Hi,
I am trying to figure out how to perform a multiple level point instancing (if it is possible with the current Houdini versions).
Basically:
disk file (a chunk for example) -> instanced on the first set of points (a particle simulation for example) -> instanced on second set of points (a grid layout for example)
On both levels, I need to have control on the transformation and access to the point attributes through cvex. I have tried bits and pieces with only one level. And obviously it all works. Manipulating “Xform” etc. But once I try to make a second level of instancing it all gets a bit confusing.
Any ideas?
Thanks.
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Technical Discussion » Multiple levels of instancing.
- symbolic
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Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
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Sorry, not yet. Well, I was looking at this in the following way:
If you have a particle SIM flowing along the Z axis, you will get some velocity already in there. Lots of details, as it is a particle SIM.
Then you take that SIM, time offset it and instance it on 24 points on a circle, and spin that circle. You would expect to get some motion blur due to the fact that the entire thing is spinning, but then also maintain some of the internal motion blur resulting from the velocity of your particles.
For now, I think I have solved the problem by attaching my procedural delay load for the particles on to a container object and then doing the spinning at object level. This kind of gave me some promising results, at least the simple prototype. Tonight I will render the real thing and evaluate the results tomorrow. If things are still broken, I will then contact support.
Thanks.
If you have a particle SIM flowing along the Z axis, you will get some velocity already in there. Lots of details, as it is a particle SIM.
Then you take that SIM, time offset it and instance it on 24 points on a circle, and spin that circle. You would expect to get some motion blur due to the fact that the entire thing is spinning, but then also maintain some of the internal motion blur resulting from the velocity of your particles.
For now, I think I have solved the problem by attaching my procedural delay load for the particles on to a container object and then doing the spinning at object level. This kind of gave me some promising results, at least the simple prototype. Tonight I will render the real thing and evaluate the results tomorrow. If things are still broken, I will then contact support.
Thanks.
Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
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Hi,
I have been playing around with INSTACING and CVEX. I came accross the following problem:
If I have a “v” attribute inside my cache that I am instancing on some points, I can manipulate the xform of the cache that is being instanced with CVEX and that also updates the “v” that is coming with the cache, however, it seems like it drops any motion blur that might have been caused by an animation on the actual points that we instance on.
Any ideas?
Thanks.
I have been playing around with INSTACING and CVEX. I came accross the following problem:
If I have a “v” attribute inside my cache that I am instancing on some points, I can manipulate the xform of the cache that is being instanced with CVEX and that also updates the “v” that is coming with the cache, however, it seems like it drops any motion blur that might have been caused by an animation on the actual points that we instance on.
Any ideas?
Thanks.
Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
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Hi,
Well, it was mostly my mistake (as usual). I forgot some instancing related render properties on the object level geo node that I was rendering so they were cutting off the procedural shaders and were doing a “point inctancing” instead of “procedural instancing”. So now things are better.
Thanks.
Well, it was mostly my mistake (as usual). I forgot some instancing related render properties on the object level geo node that I was rendering so they were cutting off the procedural shaders and were doing a “point inctancing” instead of “procedural instancing”. So now things are better.
Thanks.
Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
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I do not seem to be able to get anything into the CVEX context under 12.5, it seems to be totally broken. Under 12.0, I can print “P”, “v” etc. anything coming into there, but in 12.5, the print returns nothing.
I have been trying many different instancing approaches, they kind of work to get colour and time variations but the CVEX context proves to be useless at this point. I am aware that you can manipulate only translations, but … nothing seems to be working when it comes to CVEX.
I have been trying many different instancing approaches, they kind of work to get colour and time variations but the CVEX context proves to be useless at this point. I am aware that you can manipulate only translations, but … nothing seems to be working when it comes to CVEX.
Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
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Well, it seems like things are slightly more complicated. I got various aspects of the instancing to work, but could not make the CVEX actually do anything. As a starters I am trying to manipulate “P” in some simple fashion, but even that seems to be doing nothing. Is there something special that needs to be done in order to get CVEX working?
Thanks.
Thanks.
Technical Discussion » Accessing attributes from Instance Points to use in CVEX
- symbolic
- 107 posts
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Hi,
I have a cache of particles that has been simmed in the centre of my scene. It is a simple particle SIM with particles flowing along the Z axis.
I would like to instance that cache with a time offset on the points of a circle that is spinning.
I am using the Delay Load Procedural to read in the cache at render time. The question is this:
I strongly believe that I need to fix my “v” vector before the cache is passed to the renderer as the transformation is irrelevant to the actual SIM position. So I believe that I need to find a way of passing a matrix attribute from my instance points, so I can update the my velocity vector before things get rendered, and no need to mention that I am using the velocity for the motion blur calculations.
Any idea about how to do that?
Thanks.
I have a cache of particles that has been simmed in the centre of my scene. It is a simple particle SIM with particles flowing along the Z axis.
I would like to instance that cache with a time offset on the points of a circle that is spinning.
