Jump to content

Search the Community

Showing results for tags 'constraint'.



More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • General
    • Lounge/General chat
    • Education
    • Jobs
  • Houdini
    • General Houdini Questions
    • Effects
    • Modeling
    • Animation & Rigging
    • Lighting & Rendering
    • Compositing
    • Games
    • Tools (HDA's etc.)
  • Coders Corner
    • HDK : Houdini Development Kit
    • Scripting
    • Shaders
  • Art and Challenges
    • Finished Work
    • Work in Progress
    • VFX Challenge
    • Effects Challenge Archive
  • Systems and Other Applications
    • Other 3d Packages
    • Operating Systems
    • Hardware
    • Pipeline
  • od|force
    • Feedback, Suggestions, Bugs

Found 68 results

  1. Hi. I want to make activation and constraint coexist to get this↓ result. I made RnD, but it doesn't work. How should I modify it? Active_RnD.hip
  2. Hey there, I'm working on a project for my master degree and i'm having an issue with glue constraint in my DOP network. It was working well until I deleted all the geometry and imported a new version of it from Maya. The ball should go through the wall and destroy the tower partially (just the active points), but it just bounces off. Could someone please explain me how to solve this issue? It's really urgent. Attached you can find my Houdini scene. Thanks in advance! Tower_16_more_windows.hipnc
  3. Hello everyone, the project > I'm working on short animations of a shirt flying in the wind. I decided to use houdini to learn it and use the new vellum solver. I managed to have really nice and quick result for most of the shirts but one of them give me some troubles.. problem 1 > One of the shirt is more like a polo so I would like to set differents constraints on the collar to make it more stiff than the rest. I tried to make groups and merge them but I think I'm missing something because it's not working. I can't find any related topics either.. maybe you guys can give me a clue on how to make this work ? I'm ready to experiment I just don't know where to search anymore.. problem 2 > On the same shirt there is 2 buttons. I'd like to glue them to the shirt for them to react like rigid body and follow the shirt mouvement but I don't understand how I can do it and how to place those news constraints in the graph.. First screenshot is a view of the collar and the buttons placement. It's a model from Marvelous Designer. Next a screenshot of the network view and third a view of the collar being not stiff enough ( : I can only do screenshoots of the shirt and can't really share my hip file because the design of the shirt is not supposed to be released yet. Thank you for the reading !
  4. Vellum string constraint break

    Hi everyone, I'm currently having trouble with breaking a vellum string object in half. The idea is to make a saliva strand that's stretching before breaking in the middle. Currently i have a line that's vellum string, attached at the top point via "pin to target" constraint to an animated object. (string constraints are SOP level, fed to DOP node, with "pin to target" constraint done within the sop solver "forces" subnet) Sim follows the object, and i can break the "pin to target" constraint itself via the vellumconstraintproperty node, set to the group with the top point. I tried various ways to group the centre point of the line, and keyframe another vellumconstraintproperty node, but it doesn't work. Can anyone enlighten me on the proper way to break string constraint points in a keyframe-able way instead of just using stretch stress? Thank you very much in advance!
  5. Vellum Cloth Eyelit

    HEY everyone, I'm trying to recreate a metal eyelit in a cloth and I am going about this using simple cloth. so far I have a pretty nice working file but my cloth starts wrinkling almost right next to the eyelit. I am trying to make a fall off on the outside radius of the metal eyelit so the fabric has more integrity to it around the eyelit/is more stiff and then gets more flowy further away from the eyelit. I am also seeing intersections with the cloth and the eyelit ( I think I need to model the eyelit properly so it doesn't intersect from frame 0 into the cloth or it wont recognise that it's a collider) Anyway I'm very, very new to houdini and have come from c4d so I was wandering if you guys could take a look at the HIP file I've uploaded and tell me if I have the correct setup and how I can make the cloth around the eyelits more stiff so all wrinkles eventually falloff to 0 before it hits the eyelit. Using vellum simple cloth btw with attach to geo constraint. Cheers eyelit.hip
  6. Hi, please see the attached Cinema 4D video of what I am trying to replicate in Houdini. I want to interactively position an object on a surface using handles. I made some progress with the Creep SOP, but it has several limitations: it deforms the source object, which I don't want it doesn't have viewport handles, so I have to edit the node parameters, which is undesirable (I have a lot of objects to manually position, so I want to make it as easy as possible) it doesn't work with polygonal objects I don't mind using VEX or an Attribute VOP to achieve this. Thanks. Slide_on_Surface.mp4
  7. Hello! I'm messing around with bullet constraint networks and I can't figure out how to connect a bunch of points to a single point... basically one source point and multiple paths from it towards each packed piece. Connect adjacent node doesn't have this behaviour. The idea is to connect a fractured packed geo with many points/parts to a non fractured packed geo that has just 1 point/part. I know this will requre some kind of wrangle & coding is not my strong point :| ... any help woud be appreciated! Thank you for your time I appreciate it! Attatched a simple scene, it's just missing the 2nd constraint network. polyline_constaint.hipnc
  8. Hello I just followed tutorial about Bendint Metal using hard constraint. (www.youtube.com/watch?v=38RhntxXcMI) and had some problems with setup hard constraint and need your help TT In my scene, I setup my hard constraint like left screenshot(red lines). and just like the tutorial, write vex codes for make hard constraint where middle of each constraints. This is guide geometry of constraints in dopnet. Left side is the tutorirals constraint one and right is mine. Modeling is different(I create my modeling my own), but I don't think It makes those difference in constraint. I set up Rest length option same with tutorial but what are those additional constraint points ?? I think those points causes difference with the tutorial so I need some helps to get rid of them. How can I get rid off them ? Sorry for my English TT
  9. Glue RBD on Vellum

