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Found 36 results

  1. 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
  2. FLIP - Hold tip of a snot?

    Hey guys, I'm working on this snot simulation and I need the top part of it to be "attached" to a nose. Any ideas on how to proceed? EDIT: Right now it's like this but I need to "constraint" it to a character. Thank's Alvaro Snot - v1-a.hipnc
  3. Constraint FEM

    Hello guys !!! Anybody know we have any possibility for constraint FEM like bullet ?
  4. Constraint Grains to Animation (targetP ?)

    Hey guys, how can I use this target pins option? I have an animation in sops and I need the grains to be constranited to that animation. I guess the targetP attribute shouldn't come from Sops but I can't find a way to make it in Dops beased on that Sop animation. Any tips? Thx
  5. Hi everyone, I made this setup to mix constraints between conetwist and glue, depending on angle value, i set the constraint_name in a sop solver plugged in the constraint network node, it works quite well but the resulting object is floating in the space... is anobody here can check my file and tell me what's going on!!!? apparently its not a subsanple or CFM, ERP issue ( i checked all this parameters and, nothing...) thx by advance, Best regards H TEST_PACKED_CONST_METAL_V002.hip
  6. Hi! I want to attach a geometry (some voronoi fragments in this case) to a moving/deformed mesh, i.e. I want to deform my base mesh freely and the voronoi fragments follow the deformations (Position and rotation or normals directions) without stretch it. I already try it with Point Vop but, how can I send the information of N directions to each voronoi fragment? If I send it with Cd looks like this: I animated the geometry with a mix and a group generated with color. I hope that someone know how to do this. Your feedback is welcomed and thanks so much!! Constraint Obj Test 01.hipnc
  7. Hi does anyone know how can I add a hard constraint between two or more particles ? exactly like RBD objects but it should be work for POP solver. I prefer do this via custom VEX codes for manipulating P or V. Thanks S
  8. Constraint RBD to animation

    Hey, how can I constraint an active RBD object to a static but animated one? For example I want that anchor to be constrained to that ring. A pin constraint just fixes it to a specific place. Tried wires but again this went crazy. So how can I get some realistic motion to his anchor? Also tried the oarent constraint which changes the constraint location from a static point in space to a goal object. Still no luck.
  9. Hi everyone! can't figure out why my cone twist constraint collpase at frame 2..., apparently this constraint dosen't care about restlength like other constraints... i tried all constraints, everything is just fine exept with this one, and cone-twist is exactly what i need.... I join a simple file based on a SideFX sample scene turned into what i need... thanks by advance Cheers! Twist-Const-Restlength.hip
  10. Hi, I’ve been approximating a hair simulation using wires (placed manually as NURBs curves), the idea is that I would constrain them to imported alembic skinned animated geometry and then export the result back to Maya. However, I’m having issues constraining the wires to the geometry. I’ve tried using an sbdconstraint and wireglueconstraint, but neither of these have any effect. The ideal solution would be the ability to simply constrain the roots of the wires to the closest point on the surface at bind time and then stick there regardless of where the alembic geometry ends up, as extracting the proper xforms for the head movement is another issue I’ve ran into so far. Any advice is helpful, Thanks, Sophie
  11. Constraints and animated geo

    Hi everyone, I was playing around with animated geometry and I encountered the following issue. I created this simple scene to show the problem I was getting with two ground planes, one of them is animated and on top of them I have a few boxes connected with a constraint to each other. The ground planes have a constraint to the objects touching them. I want the constraint of the boxes (red constraint) to start breaking when the ground plane moves. Right now I’m getting a weird behavior, where the constraint connecting the ground and the boxes is expanding (yellow constraint). When I remove the constraint connecting the boxes (red constraint), it seems to work fine but of course the boxes have not constraint and thats not exactly what I want. Here are two flipbooks and the hip file. Any help will be appreciated. rip_apart_constraint_01.hipnc constraint_issue_a.mov constraint_issue_b.mov
  12. Hi everyone. I'm making a mine themed rollercoaster and i'm wondering how to avoid keyframing animation. I thought about some kind of "rbd path slider constraint" that allows the minecarts to slide, accelerate downhill, slow down uphill and so on... but i can't find the way. Do you guys have any tip on how to implement something like that? Thanks!
  13. Hello I am creating a simulation where I have a sphere oscillate back and forth to rest. The sphere is moving but I also modeled a coil where I would like to constrain one end to the "wall" and the other end to the sphere so that it will squash and stretch. Right now the coil isn't moving. I have the file attached. Could someone show me how to do this please? I have looked online but haven't had luck finding something doing this directly. Thank you Single_Spring.hipnc
  14. Wire constraints to cloth object

