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Found 36 results

  1. Hello, I'm starting to learn Houdini and following a course from PluralSight named Architectural Destruction, the final result is pretty much the same I need in my project, an exploding building with many different layers and materials. All the previous steps worked like a charm, however when I try to break one part of the building using a force I created, it behaves different from the tutorial, even configuring the constraints. Instead of exploding the area, like in the tutorial, it looks to blow the entire building at once, indepedent of the size or magnitude of the force, as the example below: Generating the force I have an attribVOP configured this way: And inside the DOPnet I have a geometryVOP this way: I tried to change the constants to reach the result, but with no success at all, is there any way to create some kind of falloff or decay for the force? How can I proceed? Any hints or ideas of what is going on? Thank you very much! Any kind of help is very appreciated !
  2. Glue Constraint Gravity

    I have been spending some time creating and destroying a building in Houdini but am currently hung up on a constraints problem. In my hip file I have my procedural building, I fracture it, and send the pieces to be constrained together. I haven't meticulously created the constraints yet, I just wanted to get everything in and working first. When I run the rbd sim a ball crashes through the building and blows the middle part of the building away but the top part of the building just sits there floating in the air. Not exactly sure what I'm doing wrong here, if anyone can point me in the right direction I would greatly appreciate it! The hip file has a top level control node to cache everything for you to quickly test skyscraper_destruction.hipnc
  3. Wire constrained to two objects

    Hi! Having some problem here with wires eheh. I'm struggling for some time now to achieve something that first seemed so simple, but i'm really lost now! I'm animating an old style phone, with a cable quite rigid, and i just want to constrain one end to the phone (animated) and the other end to the base (fixed). I have it half working, but i can't figure out how to keep the cable semi-rigid... It just "break" were the wire points are constrained. And want the cable to "leave" the base nearly rigid, then deform, and be rigid again when joining the phone... Keeping the base and phone's orientations... (hope it makes sense, sorry for my english) I've search a lot, read and downloaded examples from tokeru wiki, tested all the constraints, but i must be missing something important... It works perfectly with gluetoanimation when one end is contrained and the other is free, but as soon as i try to make the base's end to be also constrained, it doesn't works... Does anyone have some kind of directions? (You can see in the attached video that the base is "breaking" while the other end seems good...) tel_cable.mp4
  4. Hi all, I'm trying to understand how to manipulate the constraint strength so I can art direct a simulation. Figured setting the strength in a group in a SOP Solver on the Constraint Network was the way... but can't get a simple example working. Simple test attached... idea was strength reduced if the constraints are within the bounding box of the group... figure it might be that the constraints aren't moving in the SOP solver, although with my test it changes the values immediately even not in the group.. so getting lost. Any advice/help/direction, very much appreciate. Constraint_Strength_Test.hipnc
  5. Hi folks, I am following Steven Knipping's tutorial Rigids II and have some behaviour here which I do not understand and can't solve somehow... You'll see the issue in the attached gif (some of the cluster in the upper part of the hole) I have basically the same settings as in his videos, but it seems that somehow the constraints are going to stick together after they are broken. At least they should break because of the metaball force (which I am using) and the corresponding huge hole inside the building and everything should collapse and not stay like in the gif. First I thought the "Overwrite with SOP" parameter on the constraint network would be the issue (which I then changed to $SF==1), but it didn't help. I am using H16.5.323. Thanks for any ideas and suggestions Cheers Dominik
  6. Hi! This is what I did: I made a cool sim with wires and constraints, it works all fine but I decided that I wanted those colored polylines that are drawn by the sim for the constraints. So I created another geo node and object merged the "Visualization" geo from the Constraints Network, It worked! but with a little problem, If I scrub through the animation timeline sometimes I get the "static" state of the constraints, this can be solved If I just scrub a little more near the frame that has the problem, sadly it happens again in another frame (randomly) I guess that my trick is a little dirty and Houdini doesn't like it. Is there anyway I can import this visualization geo as seen inside the DOP Network? Here is my file, It's a little messy (weird experimentation) so sorry for that. Just Press Play and you should see the problem. DynamicWireConstraints_personal.hipnc Houdini 16.5 NC
