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Found 641 results

  1. Hi, So I am thinking about creating the velocity in node geo1 and move the points in node geo2. The problem is, I want to change the velocity each frame so i have a solver node in geo1. let's call it solver1. when i want to move points in geo2, i created another solver node, solver2. I am thinking about simply reading the velocity in solver1 and use it in solver2, like using getattrib. However, I am not sure at each time frame what is the order of execution. How can I ensure that at each time frame solver1 is executed before solver2? Thanks!
  2. Hello. I have an array attribute and I need to figure out min values among all first, second, third, etc elements of arrays. If I were about to know the exact length of array (let's say 3) I would do this... iterate insider forloop "distances" append values to three new arrays and find min values with min function. min(distancesone[0]), min(distancestwo[1]), min(distancesthree[2])...... My problem is that I don't know the exact number of array and min() is useless as long as I can't manually create arrays of specific number elements. So the question is how can I figure put the min value among distances[0] elements, then [1], [2] and so on... Thank you.
  3. Detail VEX Function does not working

    Hi, I have two controller-nulls, with the same parameters. In one of them, parameters are animated. I created an attribute from "Del_Sys_Moving" parameter, and then, I want to switch between static and animated attributes values. Then, I want to use this attribute value in pathdeform node as "curve_posoffset" parameter, by using the "detail function". But, it does not work Also, I have tried to write "details" (not "detail") with backtick, for HScript, but it also not working. What I do wrong? How can I write the value of detail attribute from one node, to parameter of another node? Thank you! And sorry for my English
  4. Hi I have a basic scene in which I have animated the rest length of vellum objects using a SOP solver. I then switch from the wrangle back to the 'dop geometry' at a certain frame. What I would really like to do is switch to the 'dop_geometry' when the restlength reaches a certain length. However I'm not sure how to reference this in an expression on the switch. Any help would be very much appreciated. Thanks Restlength_Switch.hipl
  5. Hi guys/girls, so I built this voronoi scale set-up for a mesh (see attached file) and would like to transfer uvs from the original base mesh to the scales, I've tried several different look-up methods but nothing has worked thus far. I managed to bother Jonah Friedman on linkedIn who did a similar set-up on a chameleon spot for psyop (see video link attached below) and he said that he'd done that in fabric engine and to copy the uvs from the original mesh he did a closest point lookup, but sadly that has not worked thus far for me. The final model will be texture painted in substance painter. Any help from a some uv and texturing wizard would be much appreciated! OH, AND I THINK I HAD SET THE VIEWPORT STATE TO MANUAL REFRESH, JUST IN CASE SOMEONE DIDN'T REALIZE! TRIPS ME UP SOMETIMES. Psyop scale set-up voronoi_scales_RnD_06_odforce.hip
  6. Free video tutorial can be watched at any of these websites: Fendra Fx Vimeo Side Fx Project file can be purchased at Gumroad here: https://gumroad.com/davidtorno?sort=newest
  7. vellum sin force

    How to add sine force field to vellum? thanks!
  8. Hi guys, I need to find all points, near each point, in a certain radius. So I tried these codes: int np[] = nearpoints(0, @P, chf("Max_Radius")); i@NearPoints = len(np); Is there any simpler function for this situation? Thanks for helping. Find Near Points_01.hip
  9. I want to copy point one attribute to another attribute. But it seems not correct. I have point attribute @N , @tangnetv. In vex , i tried @N=@tanget. I hope @N and @tanget be same direction. But it seems something wrong direction. I've attached houdini file. What happen is this ? tes.hiplc
  10. Curveu Noise

    i have a curve that is deforming and the topology is changing. So i cant use rest attribute if i use a noise function it is point dependent and so gradually the curveu noise changes on my curve. How can i add a noise to the curveu attribute independent of the points? I want it to be static, somehow based on the curveu attribute so that it sticks on my curve no matter the deformation. I can do this manually with a ramp parameter of course but i want it to be procedural with a seed value. Essentially i want to do exactly what the ramp parameter does - remapping the curveu attribute - but using a noise Any tips?
  11. Hi, I was wondering if could be possible to define a struct in the outer code of the snippet and export this data for each class' items of a geometry (per point, prims, etc...)? Below is an example of a Wrangle running over Points with the "outer code" from wrangle/attribvop/snippet exposed as a parameter VEXpression: myStruct example = {someRandomNumber, someRandomVector, ...}; // How to export "example" for each point? Outer Code: struct myStruct { float someFloat; vector someVector; // and some other variables } Is it even possible? Where Houdini could store those pieces of information? The spreadsheet could only represent default data types right? Am I missing something? Thank you!
  12. what's the Geometry traversal's application in Houdini? best regards.
  13. Free video tutorial can be watched at any of these websites: Fendra Fx Vimeo Side Fx Project file can be purchased at Gumroad here: https://gumroad.com/davidtorno?sort=newest
  14. why my code doesn't work as it said in doc? it says unexpected identifier
  15. Poisson Disk Sampling Help