I am using the Delay Load Procedural to read in the cache at render time. The question is this:
I strongly believe that I need to fix my “v” vector before the cache is passed to the renderer as the transformation is irrelevant to the actual SIM position. So I believe that I need to find a way of passing a matrix attribute from my instance points, so I can update the my velocity vector before things get rendered, and no need to mention that I am using the velocity for the motion blur calculations.
Any idea about how to do that?
Thanks.
Houdini Lounge » Flipbook sub-frames?
- symbolic
- 107 posts
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Hi,
H11.0.775 (linuix) here, I am not able to playback sub-frames in my flipbooks. I tried everything, all playback settings and flipbook options has 0.1 in there, and no matter what I do I can not view my subframe results in the flipbook. Well, I can see them as they cook, but then as soon as the flipbook starts to play, it only plays integer frames?! It was not like that on H10?!
Am I the only one who needs this function?
Any ideas? Thanks.
H11.0.775 (linuix) here, I am not able to playback sub-frames in my flipbooks. I tried everything, all playback settings and flipbook options has 0.1 in there, and no matter what I do I can not view my subframe results in the flipbook. Well, I can see them as they cook, but then as soon as the flipbook starts to play, it only plays integer frames?! It was not like that on H10?!
Am I the only one who needs this function?
Any ideas? Thanks.
Technical Discussion » Error checking for specific Houdini variables.
- symbolic
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Sure. Sorry for double posting. Lets continue there:
http://forums.odforce.net/index.php?/topic/14268-variable-checking/ [forums.odforce.net]
(I already tried to improve my question)
Thanks.
http://forums.odforce.net/index.php?/topic/14268-variable-checking/ [forums.odforce.net]
(I already tried to improve my question)
Thanks.
Technical Discussion » Error checking for specific Houdini variables.
- symbolic
- 107 posts
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Hi,
(I am not sure if this message will make it through, lets hope that it does)
I am trying to check the existence Houdini specific variables (Not ENVIRONMENT variables).
I am using, for example:
echo `isvariable(“VER”), this returns 1
but then:
echo `ishvariable(“MAPU”), this returns 0
echo `ishvariable(“PT”), this returns 0
$MAPU and $PT are Houdini variables, why the check returns 0 (FALSE)?
Any ideas?
Thanks.
(I am not sure if this message will make it through, lets hope that it does)
I am trying to check the existence Houdini specific variables (Not ENVIRONMENT variables).
I am using, for example:
echo `isvariable(“VER”), this returns 1
but then:
echo `ishvariable(“MAPU”), this returns 0
echo `ishvariable(“PT”), this returns 0
$MAPU and $PT are Houdini variables, why the check returns 0 (FALSE)?
Any ideas?
Thanks.
Technical Discussion » Frame by frame caching (as you playback frames.)
- symbolic
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Technical Discussion » Frame by frame caching (as you playback frames.)
- symbolic
- 107 posts
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Thanks Peter,
Well, I usually try to avoid the cacheSOP since I always forget it somewhere in my networks and it causes a bit of mess So that's why I did not know about this function. I thought that we always need to press that “Cache” button. Embarrassing
Anyway, I am using it now and it works, as it caches any frame being cooked. Thanks. It is pity that it cannot do subframes.
WhoDjini: Yes you are right, but then keeping track of those files is a bit hard, they keep overwriting each other, there is a need for unique names etc., then you forget to clean them up. Besides, I am always cautious to delete any files with scripts when working inside complex proprietary pipelines.
Well, I usually try to avoid the cacheSOP since I always forget it somewhere in my networks and it causes a bit of mess So that's why I did not know about this function. I thought that we always need to press that “Cache” button. Embarrassing
Anyway, I am using it now and it works, as it caches any frame being cooked. Thanks. It is pity that it cannot do subframes.
WhoDjini: Yes you are right, but then keeping track of those files is a bit hard, they keep overwriting each other, there is a need for unique names etc., then you forget to clean them up. Besides, I am always cautious to delete any files with scripts when working inside complex proprietary pipelines.
Technical Discussion » Frame by frame caching (as you playback frames.)
- symbolic
- 107 posts
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Hi,
I am trying to get a “caching process” per every new frame. Something like a “Cache SOP” attached to a network… and every time you press (+) on the time-line to advance one frame forward it stores the result. Then when you scrub between the range that you have already played it plays it in real-time.
Cache SOP will do it, but you know how you just hit the cache button and it stays there totally freezing Houdini until the caching is done.
I can possibly cheat by writing out dummy cache files to the $HOUDIN_TMP but I do not really want to fill the $TMP with crap.
Or maybe there is a way to access and make the Cache SOP do a one frame by one frame cache, with some options that can be scripted later?
Any ideas?
Thanks.
I am trying to get a “caching process” per every new frame. Something like a “Cache SOP” attached to a network… and every time you press (+) on the time-line to advance one frame forward it stores the result. Then when you scrub between the range that you have already played it plays it in real-time.
Cache SOP will do it, but you know how you just hit the cache button and it stays there totally freezing Houdini until the caching is done.
I can possibly cheat by writing out dummy cache files to the $HOUDIN_TMP but I do not really want to fill the $TMP with crap.
Or maybe there is a way to access and make the Cache SOP do a one frame by one frame cache, with some options that can be scripted later?