    Hey guys, is there way to do this? I have to rip an envelope and it have that wax sealing it. It rips just where the wax is. The wax doesn't break but it have to influence the vellum in some way. Anyway, just a simple test with RBD and Vellum interacting would be awesome. Thx
  10. Hi, At this point I need a new pair of eyes on this one and maybe a new brain. I have a simple test scene with a rbd ball smashing a wall, the wall is holding together with ConeTwist constraint. I then use the good old sop solver to 'removeprim' the constraints when the angle is larger than X. I can see the Angle attribute in the spreadsheet and all, but for whatever reason (I know it's a very simple one), the constraint bend but don't break! If someone as a few minutes to spare and take a look it would be much appreciated. Sorry if I sound sarcastic but I'm getting frustrated by my own stupidity! coneTwist_test.hipnc
  11. Difficulty breaking hard constraint

    Hi guys, I'm having trouble breaking my hard constraint. I'm currently working on a metal destruction and upon impact my constraint doesn't break eventhough i give a treshold in which I want my constraint to break. I'm using a wrangle with: if (f@distance > ch("break_me")){ removeprim(0,@primnum,0); } but my hard constraint stay together. Thanks
  12. Spring Constraint

    Error - Glue constraint references unknown object Would really mean a lot if someone could take a few minutes to look at this file. I was trying to recreate richardlord's spring constraint thingy, but had trouble even beginning to get it to work in the first place. I think there's some changes in constraints from 15-16 (im working in 16). I should have the name attribute matched up to all my constraints and all my objects as the same, but for some reason I get an error with, 'unknown object'. I thought it may have been that the constraint was looking for @rest? Not sure. Very new to creating attributes that get used in dops, I appreciate any insight. springConstraint.hipnc
  13. vellum hair break [SOLVED]

    Hi, exploring vellum i'm trying to break an hair geo by enabling the "break threshold" option in the "vellum constraint" SOP. I must be missing something on the constraint workflow of vellum because it has no effect at all on the sim :'( I'd be curious to know if any of you managed it ! Thanks vellum_hair_break.hipnc
  14. Vellum Cloth and String weld

