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Found 28 results

  1. Hello I am trying to do something really simple and I am finding it to be quite hard. I am trying to rotate a box so that it carries momentum and settles down naturally as if it had mass. I have included a .hip file where I have attempted to do this manually but it is not the best. I am struggling to get the animation editor to behave and I have to keep closing and reopening Houdini as the Animation editor and the viewport are not marrying together. If anyone knows why this is or if there is a better way of doing this, (I have tried motion fx (spring)/chops but it failed miserably) I would be very appreciative. I have come a long way in this wonderful program but for some reason the animation editor feels really clunky in comparison with the rest of the program and I don't know if it's something I am doing wrong. Thanks dampened animation.hip
  2. Does anyone know if there's a way to bring in automation channels from MIDI (eg. volume, pan, fx controls) from MIDI files (not realtime)? I thought it maybe the Control tab in MIDI In but I've had no luck. Thanks, Simon
  3. I have a simple audio react animation that is conneceted to a CHOP network, just a few polygons with a simple extrude based on an audio trigger. However I want the objects to extrude sequentially; on the first audio trigger primitive 0 will extrude, then on the second prim 1 will extrude, so on and so forth, but have it be sequential and based on the audio trigger from chops. I attached a simple hip file, any help would be greatly appreciated Chops_sequential_ODFORCE.hip
  4. Hey all I'm quite new to houdini so please bare with me. Is there a way to use an audio output from chops to change the position of a particles? Can I do that by using a pop vop? If so, how can I import my chops output in there and add it to the position of my particles? Is there maybe a better solution for that? Thank you!
  5. Hey, I was hoping someone could help me out with a CHOPS set up I'm stuck on. I'm looking for a channel to continuesly increase over time at a set rate, but with added intervales? That may no make sense so I have set up a scene to decirbe it. The image below show the white line which is what I'm after. Its a mix of the red (contast increasing value) with the sine wave pink line, but only the positve values, which then get added to the red line. Sorry if that's confussing, CHOPS is confussing! Any help would be really apprciated! Chops_Increase_01.hip
  6. Hi everyone, I'm trying to figure out a way I can offset a keyframe by a channel value. For example, I want to animate the uniform scale on a sphere but I want to be able to control the start frame of the animation by a channel value. I'm sure there is a way you could do this in CHOPS, but I'm not very comfortable using CHOPS, and thought there must be a simpler way of doing this! Thanks in advance
  7. Hi all, I've been trying to figure out how to create a linear ripple effect (i.e. rather than have a single point as the source, I'd like to source it from a line/selected edge/group of points, so that it travels across a surface like a wave.) Now, of course, at a basic level the 'waveform' SOP node performs this exact operation - *However* it can only generate a single wave at a time, and it lacks the signature 'decay' of the ripple over time. I had the idea of using the wave operation in CHOPS using a sine wave with decay on it, however any changes to the amplitude are applied across the whole waveform, rather than 'at birth'. So it doesn't create a dying wave, it just scales down the whole waveform. (see image). Any ideas on how to achieve this? (just as an FYI, eventually I'd like to control the decay length with an animatable paramater & creation/scale of the ripple from CHOPS with a trigger.) It seems like it should be super easy - Maybe I'm just having a bit of a mental block! :/ Any mind jogging greatly appreciated!
  8. Hi ladies and gentlemen, boys and girls, I have a job to create a kaleidoscope animation. I'm just learning how a Kaleidoscope works in real life and time is limited. Has anyone ever worked on such a project and can give tips on how to get started and maybe some math behind how it works? I've attached a video I found that has this effect created by buck (starting at about 16 seconds in). Any help here would be much appreciated really. Thanks in advance. Sherwin Williams - Kaleidoscope-SD.mp4
  9. I am trying to make some hda's to help speed up and distribute my mocap cleaning process, however when I make an HDA in CHOPS I get an error saying the sub-network has no output, and when I go to edit operator type properties, sure enough the outputs are greyed out. Anyone have an idea on how to fix this?