  7. Hi! Ok here is the thing, I understand almost everything about the file BUT there is a thing that is driving me crazy and is happening in the "SOP Solver" inside the DOP Network, there is a merging sop using the constraints from the previous frame and adding new ones that are created by the distance between the points of the wires, the weird thing is that there is no accumulation of constraints happening, what I expected from this merging is that the constraints number will increase over time but for some reason they are deleted and recalculated in the next frame. So I tried a few thing with the file and found that if I "by pass" the wrangle node that animates the "pin" constraints things go as I expected (constraints accumulate over time and the for that reason the sim slowdown) WHY!! Even if didn't bypass the node and only change the range in the fit operation calculated in the wrangle from (... 1,0) to (... 0,0) making it "0" all the time killing the animation the sim work as before and deletes the constraints (no accumulation) but if I delete the whole fit operation and replace it with a value of "0" directly the expected accumulation goes on (you can check this if you run the sim being inside the SOP Solver). So maybe someone can help me to understand why this is happening, I think the Accumulation of Constraints prims is the correct behavior (at least is what I expected) but the sim runs smoothly if the constraints dissapear so... WHY Here is the example File (I modified it a little bit: Geo name and a red sticky next to the node you want to bypass) HOUDINI NC 16.5 Wire_constraint_network_v02_modified.hipnc
  8. Duplo Bear via Bullet Constraints

    Here is a breakdown of how I made this bear made out of duplo blocks: The video isn't super comprehensive, I mainly cover setting up the constraints in SOPs, though I briefly touch on some other parts too. But the hip file is available to pick apart! Thanks! duplo_bear.zip
  9. hi, how can we constraint a pre fractured object WHICH has been glued together to the ground plane ? i mean constraining a constraint? where and how should we make the constraints ? should we scatter some points withing the region bottom to the fractured object ? and do the constraints ? have no idea how constraining between constraints should happen :| thanks a lot ..
  10. Hi, I have a question about APPLY RELATIONSHIP. When I use it with PIN constraint it works but I want to use HINGE in stead (to avoid that the spheres start to rotate), but APPLY RELATIONSHIP doesn't accept it (warning:wrong type), why is this? What is the workaround then? Any tips?
  11. Hey there odforce! Right now I'm trying to do a destruction simulation on a spaceship that I made, and I'm running into a problem that I can't seem to figure out. If anyone is familiar with Steven Knipping's Rigids III, the general setup is based off his approach. Here's some quick info on what I'm doing: * I'm simulating the spaceship destruction with bullet/packed primitives * These packed prims are a mixture between voronoi shattered pieces and unshattered geo pieces * Even when the spaceship is standing still, forces on the constraint prims will reach infinity once simulation begins * In DOPS, I've made a SOP solver that breaks my hard constraints once it reaches a certain force threshold, and since things are reaching infinity, it's basically just destroying all my hard constraints within a few frames Here's the ship: Here's the constraints using connect adjacent pieces from surface points with default values: After a few frames of simulation, it turns to dust =/ In dops, force is shown to reach inf and breaks the constraints based off my attrib wrangle which says... f@superHighNum = 100000000; if(f@force > f@cat_hard_break_force && f@cat_hard_break_force < f@superHighNum){ @group_broken = 1; } where f@cat_hard_break_force is the force threshold that I define I tried countering this behavior by adding the f@superHighNum, but it looks like forces gradually reach infinity, so it still breaks... Has anyone encountered this sort of issue before? If so, what might cause these forces to reach infinity? Here's a few things I've tried: * Cleaning up the mesh and fusing points before connect adjacent pieces * Setting rest length to zero * Blasting funky looking constraints before simulation * Trying a bunch of different settings on connect adjacent pieces when generating the constraints * Simulating with glue constraints to see if forces still reached inf (they do not reach infinity with glue) * Increasing the constraint force mixing parameter * The RBD physical properties are at default values Also be sure to check out Steven's tutorials because they're really awesome. I couldn't find his e-mail to ask about it, but perhaps you guys might have some ideas? Any thoughts, theories, ideas, would be greatly appreciated, thank you for your time! - Tyler ssGainz_v011.hiplc
  12. Constraining wires to Cached Geometry

    Hello everybody. I'm bringing in a cached character animation and cached curves from Maya as an Alembic cache. I've split the character and my hair curves apart and created a DOP with wire solver where I can successfully simulate the curves colliding with the characters body and falling endlessly into space. I'm now trying to create constraints to constrain my Zero cvs for my wires to my scalp points on my cached character which is in the DOP as a staticobject. The hair curves have a group already with all the 0 cvs and the static object has a group for the scalp points. I'm trying to find a simple way to constrain these two groups together. I've tried using an sbdpinconstraint but it wants all of the constrained points and goal points to be in order so that it can constrain them to one another in that order. Is there a node or method by which I can constrain these two groups of points to one another intuitively based on distance. I'm also considering caching my hair curves in maya so that I can just glueToAnim but I'll still need to know how to constrain things. I'm a bit new to Houdini, hope you guys can help cheers.