    Hi guys, I'm playing around with vellum but something is bothering me: I want to attach a string to a cloth but I cannot do it if they are 2 different vellum objects in DOPs The example file will be much clearer than what I write but the question is: Does all the vellum objects need to be merged to build a constraint network, am I using the wrong method meaning I should create the constraints in another way ? Thanks for you help ! cloth_and_string_01.hipnc
  15. i am personally interested in setting up wire constriant using old apply relationships method, i am curious about the efficency and other aspects compared to constriant network, did someone already test it in some big projects, could you please share the experience, thanks a lot!!!
  16. Hi all, Is it possible to constrain packed RBD objects to the static deforming or animated obj? In TP its work by default without any problems, but in houdini I cant find solution. Thanks!
  17. Hi, I have been searching for a solution to this RBD problem for a few days now and can't seem to get this to work fully. I attached a scene file with some descriptions inside to help explain. The basic notion here is to dynamically create spring constraints when some packed rbd cubes get close enough to a collision sphere that is at the origin. I can't seem to get the constraints to work unless they are created/exist on frame one. I create them inside a sopnet in the dopnet and use a sop solver to get them into the constraint network setup. Haven't tried creating constraints like this before so might be totally wrong in this approach. This setup works as long as all constraints are there on frame one, and then in the sop solver I set a high strength if the cube is close enough to the sphere, which semi locks the cube to the contact point on the sphere, which is what I want. However if you change the search radius on the wrangle node in the sopnet so that only the closest cubes to the sphere have constraints on frame one, then only those constraints ever evaluate. Any help sorting this out would be appreciated. I couldn't find anything in other posts to help with this. Most posts I saw were about dynamically deleting constraints and not creating them after the sim is going. Thanks E RBD_CONSTRAINT_TESTING_CLEAN_V2.hip
  18. Hi Guys, I'm trying to create a constraint network for simulating Car Suspensions, but with no results. I just need a simple "spring effect" between Body and Wheels (please find a video example attached). How I can do it? Any suggestion will be really appreciated. Thank you! I've attached a simple file test I'm working on. Car Example.mp4 Cartest.hip
  19. Well, I went out into the RBD Constraint Forest Unprepared, and now I am lost in the woods. Any help would be appreciated. I'm trying to do something that should be fairly simple, and most likely is, but I don't have the combination to the Houdini lock to get the setup to work. In the example file I have an rbd box that has 10 faces per side that have been made into unique faces. They have glue constraints holding them together and are a rbdPacked object in my dopnet. There is a low rez smoke sim that pushes this rbd box into a collision sphere that is above it, and when the geometry collides with the sphere, some of the glue constraints start to break. All I wish to do is apply either a gravity force or a popForce to these rbd pieces that have lost their Glue constraint. I want the main chunk of the rbd box that still has a bunch of pieces glued together to keep on moving with no gravity or popforce. I might be trying to go about this the complete "wrong" way since I have very little experience with Glue constraints, But I see data in the geometry spreadsheet while in the dop net called ConstraintGeometry and this has a primitive group called "broken" which contains the glue constraints that have been broken due to collision. I would think I would want to try finding out which rbd piece that broken constraint belongs to and then use that to create an "applyGravity" group of rbd pieces so that I can do what I want to do. I just don't know how to do this in dops. Is this something that needs to be done in a sopSolver or geometry wrangle or....? I'm not to familiar with how to read data from the ConstraintGeometry and apply it to the Geometry data. When I middle click over my rbdsolver, it shows the main rbdpackedobj1 with Geometry and then CosntraintGeometry below it. They are like separate entities and I'm not sure the best way to get access to both in one node, if this is even the way to do it.? For example if I change a geometry wrangle to point to "ConstraintGeometry" instead of the default "Geometry", I can then read and manipulate data on the ConstraintGeometry, but then don't have access to the main rbd "Geometry" that I am use to normally working with. Like everything in Houdini, there are probably dozens of ways to go about this, I tried about 20 yesterday, without ever getting one to fully work. I ran out of search phrase ideas to try throwing at google after about the 6th hour of searching. Maybe using some of those copyData and applyData nodes would get the ConstraintGeometry data onto the Geometry stream so they can both be read in one wrangle or maybe that too is a completely wrong direction to take. I don't want to speculate any further since you could try things for a week and not get it to work if it just isn't the right approach. I love Houdini for its vastness and unbelievable tool set, but man, it can destroy you if you don't know how to do what you want to do, and can't articulate it well enough for a search string.! Thanks for any help. E rbd_constraints_v01.hip
  20. Is it possible to use at point group from sop level, to constraint points in a dop (wire sim) with the "SBD Pin Constraint", instead of manually typing in all the points, that has to be "Constrained Points"?
  21. Hello, i am currently working on my final student projet where i make a plane crash with Houdini. I base the workflow of this project around the RIGIDS III tutorial by Steven Knipping. Everything is working fine until i bring in a simple glue constraint, and when the simulation gets activated at a said frame the simulation simply does not happen. It works when i disconnect/disable the constraint. I already tried to unpack the alembics upon importation with the alembic node but that didnt change anything. What is weird is that everything was working fine when i used the model given with the course. I haven't really found anything that helped me online, so hopefully one of you can help me with this issue, i would appreciate it A LOT. I will attach the files down below. Thank you ! plane_sim.rar
  22. FEM in 16.5

    Hi. Im trying to constraint points on a FEM object in H16.5 but cant select any points to constraint. Have anyone had this issue? I use the shelf tools, then do the following. 1- Constrain points to target 2- try to select objevct i vewiport, dont work, have to select it in Node menu/dop menu 3-cant select any of the points on my object in dops. In H16 i animated the Geo in sops, then added constraints to some points in Dops, then it worked. But i intalled 16.5 today, and i cant select any points. Im kind of lost. Ive read about upodates in H16.5 put i could not find any answer. Let me know if i didnt explain this good enough. SOLVED: i had to use a visibility node in sops to mark my tetras. fem_poins_issue.hiplc
  23. Hi, In Max we use a lot of link constraints when it comes to technical Animation. E.g. a roboterarm grabs and moves something from position A to position B and during the movement the object that is being moved is constraint to the roboarm. I attached a Video to make it more clear. What is a nice way to do something like that in Houdini ? I looked at the Rivet Object but I could´t find a way to animate it. I would be thankful for some input. Jon Link_Constraint.flv
  24. Hey all, Apologize in advance for the noobiness, but this must be the right place where to ask. I'm trying to instance more than one Spotlight to a deforming geometry. What I've done so far was scattering points over a mocap and riveting a spotlight on a single point. My question is: Is it possible to procedurally instancing spotlights on every single point, possibly following the normals of the deforming geo? Might sound a tricky question so that's my .hip file attached {{ dnw5.hip }} Much love
×