  10. Hi... I'm looking to attempt some image manipulation using CHOP nodes. Having used the Image CHOP to access the individual pixel data I'm lost on the best way to Export it back to COP context. I'm guessing I could do it with the VopCop2Gen COP, but thought their might be a better (easier) way? Cheers!
  11. Hello everyone, I wanted to transfer my animation from DOPs to SOP level, but I need to have a baked Curve. I managed to make a transfer between CHOPS > SOP using dynamics and export in CHOPS, but when I click Edit Data Channels and then Fit Panel > Copy to Export Destination (9 channels), I got a message "Status: 0 channels copied." The connection between CHOPS and SOP still works, I have a curve in Motionfx editor but I can't transfer it to Animation Editor and delete CHOP Network. Please Help.
  12. I am trying to work with Mocap data that I have recorded in Vicon Blade. I have an FBX of the solving setup that I have imported into Houdini and I have been able to work with it and get the setup where I want it to be, but I am running into an issue with file size. I am currently sitting at 189MB and I am pretty sure that about 95% of that is keyframe data. Unfortunately when I start working with the file it explodes in my memory and is becoming unwieldy. I am talking in the 25gb range. The Motion Capture data has placed a keyframe at every frame for all of the bones, which is definitely overkill. Is there any way of automatically reducing keyframes in Houdini? I have seen the tool in some other packages, but I am trying to figure out how to do it here. If there isn't a built in way to do it, is there any way I can delete keys in CHOPS, because I could see writing a VEX expression for doing it. Something along the lines of calculating the slopes and if the slope from one keyframe to the next is below a certain margin, delete. Or hell, I could just check concavity at each keyframe and only keep the ones where it changes, but I need to know if there is a way to delete the keyframes.
  13. Hi, I have a simulation and I want to filter points position after simulation is finished to remove jitter. But during simulation I am deleting geometry which is not visible (so that simulation runs quicker). So I cannot filter P attribute based on ptnum. Is there some option to run chops by id attribute like in Trail node Attribute to match? So that if point does not exist his value will be set to 0 or last available value instead of using attributes of another point. Thanks, Juraj
  14. Hey all, Anyone know how to reference video footage as a texture within Houdini? I know you can only input image sequences using CHOPs but even this stage is having me scratch my head. I have no experience in CHops so if anyone give me a few pointers of how to load in a sequence and then have this referenced as a 'diffuse' for a shader or whatever, it would be greatly appreciated. Cheers.
  15. Hi, Is it possible to get the channels of multiple objects in the chops context using one node? Perhaps importing bundles, or defining a list nodes? Thanks!
  16. Hello everyone, I would like to introduce my new Houdini training, "Houdini Rocket Ship". The idea behind this training was to create a project that will take the viewer through a variety of aspects of Houdini without making the project overly complex or technical. As long as you have a basic understanding of Houdini you should be able to follow the training Over the course of this project we will cover a whole range of topics which include Procedural modelling, Polygonal modelling, Environment Generation, Cloud modelling, CHOPs, RBD, Constraints Network, Smoke Simulation, Materials, Lighting using HDRI, setting up Takes, Rendering and Final composite in After Effects. There is currently a one week discount on the training series of $25. The offer will last till 17th October 2015. Trailer Final Animation for further information kindly click on the link given below http://www.rohandalvi.net/rocket
  17. First of all, I want to tell you what end result I want so you can solve my scene file or suggest other easier way of doing it. I want to get the transformations of these rbd dominos to object level. My first approach was to simulate rbd fractured objects then use dynamics chop to get that data and export it to object level but it got some problems. My second approach was to "get point data" from dops and do some matrix magic in VOPSOP with points and import that data through geometry CHOP so it can get exported to object level grid's transformation. I have tried to use orient attribute to my advantage but objects behave weirdly. Their positions are wrong. This is good exercise for you to use SOPs, DOPs and CHOPs interconnectively. You can see my file with both approaches, check out these nodes and tell me what am I doing wrong? I just want to apply the boxes domino data to grids in object level. Thanks! dynamics orient.hip
  18. I'm trying to bring in a midi channel but it doesnt show anything in the Motion FX view (Houdini 14). Is there anything I need to specify on the midinIn node? (If I open the midi file in something like quicktime I can hear something so the midi file should be fine). Also playing back audio is very jittery unless I set it to "Maintain realtime playback, possibly skipping frames". Is there a way to get smoother audio playback whilst playing back every frame? Even if I have nothing in my scene its still jittery...
