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Found 60 results

  1. 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
  2. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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!!!
  8. 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!
  9. 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
  10. 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
  11. 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
  12. 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"?
  13. 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
  14. 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
  15. 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
  16. 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
  17. I'm pretty new to Houdini and I'm not sure whats the best way to approach this effect. Right now I have a thin cylinder I am using for the string and I converted it to organic tissue in the shelf. then I have a big soft body that I also converted to organic tissue, and placed it on a rotating platform. All of that works great and looks nice when it deforms. But I'm not sure how to attach the rope to the soft body so that it will begin to wrap around it. I tried using a SBD spring and that had no effect. Then I tried using the Stich cloth tool from the shelf. That worked great in "hard" mode, but the two soft bodies stopped colliding. Then I tried constraining the rope to a rigid body, and the constraining that to the bog soft body, it worked but the rigid body kept dragging everything around randomly. I attached my scene of what I have so far. Thanks! rope.hip
  18. Constraint RBD to Cloth (or Grains)

    Hello guys, How can I attach a rigid body object to a piece of cloth? I'm a bit lost on this. I tried cloth and also pbd with no success, now I have no idea on what i should try. There's a file attached (using grains). It's a starting point if anyone can give it a try. Cheers - Alvaro rbd.to.grains.v1a.hiplc
  19. So i have this sim and i would like to dampen or even remove the movement in the Y axis since it makes the concrete look light and weightless. I was trying geometry wrangle and anchor nodes, (not really sure how to use either), i wonder if there is a place where i can simply put a simple VEX line like @v.y = @v.y*0.25 or something similar. Can someone point me in the right direction on where can i do that and where should i plug such node in case there is a way. untitled.mov here is the Dopnet right now
  20. Hi everyone! I'm relatively new to Houdini, and I came across a tutorial which explained the bullet solver for H13. I am trying to recreate the effect that he got at 53:15, where primitives were deleted from the constraint network when a force over a certain threshold was applied. tutorial: As I understand, the SOP solver was changed in H14, and I therefore don't have the object merge node that he has. I downloaded the example HIP file and copied his node into my own project and managed to get it working, however I'd like to know how it actually works, rather than just copying and pasting! The data that the node is bringing in, is as follows: `stamps("..", "DATAPATH", chsop("relnode") + ":Relationships/" + chs(chsop("relnode") + "/relname") + "/" + chs(chsop("relnode") + "/relationship/dataname") + "/Geometry")` This isn't like anything I've come across so far in houdini - if anyone knows what this means, and could explain it I'd be very grateful! Best, Stephen
  21. Grains - Disable Constraint Averaging

    I posted this on the SideFX forum but haven't had any response so I thought i'd try my luck here: I'm getting some unbalanced forces when using grains, its the same problem as described in the grains masterclass around 32:50. As Jeff says the solution is to disable constraint averaging and then insure all the internal forces add up to 1. I've done this but I still have an imbalance.. I wanted to check which forces are meant to add up to 1, in the video it implies that Internal Collisions + Clumping + Explicit Constraints = 1. However in the help document it mentions that Friction with Particles should be included as well. So should I set Friction with Particles, Internal Collisions, Clumping and Explicit Constraints to 0.25? (
  22. Hi .. I am trying to follow along with a tutorial that goes over wire constraints and pins. I cant get it to work properly. If anyone has any brilliant ideas ... let me know. here is a hip ... wires_3.hip
  23. Hi .. I am trying to follow along with a tutorial that goes over wire constraints and pins. I cant get it to work properly. If anyone has any brilliant ideas ... let me know. here is a hip ... wires_3.hip
  24. Hi I am trying to understand the applyrel node a bit more, and more specifically I am trying to add constraints on the fly by adding points into a group on sop level. half way kind of there but as always with Houdini running into a few issues. If anyone could possible take a look at my scene and point me in the right direction it would be most appreciated. wirescon.hip
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