  13. Hello, In Houdini 16 is there a way to add a spring constraint to a Coth object. Want to simulate rope/cable anchors. A standard pin constraint with Soft doesn't feel like the cloth is tied down by rope and would also like to have that Max length parameter. Alternatively, if I can use a Wire simulation to be used as a spring constraint that would also work. However, my attempts at doing this have been disappointing. Wire sim would either become the dominate force by pulling the cloth down like a lead weight or the cloth with pull the wire like taffy, And large values were used in the wire setting to no avail. Any thoughts? -Thanks
  14. I have two separate stacks of geo made using copySOP's, i am trying to get them to interact with each other. They do interact with each other but the constrains only effect one model, i can switch them in the merge but its only ever one that holds together, the other falls apart instantly no matter what the glue strength is. Ive put photos below and attached the scene file with the model that needs referencing in. New to Houdini so any help or advise would be greatly appreciated! Thanks PlateSimulationTest001.hipnc plate.obj
  15. I am trying to animate an engine using chops and constraints. I manage to get something quiet close but it isn't accurate(cheat) My main issue is that i cannot find how to use a "look at" in conjunction with some restriction to force the tip of the arm to slide along the Y axis. I tried many other solution as well as trigonometry(which i am not very good at) which i gave up on. i also tried with bones but again my knowledge is close to none in houdini and i wasn't able to restrict bones I wish to achieve the real thing with your help Thank you piston.hip
  16. I have one packed primitive object which consists of several pieces of geo merged together. At sop level (before it is set to become a packed primitive) I have created a core group and an outer group. I would like the core group (the red group) to remained glued only to itself and the outer group(the green group) to be spring constrained to the inner group and itself. The trick is how can I do this without manually blasting the undesired glue connections or using the delete by color method? The reason being that I have very complex geo which is very close together. I have a simple test set up .hip attached. The real which geo I am actually working on it extremely full and chaotic. Thanks! packed_relationship_04.hip
  17. Ok.. so .. How do I setup the wheels of a car that follow a null but retain independent rotation? parenting uses all the transforms types ( SRT)
  18. Hey, I spent a while prepping and adding to a model house for a destruction project but I'm having a lot of trouble gluing everything together. I can get the components of the house to glue together no problem (e.g. the windows, the walls, the bricks etc). But what I really want to learn is how to glue each of the fractured components to eachother. What I mean is that my house just falls apart, the bricks dont stay attached to the wall, the glass windows don't stay in their frames the roof shingles dont stay on the roof. I'm really hitting a wall here (no pun intended). Can anyone lend me a hand in figuring out how to approach this? The picture is my destruction model. Each component (roof, walls, etc) has its own constraint network but they arent glued to eachother so when I sim the pieces just pop off.
  19. Hi everyone, I'm brand new to Houdini 15.5 as of October 2016. I have been learning a great deal in a short time but there's some things I would very much like to figure out for something I'm working on. I'd like to know how to create an effect where a membrane, eg a cell wall, is being broken apart when particles collide with it. I know how to do fractures based on particle collisions and I assume it's a similar process. I'm just not sure how to get that tearing effect you might expect when seeing a membrane lose its surface constraint. I appreciate any help from some of you more expert wizards out there. Thanks in advance!
