Moin,
maybe you forgot to do the deformation step in the rigging process - you can always add that manually, just dive into your rig folder, find the geometry import and add a deform node at the end of that thread. Should work pretty straight forward once you find the nodes.
Marc
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Houdini Indie and Apprentice » AutoRig Issues
- malbrecht
- 806 posts
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Houdini Learning Materials » FEM mixamo animation
- malbrecht
- 806 posts
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Moin,
I don't fully get what you are after (“collide with ground and such” - do you have a ground plane?) … but I have used FEM (for “cloth” solving) in Houdini successfully on movie shots importing animated characters from the pipeline (using Alembic Caches).
If your character “falls through the ground” my assumption is that you don't have a ground plane it can collide with. Could you get a bit more specific about the problems you are having?
I will do a walkthrough on one of my shots ASAP, but unfortunately my Pateron does not yet bring in enough money to allow for the time such videos take, so this may be a bit further down the month.
Marc
I don't fully get what you are after (“collide with ground and such” - do you have a ground plane?) … but I have used FEM (for “cloth” solving) in Houdini successfully on movie shots importing animated characters from the pipeline (using Alembic Caches).
If your character “falls through the ground” my assumption is that you don't have a ground plane it can collide with. Could you get a bit more specific about the problems you are having?
I will do a walkthrough on one of my shots ASAP, but unfortunately my Pateron does not yet bring in enough money to allow for the time such videos take, so this may be a bit further down the month.
Marc
Technical Discussion » How could I learn to writing scripts that record instancing object transforms data and some more to XML, T3D files like these videos?
- malbrecht
- 806 posts
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Moin,
VEX can not write to files directly (you could use a cache file node, though, and use an external script to deal with the content). But you can use a python node (sic!) to write geometry data to a file. That's pretty straight forward - but yes, you might need to learn a tiny bit of Python and you might learn a bit about “scripting nodes” in Houdini.
If you are slightly savy with programming in any context, it's relatively quick to grasp.
Marc
VEX can not write to files directly (you could use a cache file node, though, and use an external script to deal with the content). But you can use a python node (sic!) to write geometry data to a file. That's pretty straight forward - but yes, you might need to learn a tiny bit of Python and you might learn a bit about “scripting nodes” in Houdini.
If you are slightly savy with programming in any context, it's relatively quick to grasp.
Marc
Technical Discussion » I am new to Houdini and I am have what seems to be major issues
- malbrecht
- 806 posts
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> How can a license be Rental and non commercial at the same time? This is for the render.
easy. It's a LICENSE. It's quite common to issue (even free) licenses, that may be limited e.g. in render size or track numbers or word count or whatever, for learning purposes, which you then may not use for commercial purposes.
Even with some moderate license fee you may be limmited to non-commercial work (look at Microsoft's non-commercial Office packets that they used to sell for nutshells, you had to buy a license but weren't allowed to use the tools commercially - I could imagine they do the same now with their office 365).
Just something to shrug about and go on having fun.
Marc
easy. It's a LICENSE. It's quite common to issue (even free) licenses, that may be limited e.g. in render size or track numbers or word count or whatever, for learning purposes, which you then may not use for commercial purposes.
Even with some moderate license fee you may be limmited to non-commercial work (look at Microsoft's non-commercial Office packets that they used to sell for nutshells, you had to buy a license but weren't allowed to use the tools commercially - I could imagine they do the same now with their office 365).
Just something to shrug about and go on having fun.
Marc
Technical Discussion » I am new to Houdini and I am have what seems to be major issues
- malbrecht
- 806 posts
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… that's why I suggested that. You most likely are having an issue getting the license set up correctly. Support will be able to get you flying.
Marc
Marc
Technical Discussion » I am new to Houdini and I am have what seems to be major issues
- malbrecht
- 806 posts
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Moin, Alexander,
you might want to deal with problems like this with support (just email them the error reports you got) - different to other companies, SideFX actually *does* care about their users and is quite fast with email responses.
The license messages you are getting point towards the license not having been installed correctly. Try running the license manager ONCE as administrator, install your license (that you got by email, probably), make sure it is available in the listing (it is possible that your license user account has a different password to your SideFX-website account, so make sure that you could actually retrieve the license! Many people just ignore error messages at this stage.)
You should try running Houdini as a standard user, not as an administrator. It is well possible that access rights issues result from you trying it to run as an adminstrator (note that “having all rights” does not necessarily mean “having the right rights” - just because a president believes to have all the rights, doesn't mean he's doing right!)
Marc
you might want to deal with problems like this with support (just email them the error reports you got) - different to other companies, SideFX actually *does* care about their users and is quite fast with email responses.
