)
cheers
Technical Discussion » RFE/discuss: A general "render in background" ROP
- riviera
- 1694 posts
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Hi,
I really like the new “Render in background” feature of geometry ROPs. Turns out that the ropnet variant can be abused to render entire ROP networks in the background (see image: if I press the Render in Background button on the Geometry ROP, the entire upstream network will be rendered as well).
This would be a very useful feature to “officially” have (unless it's there already and only I'm not aware of it?) Right now the above trick works even if all fields of the Geometry ROP are empty (no SOP node and/or no output file given).
What do you think?
cheers,
imre
I really like the new “Render in background” feature of geometry ROPs. Turns out that the ropnet variant can be abused to render entire ROP networks in the background (see image: if I press the Render in Background button on the Geometry ROP, the entire upstream network will be rendered as well).
This would be a very useful feature to “officially” have (unless it's there already and only I'm not aware of it?) Right now the above trick works even if all fields of the Geometry ROP are empty (no SOP node and/or no output file given).
What do you think?
cheers,
imre
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