  20. F.E.M. stretch using constraints

    Hi everyone! I am currently learning F.E.M. (after avoiding it for years ) and I would like to pin few points of a solid object to an animated position. I saw there is a number of methods (using targetP, targetV, ...) but I was unable to make them work.. The Follow Target shelf tool on Solid shelf works weird, it asks only for the constrained object (my solid object), then for the constrained points (I select them on the solid object), but that's all! It doesn't ask for the object to actually follow! For the sake of simplicity - I created this simple test with two animated spheres and I would like the solid object between them to be stretched (the points of the solid object, that intersect with the spheres should be constrained to the animation of the spheres). I deleted all the "non-working" failed constrained nodes to make it clean. Can anyone point me in the right direction? Big thanks for any help! FEM_stretch_test_V01.hipnc
  21. I am building out a Big Bang collision. I have a very large sphere that I use as the all encompassing universe. This is a static object. It is the Universe Sphere. I then have an RBD that I set the "center" parameter/attribute to the Universe sphere center channel. This sphere serves as the Big Bang, which has been fractured via Vonorni. I use a smaller sphere, whose "center" parameter is also set to the Universe Sphere center channel, as the initiator of the collision. I set the radius up for the Spheres. The Initiator Sphere is key framed with a Uniform Scale of 0 and then the very next frame it is set to 1. The size of this instantaneous expansion sets the velocity. I set the mass of the Initiator Sphere way up and I use a Position node to keep this Sphere for the most part locked down. I set bounce to 0, rotational spin to 0, and friction to 0. Over all, these settings, for the most part, keep the Initiator Sphere locked at the center of the Universe Sphere. However, I am getting a very slight wobble, before the Initiator Sphere settled down into a perfect center in reference to the Universe Sphere. What I am asking is what is the most efficient way to stop the wobble and lock the Initiator Sphere to the center of the Universe Sphere. I have looked at Constraints, however, the universe sphere is a static object, not an RBD, so I am thinking constraints will not work. I am looking for a very uniform collision across all out ward moving vectors, much like a uniform nuclear detonation. Any help would be much appreciated.
  22. Hi Houdini people, Is there a way to do constraint for RBD solver for RBD fractured object? I have to do rigid body simulation to interact with cloth, so cone twist/glue/Hard constraint are definitely not the options since they are all work for bullet solver. I am still new to this. Please help. Thanks
  23. Hey there, I am currently trying to simulate a (single) falling fir-branch like the ones you can see in this image: I would like to use a wire solver for that, but I am having a hard time to make the needles stick to the branch. How would you go about that? Desired setup: * branch as wire obejct (soft body behavior when colliding) * needles as wire object attached to the branch (soft body behaviour as well) * gravity in place, falling fir-branch, colliding with a ground plane. I tried the "Attach wires to surface" shelftool, but that attaches the selected wire points only to existing points on the branch-geo (which is low res, with just a few points). I would like the needles to be independent of the branch geo so that I can have a rather lowres branch geo (tube, less subdivs), and lots of needles. I would like to attach them like it is possible with folicles in maya, having them stick wherever they are on the surface, not having them stick to one of the input points on the fir branche geo. Using the point attribute "pintoanimation" or "gluetoanimation" also does not work. Doing so, the needles jitter around as soon as they are not in line with a points of the underlying branch geo. Do you guys know any solution for that? Thanks in advance for your time and help! Cheers, Philipp
  24. Hey guys. I'm trying to figure out a destruction setup for things like fences, wooden frames, plywood walls (that thin stuff thats really easy to put a hole in accidentally) etc. The part I'm stuck on at the moment is how to mimic things that are nailed together. Specifically, how to set it up so that when the fence/frame/whatever is hit by something, it doesn't just break apart, but instead just becomes a slight bit loosened, causing it to wobble a bit and fall over slightly. I realize that explanation probably makes little to no sense, so I've included two reference images. One depicts the effect that would happen for an entire fence, the other is for a single beam. I've got an example scene that uses the Cone Twist Constraint. It it gets me part way there, but is obviously way to static, and just stops suddenly. What I would like would be some subtle wobbling, as well as the beam the rotate down abit (to mimic the photo with the horse). I had the idea of using a Glue constraint with a bit of stretch. Problem is, I have no idea how to get a glue constraint to stretch (or if its even possible) and I couldn't find anything on Google about it either . Is anyone able to point me in the right direction for figuring this out? I'm still struggling to understand constraints so any guidance would be extremely helpful Nailed_Wood.hipnc
  25. I started a thread a few weeks ago about using scattering and Voronoi points to create clusters from multiple objects. That thread is here: Clustering without fracturing? Luckily, that was solved after much confusion. However, now that I have that rendered with a few other stuff thrown in, I got curious about secondary fragmentation using those same clusters. The problem I'm running into is when I'm in DOPs and I add a voronoifractureconfigureobject. When there is collision's, there are no fracturing. But, If I un-cluster the bricks and constraints, the bricks will fracture as expected. I attached a photo and my file to the thread :D. Thanks! building_frag.hiplc
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