Jump to content

Search the Community

Showing results for tags 'attribute'.



More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • General
    • Lounge/General chat
    • Education
    • Jobs
  • Houdini
    • General Houdini Questions
    • Effects
    • Modeling
    • Animation & Rigging
    • Lighting & Rendering
    • Compositing
    • Games
    • Tools (HDA's etc.)
  • Coders Corner
    • HDK : Houdini Development Kit
    • Scripting
    • Shaders
  • Art and Challenges
    • Finished Work
    • Work in Progress
    • VFX Challenge
    • Effects Challenge Archive
  • Systems and Other Applications
    • Other 3d Packages
    • Operating Systems
    • Hardware
    • Pipeline
  • od|force
    • Feedback, Suggestions, Bugs

Found 97 results

  1. hello, i have a curve in 3d space with an organic shape and i want to resample it so it becomes jagged but maintaining its features. So i was thinking i should compare the tangent value of each point with its next one and if the difference is big it means the curve is changing direction so i keep that point. If there is no big change in direction i remove points. But i have no idea how to implement this in Vop or Vex, i am new to Houdini. Any ideas?
  2. Hey there, i was wondering if any one to could me figure out how to achieve this affect, this person was kind enough to share this setup but I'm no closer to achieving the same result. I've created the Cd attribute, ive attched my working hip file if it's of any use. Any help would be most appreciated VELLUM_ANIMATED_CD.hiplc
  3. Hi, is it possible to write/read a point attribute to/from an external text(or any other format) file?
  4. Dear community, I am working on a little particle system that I need some help with and I hope that you can help me out somehow: I am emitting particles from points A. These particles are attracted by another pointcloud B via POP Attract, with the attraction type set to points. So far so good. My question is now: How can I vary the attraction force inside pointcloud B for each point? Is that possible? I've been looking into and reading the docs, of course, but all to no avail. Does anybody have an idea on how to solve this issue, meaning giving the points in pointcloud B varying attraction forces? Is there an attribute that I have to apply on pointcloud B, that POP attract could use? Best wishes and merry christmas and Chanukka, Nicolas
  5. Hello everyone ! I can't figure out how to copy the attribute pscale (from a wrangle) onto a sphere... I am sure I am missing something because it should be straightforward see attached figure Thanks and sorry for the low level question
  6. Hi everyone! I need to do a local rotation using an Attribute VOP for individual points of a grid and just can't get my head around this... If I e.g. rotate along the Z-axis and THEN rotate along the Y-axis it again rotates over the world's Y - not the shifted local Y-axis with a new orientation after i rotated over Z. What I basically need is taking the newly oriented "local" axis into account - the Y-axis should always point upwards from the upside of a cube. No matter how the cube is oriented. I hope you guys know what I mean... i attached an image to clarify. Also I attached a very simple example with 3 Attribute VOPs for rotation over each axis. No matter how the cube is oriented, it always rotates over world-axis. Maybe somebody can point me in the right direction? testrotation.hiplc
  7. Mass in General

    Hi people, I'm trying out Vellum in Houdini and I was wondering how mass works. I noticed that the mass is a point attribute. That said, if I want to know the total mass of the object, do I need calculate the sum of all the points ? Thank you.
  8. Hey, I'm trying to get this stick to points constraint to update every frame so I can have this cloth sort of peel down over time. Thought setting 'create constraints' to 'each frame' would make it work but doesn't work. Also tested using a value instead of an attribute which also doesn't work. Any pointers greatly appreciated. Attribute_Val_Cd.hipnc
  9. Hello, friends! I`ve got some issues when started coding in vex with the default float type attribute creation, so i got a habit to always set the attribute type, even in calculations, to prevent the possibility of attribute type errors. Like this for example: v@direction = v@initial_position - v@P; It works fine, and i am really comfortable with it, but I wonder is it correct in the meaning of 1) Good programming style. 2) VEX language work under the hood - maybe VEX is re-declaring the attributes again, when they are used in this way. Thank you!
  10. Hi, I've tried to cache out .obj files which have the same naming as their import counterparts. I managed to write their original name into a string detail attribute (for example "one200_300-236-58_korpus.obj") - next I thought I could reference those attributes in a filecache node ($HIP/`detail("filecache1",attribute1,0)`) but nothing happens - I just get a file called 0 without any .obj Does someone know whats wrong with my setup? Thank you
  11. Hi, I am currently creating a simulation with flip fluids that are affected by a vortex force. I need the velocity/lift attributes to be animated independently throughout the simulation, though no matter how I set the settings for either the sop geometry, or vortex force operator, the values will not change throughout the simulation. What is the proper method for animating these attributes for use in dops? Thank you,
  12. Import attribute into VOPS