    Hi guys I'm not able to figure out how to attach one of my wire object ends to a cloth object. I tried different constraints but none of them accept cloth object as goal object. So can you please look at this file and give me some advice. Thank you sail.hipnc
  15. Help with Constraints

    Hey guys, I have two quick questions. I'm trying to learn how to make constraint networks by hand. I've noticed that for some reason, when I define the strength of my constraint in sops using a wrangle sop, I only need relatively low values. However, if I delete strength attribute from my wrangle sop and control the strength in dops using the 'Glue Constraint Relationship" dop, the values needed to achieve the same effect suddenly become massive. For example, when I define the strength in sops, I only need a value of 10 to get the effect I want. However, controlling the strength in dops (no strength attribute defined in sops) require a strength of 100,000 to achieve the same outcome. I'm wondering why there is this massive difference between sops and dops. Also, say I wanted to add a second fracture object to the sim (unique the first one), with a constraint network of its own, whats the best way to go about bringing the second constraint network. From my understanding, adding a new object is as simple as adding a second RBD Packed Object dop, merging that with the original, and plugging the merge into the rbd solver. But with constraints it seems I would need a new constraint network dop and a new glue constraint relationship dop for every set of constraints. I'm just wondering if there a way to do it all through one constraint network dop and use multiple glue constraint relationship dops, similar to plugging multiple RBD objects into one RBD solver. constraints.hipnc
  16. cone_constraint_problem

    Hi, I am facing problem in cone twist constraint as you can see in my video that after hitting chunks or debris keep spinning....i don't know why......Can anybody tell me the reason and also the solution of problems... Thank you cone_constraint_prblm.m4v
  17. RBD make breakable question

    Hi, I'm struggling :/ I got a tall box (a building) I'm voronoi fracturing it. I got on big chunk at the top and many smaller at the bottom. I got a glue constraint network with some link deleted, so they can fall on the ground. Now I'd like the big chunk to be breakable so it can fracture when hitting the ground. So I use make breakable shelf tool and I would like to apply it to the big chunk only. There is a group field at the yop of the "voronoi fracture configure object", but I just can't manage to select the big chunk only. I should mention that I'm importing the fractured box as packed rbd. If I don't I have access to pieces in that group field, but with packed option, no more. There's a s@name attribut, but I can manage to use it :/ I'll make a hip file soon, but in the mean time, if someone knows where is my mistake or a solution...
  18. Exploding* Hi guys, Simple silly question, but I'm just wondering what I'm doing wrong. My hard constraints explode my with my geo. Thanks Example file below hardConExample.hip
  19. Create Glue Network In ForEach

    Hello everyone, I want to create a setup where a sphere breaks into 2 pieces and after a few frames those 2 pieces break into 3 smaller pieces. I am trying to create a glue network which would hold the secondary fracture until told but cant get my head around it.. I am doing the secondary fracture in a foreach node and that's where I'm thinking I need to do the glue network for it as well. I know its probably going to have a simple solution but I can't figure it out for quite long now. Please give me some ideas / examples. Thanks!
  20. Constrain to deforming static object