  19. Hi guys, Sorry if this seems like a noob question but I just can't figure it out somehow. I need to apply some CHOPs function to ONLY the Z-axis. But I can't seem to only export the Z-axis in the channel node. I know its definately something simple which I might have overlooked. Anyone could help me with this issue Thanks! -Darren
  20. I am able to resample/ rearrange points along a curve shaped primitive by a ratio (0,0.1,..,1) attribute. using a look up chop for that. how do I do that same operation on a bunch of separate prims? loaded in chops I get a saw like curve representing all ratios from all prims in one curve, but what I like to have is one curve ranging from 0 to 1 in a linear fashion (representing just "one" ratio) so that I could change that shape with a spline chop. does this make sense? thanks in advance -sebastian edit: attached a hip resample_by_attribute.hip
  21. I'm trying to export rotation for a couple of IK bones from chops. I've put down a MERGE node in CHOPS and bussed all the IK chops there. But the problem is it only cooks when I MM click on it. So I go inside chops, MM on it and go back out to my bones and presto, the IK rotations show in orange bkg in the rotation fields... But if I move the IK bone again, the merge node remains uncooked until I dive back in and MM click on it again. Funny thing if I enable export on a simple InverseKin it works properly.... but I need more than just one bone. Am I doing something wrong... or what's the best way to bounce all the IK rotations back to the bones. Thanks
  22. Hi. I'm looking for a way to write a bunch of channels (CH_Channel objects) to .bclip file. CH_Channel class has save() method, but it writes data in (.chn format). I found a clchn and clcp utilities shipped with houdini. But it seems they can only convert .bclip files to .chn while i need backward conversion. UPDATE: As often happens, i found an answer right after i post this question To save channels in bclip we need to create CL_Clip object, populate it with CL_Track objects, sample each CH_Channels and write samples to CL_Track. Then CL_Clip.save() saves data to file.
  23. i am comparing the rest distance between 2 nulls in chops with the object node. and i want to compare it against the animated distance. so i thought to put down a vopchop and just do some "if then". so connecting the 2 distances into the vopchop, but now inside the vopchop how to do i grab each one of them? so i can compare them? and export some value that i can use? thanks.
  24. Hello, i'm relatively new to Houdini and have been working on creating animations using 100% procedural audio. I have done the great tutorials of Peter Quint and I have some basic stuff happening. Super fun and I'm loving it; hope to post some WIPs soon. My question is related to separating out various instruments. I have struggled and struggled with the pitch SOP with very little success. My goal is to have different 'instruments' (say voice, or guitar etc.) drive specific objects/channels but i'm having a really hard time 'pulling apart' the music. Are there any tutorials or known 'best techniques' for doing this? Obviously, if i had the source tracks pre-mix down that would be ideal, and i've started to poke at some music software that has this for CERTAIN tracks, but most commercial music is not available that way; i'm stuck w/ already mixed .mp3 and .flac. ANY help greatly appreciated here, thanks in advance, jsunandmax
  25. Hi everyone. I try to do some kind of flocking bird effects where al the birds are offset in animation with instance objects. Now i have setup a simple scene with just some tubes with a sin expression on the translate Y which i want to offset using chops.just for testing but i cant figure out what i do wrong. I think its a simple fix but i dont have that much of an experience with chops. anyone? thnx alot ChopHelp.hip