The license messages you are getting point towards the license not having been installed correctly. Try running the license manager ONCE as administrator, install your license (that you got by email, probably), make sure it is available in the listing (it is possible that your license user account has a different password to your SideFX-website account, so make sure that you could actually retrieve the license! Many people just ignore error messages at this stage.)
You should try running Houdini as a standard user, not as an administrator. It is well possible that access rights issues result from you trying it to run as an adminstrator (note that “having all rights” does not necessarily mean “having the right rights” - just because a president believes to have all the rights, doesn't mean he's doing right!)
Marc
Houdini Indie and Apprentice » Bone capture workflow
- malbrecht
- 806 posts
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Moin,
I go through a few approaches on dealing with this problem in my “leg rig” video series (have a look at my Vimeo channel - I have been told that video tutorials suck and watching them is a waste of time, so, since I don't know if you like videos, I'll leave it at that )
One way is to have polygongroups set up so that you can limit the weight distribution to only those areas that you want to be affected. That sounds tedious at first, but is actually very easy to use.
The weighting spreadsheet can be of help, too, again with some groups set up for faster access.
You could, in theory, create separate weighting “threads” and combine those in a wrangle node at the end, having access to your own normalization process, but I assume this is way too complex for a “standard” situation (it might make sense if you are talking about hundreds or even thousands of “points with issues”).
Marc
I go through a few approaches on dealing with this problem in my “leg rig” video series (have a look at my Vimeo channel - I have been told that video tutorials suck and watching them is a waste of time, so, since I don't know if you like videos, I'll leave it at that )
One way is to have polygongroups set up so that you can limit the weight distribution to only those areas that you want to be affected. That sounds tedious at first, but is actually very easy to use.
The weighting spreadsheet can be of help, too, again with some groups set up for faster access.
You could, in theory, create separate weighting “threads” and combine those in a wrangle node at the end, having access to your own normalization process, but I assume this is way too complex for a “standard” situation (it might make sense if you are talking about hundreds or even thousands of “points with issues”).
Marc
Technical Discussion » Cartoon main autorig H16
- malbrecht
- 806 posts
- Offline
Moin,
your question seems a bit unspecific. You don't want to put keyframes into a rig, obviously, but on controlling “items” (nulls or whatever you want to call them).
If you do not want to extend the autorig-created setup to add your own animation controls (which I would suggest doing), you can grab the pose tool and start posing your character. Whenever you grab a “bone” to “animate” it, you can set keyframes on those channels that you modify - do it once in autokey-mode to tell Houdini that you want these to be autokeyed, then Houdini will capture later tweaks automatically.
Does this answer your question? Else, could you be a bit more specific about how far you got and where you don't know how to proceed further?
Marc
your question seems a bit unspecific. You don't want to put keyframes into a rig, obviously, but on controlling “items” (nulls or whatever you want to call them).
If you do not want to extend the autorig-created setup to add your own animation controls (which I would suggest doing), you can grab the pose tool and start posing your character. Whenever you grab a “bone” to “animate” it, you can set keyframes on those channels that you modify - do it once in autokey-mode to tell Houdini that you want these to be autokeyed, then Houdini will capture later tweaks automatically.
Does this answer your question? Else, could you be a bit more specific about how far you got and where you don't know how to proceed further?
Marc
Houdini Indie and Apprentice » Hair Collisions
- malbrecht
- 806 posts
- Offline
He … didn't want to lecture anyone. If you feel like that was “too much text that didn't help anyone” (I guess you were looking into some mirror?) … I'll just shut up and don't look at your other post. (Hint: I am not reading the forums every day but was interested in the hair topic.)
Yeah - signing off now, don't want to roll you over with “lots of text”.
Marc
Yeah - signing off now, don't want to roll you over with “lots of text”.
Marc
Houdini Indie and Apprentice » Hair Collisions
- malbrecht
- 806 posts
- Offline
Adriano, I am sure that questions about -insertarbitrarytopic- are not “ignored” as you put it.
But with a problem that points to a local issue with the computer used OR the very specific scene file, it is almost impossible to *guess* what a solution could be without having access to at least the scene file.
The thread opener stated that he got the system as such working (wire solver), so he doesn't exactly ask anything about “hair dynamics” as you claim, but about “why does my scene hang up Houdini”, which, like mentioned above, may be a local thing limited to his system and/or setup.
If you have a question about hair dynamics - try asking it. Since the thread opener has a setup that seems to work for hair dynamics (just not for rendering/flipbooking :-) ), he might even be able to answer your question ;-)
Marc
But with a problem that points to a local issue with the computer used OR the very specific scene file, it is almost impossible to *guess* what a solution could be without having access to at least the scene file.