Any ideas?
Thanks.
Technical Discussion » Basics of a simple Houdini pipeline / prod. environment.
- symbolic
- 107 posts
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Hi, a quick update. I spent some time researching about how env. variables have an influence on the way Houdini work. And it was very helpful. I realised the strength of writing wrapper scripts in order to set up the vital variables, also the meaning of a default Houdini folder structure. This post has been very helpful.
Thanks.
Thanks.
Technical Discussion » Basics of a simple Houdini pipeline / prod. environment.
- symbolic
- 107 posts
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(This has already been posted on odForce: Still, I would like to get some ideas from here as well. Hope this is ok.)
Hi,
I have been playing around with setting up a simple production environment for Houdini. I have been working in various environments myself (school, companies etc.) but never had time to explore the scripts, settings and the actual environment required for a healthy Houdini based pipe-line.
I have to admit, a question like that has a very broad range of answers.
But I would like to ask for your ideas anyway. I am familiar with the initial scripts run when you fire-up Houdini, also things like customizing the “Right Mouse Button” etc. There is already a nice wiki about it as many of you might already know: CustomizingHoudini
So what are your critical tips for an efficient pipe-line / environment, things like $PROJECT $SHOT $SCRIPTS, things included in the 123, 456 and any start up script etc?
Thanks and Happy New Year!, Merry Christmas!
Hi,
I have been playing around with setting up a simple production environment for Houdini. I have been working in various environments myself (school, companies etc.) but never had time to explore the scripts, settings and the actual environment required for a healthy Houdini based pipe-line.
I have to admit, a question like that has a very broad range of answers.
But I would like to ask for your ideas anyway. I am familiar with the initial scripts run when you fire-up Houdini, also things like customizing the “Right Mouse Button” etc. There is already a nice wiki about it as many of you might already know: CustomizingHoudini
So what are your critical tips for an efficient pipe-line / environment, things like $PROJECT $SHOT $SCRIPTS, things included in the 123, 456 and any start up script etc?
Thanks and Happy New Year!, Merry Christmas!
Technical Discussion » ATI graphic cards
- symbolic
- 107 posts
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Excuse my french but:
I think investing in ATI hardware is a mistake. It has been always unrealisable and flaky. I have a MacBook Pro (A1151) and god knows what kind of crazy stuff I had to do, just to get OpenGL working with that ATI X1600 (on Linux). One may argue and say “Yeah, but that is an old model, and it is Linux blah blah”. Well I have seen enough crappy ATIs on every possible platform. Trust me. The only reason I am staying away from Dell is that they have those crappy ATIs as well (edit: and by that, I mean anything that has ATI in it, especially laptops like Studio 15). Such a shame!
I think investing in ATI hardware is a mistake. It has been always unrealisable and flaky. I have a MacBook Pro (A1151) and god knows what kind of crazy stuff I had to do, just to get OpenGL working with that ATI X1600 (on Linux). One may argue and say “Yeah, but that is an old model, and it is Linux blah blah”. Well I have seen enough crappy ATIs on every possible platform. Trust me. The only reason I am staying away from Dell is that they have those crappy ATIs as well (edit: and by that, I mean anything that has ATI in it, especially laptops like Studio 15). Such a shame!
Technical Discussion » Wrinkles - What would be the best way?
- symbolic
- 107 posts
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Thanks! That was very helpfull. Helped me to figure out lots of things
Not just wrinkles.
Not just wrinkles.
Technical Discussion » Wrinkles - What would be the best way?
- symbolic
- 107 posts
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Hi,
I have seen that these has been a pot on this:
http://forums.odforce.net/index.php?/topic/3989-houdini-boxer/page__hl__wrinkle__fromsearch__1 [forums.odforce.net]
However, It was not very clear to me, in terms of how to achieve this effect. I am trying to get some “wrinkling” around the limbs of a creature (animal). Is this usually a custom deformer or are there already built in Houdini tools for that? (I am not very familiar with character stuff in Houdini)
Maybe a sopsolver? Maybe a cloth thing?
Any ideas?
Thanks.
I have seen that these has been a pot on this:
http://forums.odforce.net/index.php?/topic/3989-houdini-boxer/page__hl__wrinkle__fromsearch__1 [forums.odforce.net]
However, It was not very clear to me, in terms of how to achieve this effect. I am trying to get some “wrinkling” around the limbs of a creature (animal). Is this usually a custom deformer or are there already built in Houdini tools for that? (I am not very familiar with character stuff in Houdini)
Maybe a sopsolver? Maybe a cloth thing?
Any ideas?
Thanks.
Technical Discussion » Flow Path Object / Deform Along Curve
- symbolic
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Technical Discussion » Flow Path Object / Deform Along Curve
- symbolic
- 107 posts
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It worked. Thanks for the idea. The creep part is a bit manual. In terms of figuring out the length of the sweeped geo and then the propotions to fit the actual geometry on the sweeped surface. The mesh that drives the creep is 2D at the end right? it is just a nurbs surface generated from the line sweep?
Thanks.
Thanks.
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