    I currently have a chain that i'm simulating using bullet and I would like to constrain the top of the chain so I can move this around and the chain will follow. I managed to get this working with the help of a scene that Pavel Pehlivanov posted on here (I can't find it now), but i'm getting strange results.. I've attached a hip to illustrate what I mean. Cheers anim_constraint_02.hip
  21. Hi! I have a hard time trying to break the glue constraint by sop force. Other constraints (like "hard" for example) work like a charm, but glue, even with VERY low strength, doesn't seem to even notice the force.. If I break the "wall" with a rbd collision object before the explosion force happens, it works. In the example please try to disable the rbd sphere and you will see, that it doesn't break by the explosion force on frame 10. I need the glue constraint to keep the pieces in place before the explosion. With just the hard constraint the aren't absolutely stationary, but they are moving a bit. Is there a way to keep them stationary just with the hard constraint? Thanks for any advice! glue_cns_sop_force_test_V01.hip
  22. Hello Everybody, I'm working on a Cloth Simulation in which I'd like to have a set of points to be Pin Constrained. But I'd like to change the Pinned point count over time, so it releases the constraints as the animation goes on. In the documentation on constraints I've found this: How to change the points that are constrained with the pin constraint during simulation By default, the Constrained Points list does not expect the points to change. However, there is a way to work around this and have the list freshly evaluated by DOPs on every frame. Right Click on the Pin Constraint node and select Allow Editing on Contents. Dive into the Pin Constraint node and select anchorobjpointgrouppos1. Change the Point Group parameter to Set Always. See the Anchor: Object Point Group Position help for more information on this node. http://www.sidefx.com/docs/houdini15.0/dyno/constraints So I've tried to do these steps but I couldn't get it to work for some reason. Maybe I'm missing something obvious. I've uploaded a very simple scene file in which I've grouped a set of points and animated the grouping bounding box. If it's no too much trouble would you guys mind taking a look at it and see if anyone can help me out with this issue? Any help or advice is much appreciated. Thanks for you time. Cheers, Laszlo cloth_animated_pinConstraint_v001.hip
  23. Constrain Hard Body sim to Wire sim?

    Hi all, I'm trying to set up a simulation where I shall have some rigid bodies stick to certain locations as much as possible (spring constraint maybe?) As you can see in the image I have a wire simulation. In that simulation the wire coils around some objects. I need these objects to remain within the coils. In the file provided there is geometry in obj > chromatin > NUCLEOSOME_CONSTRAINTS. This defines the point locations that I would like the pieces attached to. tldrl; How do I constrain an RBD fractured object to a certain location? constraints.zip
  24. EDIT The problem comes from the clusterpoint node which seems to add a duplicated piece name with no path: I am trying to do a bullet cluster sim. i am having a problem when doing the glue network. For some reason the connectadjacentpiece node doesn't want to compute on one of the cluster created. Whatever the number of cluster, there is always one cluster that will not be computed by the node. It seems that the problem isn't the foreach as when i try to select the problematic group and apply the connadjpiece outside the foreach, i still get no connection computed for that particular cluster in this particular example bullet_cluster.hipnc i added a partition to debug and see which cluster doesn't compute. You can change the cluster group and see that it works for all other cluster thank you for helping.
  25. Hi all, I've been trying to come up with a way to animate this https://youtu.be/gbSIBhFwQ4s?t=14s (ignore the high frequency jiggling movement) I have also attached a quite amazing MS paint schematic, but basically the animation is this: Have my DNA object following a curve (probably using the wonderful free tool https://www.orbolt.com/asset/animatrix::pathDeform::1.00) Other objects (histones) must come in and attach to specific points on that DNA. It then must coil up, all the while the histone pieces have to remain on exactly the same spot on the DNA. Finally the whole unit is coiled up nicely. I really do not know what way to approach this. I think I somehow need to get the histone pieces to be constrained by / attached to the curve, but I cannot find a way to do this (the rivet node seems way to cumbersome to be useful in this). Also, I cannot use dynamics :/ I have attached my current hip file which has the model and correctly coiled curve around the model. Any ideas would be most welcome as I'm quite stumped