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Found 41 results

  1. 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
  2. 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
  3. 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? (
  4. 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
  5. 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
  6. 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
  7. 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
  8. Constraint FEM

    Hello guys !!! Anybody know we have any possibility for constraint FEM like bullet ?
  9. 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
  10. 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
  11. 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
  12. 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
  13. 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.
  14. 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
  15. 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
  16. 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
  17. 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!
  18. 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
  19. 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
  20. 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
  21. 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
  22. 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...
  23. 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
  24. 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!
  25. 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
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