    Hi guys and girls, I have this condensation on bottle shot I'm working and would love to create a poisson disk distribution with a uniform sample of points based on the area of the triangles in the mesh. I've been looking at the papers written about this but its a liittle bit technical for me at this time. I'm hoping some could maybe look at my file and point me in the right direction to use vex to create this algorithm. Thanks much in advance. poisson_on_bottle_setup.hip
  16. Free video tutorial can be watched at any of these websites: Fendra Fx Vimeo Side Fx Project file can be purchased at Gumroad here: https://gumroad.com/davidtorno?sort=newest
  17. Hello everyone.. so I'm trying to group primitives fed by letters from an attribute.. so what I want is a group for primitives that hold "A" string and a group for primitives that hold "B" string and a group for primitives that hold "C" string any idea how to ?
  18. Delete Boundary primitives

    Hi guys , I'm trying to delete the boundary primitives of a grid after using convert line node as shown in the pictures below with the help of VEX for procedurally deleting the boundary primitives of a grid . Thanks in Advance.
  19. Hi. I was trying to use some "maketransform vex code" I've seen in a tutorial in order to scale objects along custom axis. But kind of lost and don't know how to apply the code properly. Any help? The file is included. I was thinking maybt it's better to apply some matrix that will bring every object to the world origin, then apply scale and then invert "back to origin" translation matrix so that the objects come to their local spaces... but don't know how do it in vex. maketransform.hipnc
  20. Extract/Apply transforms and rotations

    Hey ppl! I'm trying to extract transform, scale and rotation from one geometry and apply it to another with VEX. In my case I'm extracting from a grid (2nd input) and applying to heightfield (1st input) which only takes Y rotation. Help me figure it out? Thanks! transform.hipnc
  21. Hello, I have a sim set up using flip objects with geo copied to points. I want to be able to delete 5% of my points every frame after a specific frame, so there is a gradual deletion. I referenced this post which triggers from frame 1. https://forums.odforce.net/topic/29024-delete-5-of-points-every-frame/ Can I achieve that same setup, but trigger it from a specific frame number, rather than from frame 1? I'm a beginner and still getting my head around vex. Any help is appreciated. Thanks.
  22. while writing a line of vex function in a parameter field, the help card appears every time you drop down a "comma" or end "quote marks" for the next item on the function. However this behavior doesn't occur while writing the same function inside an attribute wrangle node, it appears only once after dropping down the first parenthesis and to call it again i have to go to the beginning (right after the first parenthesis) - press space and then back-space is it possible to get the help card on demand inside the Attribute wrangle window (i am not asking about the F1 help/ docs call) OR the same behavior as we get in the parameter window? - very helpful for vex-noobs thanks plenty in advance! d.
  23. I am struggling a bit to build a setup that can bake DPdu/dv onto the points/vertex of an object. I am trying to then pass this info onto a series of scattered points across the surface that I am caching before passing to another application. The issue is I cannot seem to calculate DPdu for instance on a surface in a SOP network. Apparently Du(), primduv(), etc all don't work in sops and only in shading networks. I have got something kind of working using the polyframe node. But the issue is it isn't doing exactly what i need, specifically it seems to be normalizing the vectors. It says there is an option to orthogolize the output tangentu,tangentv vectors but does seem to be doing that wether that option is checked or not. Basically I have a box for instance with UDims uv's assigned, and several of the sides have the uvs rotated 45 degrees and zoomed in. When i view the resulting tangentu/tangentv coming out of the polyframe node they seem to pick up the correct orientation, and are indeed rotated 45 degrees on the facts that are rotated. However the vectors all seem to be normalized to be 1 in size. So I cannot then look at the vector size to get texel density/scale for the surface. So basically is there a way to get the tangentu/v on a surface from the uv's coming in for an object, such that I can figure out the texel density and at the same time the orientation of the uv's on the surface? I guess if i could get the scale factor for u or v in world space that would be also enough. I mean basically I just want the rare unnormalized DPdu values for a piece of geometry that I can then assign to points I scatter across the surface as an attribute? I have banged my head against this for a day now, so really appreciate any insights the geniuses on this forum might have, that would save me another day or so of trying to figure this out.
  24. Free video tutorial can be watched at any of these websites: Fendra Fx Vimeo SideFx Project file can be purchased at Gumroad here: https://gumroad.com/davidtorno?sort=newest
  25. I have Subnet node name is "subnet1". In "subnet1" i have ROP node.The same name as subnet is "subnet1". When i change my subnet name change the my ROP name too. How to write in "On Name Change" python ? Thank you.