    So I started watching this excellent tutorial about creating a spiderweb and got 3 minutes in.... https://www.youtube.com/watch?v=LFkzD9cgxek It's over my head with the coding at the moment so I thought I would try to create the same with SOPs and a bit of VOPs. I got pretty far pretty quick, and everything works so far (some dodgy maths, and weird values that work), but I am stuck on the VOPs bit. I want to randomise the rotations for the spar angles, I have them setup as primitive attributes, each one having a different number. I can get the attribute into VOPs (I think), but I'm pretty stuck at how to implement the randomisation per piece/attribute. Any help appreciated. HIP file attached. ) spiderweb_v002.hip
  13. Hi, for some reason, I can't use a custom integer attribute like (i@a=@Frame;) to drive offset(x) it a 'Mountain SOP' but if I assign @Frame it works just fine. I also tried it in a 'Timeshift' node with the similar result. Am I missing something? q2.hipnc
  14. Ok so just when I thought I had got my head around for each loops, I am struggling to get a custom attribute into a transform. The attribute is certainly seen by the copy to points node. and when I try to detail it in the transform, it justs gives back a zero. I've tried by including the transform in the for each loop, with a block begin fetch input etc. Makes no difference. (Using the spare input and -1 tag instead of the "../iteration". I've tried all combinations of cases @ signs, $ signs and whatever else. The "global attributes" colour and the scale nodes work fine. effector_v003.hip
  15. Hi) Can I somehow get the maximum(and the minimum) value of an attribute in VEX? I want to use them in a FIT function.
  16. Recently I started learning VEX, but now and then I hit a wall. In this case I can't find the answer on my own. What I'm trying so solve here, is to read the pscale from the closest point. //PSCALE @pscale = random(@P);; //NEARPOINT string me = itoa(@ptnum); i@near = nearpoint(0,'!'+me,@P); //READ PSCALE FROM NEARPOINT @npt_pscale = point(0, "pscale",@near); Getting an attribute with the point function works fine in most cases, like with the @P or @Cd, but with pscale it gives me a value of 0.0. Not sure I this is the best method, or maybe I'm overlooked something. I really can use some help. nearpoint_pscale.hip
  17. Hi, Can I somehow attach a string variable to an attribute? I want to get something like @P."string" where instead of "string" there should be "x, y or z"
  18. Hello everyone, I am new to houdini, and I am trying to do something I think should be simple, but I can't wrap my head around how to set it up correctly so that it works. I want to transfer a point attribute from points generated on a source mesh, back onto set mesh or ideally into a redshift shader (RS_material) to control the opacity. I am trying to use the super cool tutorial below, and use the points generated to drive the reveal of a mesh through the use of the opacity channel in the redshift shader. I can't seem to understand how to set this up so that the parts that need to see each other can, and do I need to convert the attribute into something that can go from 0 - 1 and / black to white? I'm just a bit lost and im sure I over complicate things, so if anyone would please just point me in the right direction at least, it would be much appreciated. Like what is the general basic order I should of this? mesh - generate points - I can see the attribute in my geo-sheet but now what? attribute transfer I can't seem to use correctly Thank youuu !!!
  19. Hello there!! I want to select all the primitives that have a specific attribute - @P = 0 - and assign a specific color to them. How can I do this in VEX or with nodes? cheers!!
  20. Hello there!! I want to select all the primitives that have a specific attribute - @P = 0 - and assign a specific color to them. How can I do this in VEX or with nodes? cheers!!
  21. Hello peeps! I want to do something really simple but for some reason it isn't working… I have an attribute P1 that I want to use in the distance scale of my polyextrude. For some reason the extrusions are infinite. Does anybody know why is that? cheers! extrusion.hipnc
  22. Hi!! I have subdivided the primitives of an icosaedron. What I want is for each primitive, to select a random number of subdivisions (the small black triangles) , extrude them and control their density with an attribute. How can I do that?? POPULATION -HAPPINESS.hipnc
  23. I got this dla growth system, that generate new points from "old" points each frame. i want to instance different objects to the growing dla system. My problem is that when i use an attribute randomize "pscale" and "orient" to the growing points, that result that each point changes size for each frame, same goes for orient. Ive put my randomize in the solver, and was hope that would do it, but no luck. I guess i have to give each point a id attribute once its born, but not sure how to proceed. I went through entagmas toturial "Diffusion Limited Aggregation", that is where my dla/growth system is from, so im just going to give ewach point a randomize pscale and orient. Anyone know how to do this? dla_attribute_problem.hiplc
  24. Hi guys, I'm currently using the Bound node as part of modelling project and am looking to store the Y rotation created by the "Oriented Bounding Box" option. Is there a way to store these values or can you create the same rotation a different way after creating the bounding box? Any advice would be greatly appreciated! Cheers! -Henry
  25. Hi people, I got some problem with color loss in my balls array attached to point box. Everything is working as intended until I transform my array to RBD Object. In my scene I would like to have balls bounce around and collide with everything but I would like to have some materials and distribute them randomly on them as well. Everything is working but color is lost inside Assemble node at the end in Attribute Wrangle node called : add_name_attribute. I have no idea what happens but this node is making additional groups from my balls and in the end there are many groups which I don't need. All balls are turning grey in viewport as well. If you could have a look I would be grateful. ajz3d_randomize_materials2.hipnc
×