The thread opener stated that he got the system as such working (wire solver), so he doesn't exactly ask anything about “hair dynamics” as you claim, but about “why does my scene hang up Houdini”, which, like mentioned above, may be a local thing limited to his system and/or setup.
If you have a question about hair dynamics - try asking it. Since the thread opener has a setup that seems to work for hair dynamics (just not for rendering/flipbooking :-) ), he might even be able to answer your question ;-)
Marc
Technical Discussion » Simple VEX Question
- malbrecht
- 806 posts
- Offline
Moin, Floyd,
currently VEX does not seem to support calculations/autocasts on assignments. Casting a vector from a single float is an overloaded function (“autocasting” from a single value to three) - and that, too, is not supported (yet?).
You can wrap the cast into a function, though: By writing
you use the “workaround” of sending your float “test” to a function first that takes care of the casting and returns a vector for the interpreter to use for “@P”.
Marc
currently VEX does not seem to support calculations/autocasts on assignments. Casting a vector from a single float is an overloaded function (“autocasting” from a single value to three) - and that, too, is not supported (yet?).
You can wrap the cast into a function, though: By writing
@P = @P * set(test);
Marc
Houdini Lounge » Anyone tried a Surface Book with Houdini 16
- malbrecht
- 806 posts
- Offline
Moin,
not a surface *book*, but I have been using Houdini on my “rock steady off road” Surface 2 pro to showcase its (Houdini's) usage to a client I was working with.
He now seriously considers buying a few (Surfaces).
Marc
not a surface *book*, but I have been using Houdini on my “rock steady off road” Surface 2 pro to showcase its (Houdini's) usage to a client I was working with.
He now seriously considers buying a few (Surfaces).
Marc
Technical Discussion » Rigging a Horse - forward movement in houdini
- malbrecht
- 806 posts
- Offline
Moin,
> But i was wondering if any Houdini user ever found a procedural way to make the horse go forward at the correct speed.
I am not sure that I fully get what you mean by “go forward at the correct speed”. Horses don't just speed up their motion vectors when “going faster”, they will usually make wider steps. So if your basic animation is laid out well (*NOT* motion captured or if so, then tweaked and edited so that you can refine it), you can, to some degree, lengthen the steps but *may* have to change the overall timing (not a good method for “game accuracy”, i.e. you want to stay within, say, 24 frames).
> (in a way that would make it possible to blend between trot and gallop after 40 meters for example)
You would need the passing phase from trot to gallop, it's not a simple change “this frame = trot”, “this frame = gallop”. Again, as long as you are not talking about game optics.
> Anybody ever did something similar by any chance?
Yes, and it is not trivial.
> And I was wondering if you know any kind of mathematics or method to calculate the speed of a horse moving forward in a animation?
Just take the touch down moment in your animation (foot hits ground) and measure the distance covered until lift off. You can do that even with animations that run “in place”, since the hoof will still move the distance within local space of the animation. Together with the fps rate of your animation you basically have the speed the horse is moving at.
Marc
> But i was wondering if any Houdini user ever found a procedural way to make the horse go forward at the correct speed.
I am not sure that I fully get what you mean by “go forward at the correct speed”. Horses don't just speed up their motion vectors when “going faster”, they will usually make wider steps. So if your basic animation is laid out well (*NOT* motion captured or if so, then tweaked and edited so that you can refine it), you can, to some degree, lengthen the steps but *may* have to change the overall timing (not a good method for “game accuracy”, i.e. you want to stay within, say, 24 frames).
> (in a way that would make it possible to blend between trot and gallop after 40 meters for example)
You would need the passing phase from trot to gallop, it's not a simple change “this frame = trot”, “this frame = gallop”. Again, as long as you are not talking about game optics.
> Anybody ever did something similar by any chance?
Yes, and it is not trivial.
> And I was wondering if you know any kind of mathematics or method to calculate the speed of a horse moving forward in a animation?
Just take the touch down moment in your animation (foot hits ground) and measure the distance covered until lift off. You can do that even with animations that run “in place”, since the hoof will still move the distance within local space of the animation. Together with the fps rate of your animation you basically have the speed the horse is moving at.
Marc
Houdini Indie and Apprentice » Rendering an Animation to a Video File?
- malbrecht
- 806 posts
- Offline
I explain how to use mplay to create a video file from the rendered image frames in the second part of this quick tip:
Marc
Marc
Edited by malbrecht - July 5, 2017 02:53:32
Houdini Indie and Apprentice » What is UV?
- malbrecht
- 806 posts
- Offline
Moin, Scott,
it might make sense if you read up on “3d terminology” in general. There are some expressions that you should be familiar with in order to - later on - ask questions in a way other users can understand. Please don't take this as an offence!
UV is such a fundamental concept in 3d that you might just google it
In short - to my knowledge the actual NAMING doesn't have a “meaning” just like “xyz” or “abc” don't have a “meaning” except for being consecutive letters. abc usually is used for variables in some mathematical context or angles on a shape, xyz is used to denominate 3 axis in a 3d space and uv is used for the 2 axis of a 2d space value. In 3d “uv” refers to both material information during rendertime (each polygon/face/primitive - all just expressions for the same idea - is described by its corner points/vertices, but when rendering, you can still have additional geographic information INSIDE the polygon, for normals, bump maps, color etc.). Since the surface of the polygon is understood as a 2d space (even if the polygon is non-planar), you can IGNORE the 3rd dimension on each corner point of the polygon and just see it as 2-dimensional, so that each point inside the polygon can be interpolated onto a standardized, normalized (i.e. square, 0-1 length/height) uv coordinate. By interpolating any point on the surface of the polygon to the normalized 2d space of the uv map, you get unique, exact information about whatever MAP (color, bump etc) you want to read out.
OK … if that was short, you probably don't want to read the long version.
Marc
it might make sense if you read up on “3d terminology” in general. There are some expressions that you should be familiar with in order to - later on - ask questions in a way other users can understand. Please don't take this as an offence!
UV is such a fundamental concept in 3d that you might just google it
In short - to my knowledge the actual NAMING doesn't have a “meaning” just like “xyz” or “abc” don't have a “meaning” except for being consecutive letters. abc usually is used for variables in some mathematical context or angles on a shape, xyz is used to denominate 3 axis in a 3d space and uv is used for the 2 axis of a 2d space value. In 3d “uv” refers to both material information during rendertime (each polygon/face/primitive - all just expressions for the same idea - is described by its corner points/vertices, but when rendering, you can still have additional geographic information INSIDE the polygon, for normals, bump maps, color etc.). Since the surface of the polygon is understood as a 2d space (even if the polygon is non-planar), you can IGNORE the 3rd dimension on each corner point of the polygon and just see it as 2-dimensional, so that each point inside the polygon can be interpolated onto a standardized, normalized (i.e. square, 0-1 length/height) uv coordinate. By interpolating any point on the surface of the polygon to the normalized 2d space of the uv map, you get unique, exact information about whatever MAP (color, bump etc) you want to read out.
OK … if that was short, you probably don't want to read the long version.
Marc
Houdini Indie and Apprentice » Learning tips
- malbrecht
- 806 posts
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Moin,
not sure how serious the question is meant - I mean, obviously you can only learn something if you practise it, not from watching tutorials. That goes for Houdini via pizza baking to dealing with your spouse. That's so fundamental that I somehow cannot really follow the question:
Tutorials and books and, of course, mestela's world famous cgwiki, that you probably learnt by heart by now, just for *understanding* things better, not for “learning” them.
You learn a language by speaking it, listening, trying to understand, making mistakes, correcting your mistakes.
You use a dictionary or a grammar book to check for specific details that you are unclear about or to get inspirations for idioms you didn't know before.
You learn Houdini by using it, disecting other people's work (sample files), trying to understand, making mistakes, correcting your mistakes.
You use tutorials, books and whatsnots to check for specific details that you are unclear about or to get inspirations for tricks or effects you didn't know before.
That said: There does not seem to be a golden rule for tutorials/books etc. What works for the one is completely useless for the other. I personally found Mr. Moncrief's “easy-peasy” introductions helpful, but I also loved Dan Ablan's work on other platforms, obviously both aren't everybody's favorites and for sure you don't learn the “nuts and bolts” by following some loose, simplified projects.
I would love to know what specifically you are looking for in tutorials, written articles, maybe podcasts, because MAKING those is a hobby for me that I would love to extend.
Marc
not sure how serious the question is meant - I mean, obviously you can only learn something if you practise it, not from watching tutorials. That goes for Houdini via pizza baking to dealing with your spouse. That's so fundamental that I somehow cannot really follow the question:
Tutorials and books and, of course, mestela's world famous cgwiki, that you probably learnt by heart by now, just for *understanding* things better, not for “learning” them.
You learn a language by speaking it, listening, trying to understand, making mistakes, correcting your mistakes.
You use a dictionary or a grammar book to check for specific details that you are unclear about or to get inspirations for idioms you didn't know before.
You learn Houdini by using it, disecting other people's work (sample files), trying to understand, making mistakes, correcting your mistakes.
You use tutorials, books and whatsnots to check for specific details that you are unclear about or to get inspirations for tricks or effects you didn't know before.
That said: There does not seem to be a golden rule for tutorials/books etc. What works for the one is completely useless for the other. I personally found Mr. Moncrief's “easy-peasy” introductions helpful, but I also loved Dan Ablan's work on other platforms, obviously both aren't everybody's favorites and for sure you don't learn the “nuts and bolts” by following some loose, simplified projects.
I would love to know what specifically you are looking for in tutorials, written articles, maybe podcasts, because MAKING those is a hobby for me that I would love to extend.
Marc
Houdini Indie and Apprentice » Moved to Linux— need to build VFX Platform?
- malbrecht
- 806 posts
- Offline
… with that said: If you aren't going to develop (outside VEX, Python, HScript etc), you don't need a compiler (GCC). I would consider the link to the VFX reference platform just as what it is named: A REFERENCE, not a 1:1 requirement. When in doubt what to go for, you can find “commonly agreed upon specifications” there.
Best thing when trying to switch to Linux, however, is not to have doubts in the first place (says the guy who just wasted over 20 hours of his life installing CentOS for some Houdini tests - what a loss!)
Marc
Technical Discussion » Slow Viewport response
- malbrecht
- 806 posts
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Moin, Bryan,
have you seen this other thread about slow viewport performance - and tried the suggestions made there?
https://www.sidefx.com/forum/topic/48607/ [www.sidefx.com]
Marc
have you seen this other thread about slow viewport performance - and tried the suggestions made there?
https://www.sidefx.com/forum/topic/48607/ [www.sidefx.com]
Marc
Technical Discussion » Rigid Body Issue
- malbrecht
- 806 posts
- Offline
Moin,
well … you didn't ask questions, so answers are hard to come up with :-D
Depending on how you set up your scene, your simulation and your Espresso, you should find a “mass” definition in the RBD objects' “physical” tab (you can either specify density or mass, but both really only give some RELATIVE numbers against other objects, in the end you will want to “art direct” the behavior of the objects more than a “real” physical calculation). It is possible that you want to play with dampening values for individual objects more than relying on maybe-realistic calculations.
Also depending on your scene setup you will probably want to vary the glue value that keeps together parts of your ground construction. Giving it higher strength values where you want less destruction et vice versa - or you only “deconstruct” those areas that you want to destroy and leave the rest intact to begin with. What *looks* best really depends on what you need, what you have and how you set things up.
Marc
well … you didn't ask questions, so answers are hard to come up with :-D
Depending on how you set up your scene, your simulation and your Espresso, you should find a “mass” definition in the RBD objects' “physical” tab (you can either specify density or mass, but both really only give some RELATIVE numbers against other objects, in the end you will want to “art direct” the behavior of the objects more than a “real” physical calculation). It is possible that you want to play with dampening values for individual objects more than relying on maybe-realistic calculations.
Also depending on your scene setup you will probably want to vary the glue value that keeps together parts of your ground construction. Giving it higher strength values where you want less destruction et vice versa - or you only “deconstruct” those areas that you want to destroy and leave the rest intact to begin with. What *looks* best really depends on what you need, what you have and how you set things up.
Marc
Houdini Indie and Apprentice » Geometry as a volume
- malbrecht
- 806 posts
- Offline
Moin, Anna,
there is a difference between “volume” and “vdb”, that's probably why you got stuck. While a vdb actually “is a volume”, the benefits of VDB are, amongst others, that no data gets stored when there are no voxels, so you can safe a lot of memory footprint / bandwidth.
If you *want* to convert a VDB into a volume (loosing the benefits of vdb), you can use a
A “volume” (including a vdb) always is a box in its outer boundaries, because that is how the cell collection is set up (x/y/z), however the axis can have different sizes and so can the resolution/axis.
I hope this helps!
Marc
there is a difference between “volume” and “vdb”, that's probably why you got stuck. While a vdb actually “is a volume”, the benefits of VDB are, amongst others, that no data gets stored when there are no voxels, so you can safe a lot of memory footprint / bandwidth.
If you *want* to convert a VDB into a volume (loosing the benefits of vdb), you can use a
convert vdb
node (http://www.sidefx.com/docs/houdini/nodes/sop/convertvdb [www.sidefx.com] ).A “volume” (including a vdb) always is a box in its outer boundaries, because that is how the cell collection is set up (x/y/z), however the axis can have different sizes and so can the resolution/axis.
I hope this helps!
Marc
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