Welcome to od|forum

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.

Search the Community: Showing results for tags 'groups'.

More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • General
    • Lounge/General chat
    • Education
    • Jobs
  • Houdini
    • General Houdini Questions
    • Effects
    • Modeling
    • Animation & Rigging
    • Lighting & Rendering
    • Compositing
    • Games
  • 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 12 results

  1. So, i tried something from scratch for the first time, albeit very simple... almost there! That being said i did got stuck up... 1. SOFT SELECTION GROUP: i am trying to apply some animation to a bunch of lines through a pointvop. i want the animation to be limited to all the points but the ones at the ends of the lines, i create a group of those points... it works,- but could be better if i could make the animation blend to the static points at the end. 2. FADING TRAILS: At the end i added a bunch of trails with some lag and or jiggle. i am coloring them with the width attribute through an 'attribute create' node. Is there a way to make each trails less opaque than the previous. (if this can't do the job, any other tips?) 3. NOOB VOP NETWORK CRITIQUE: I am pretty sure my vop network is far from efficient, i would appreciate if anyone has some tips to make it more logical/ efficient. I hope i was able to explain myself. (i have attached a screenshot for reference) d.
  2. Hi, need some help. After using duplicate node. I marked "Create Output Groups" for the copies as: zone$CY Now I have some groups inside primitives spreadsheet named group:zone1 | group:zone2 | group:zone3..etc, with values 0 or 1. I need to create a new intenger attribute named "zone" only with the number of the zone, and then finally delete the groups. all this with attribute wrangle. Thanks in advance.
  3. Looking at the Geometry Spreadsheet. A Group SOP creates an attribute like "group:foo": I can easily access that group "attribute" in a Wrangle like so: i@myvalue = @group_foo; QUESTION: How do I access that group attribute on parameters that requires an attribute name? For example, in a Color SOP's Random from Attribute: Or on a Delete SOP's Filter Expression: Although I know that I could just type the group name on the group field. I'm just curious if there's a way to access the Groups data as "Attributes". Particularly, I'm asking because I want to access Groups as an "Attribute" in the Enable Solver DOP without actually creating an actual attribute to represent the group: Hopefully I'm just missing or forgetting the proper syntax.. P.S. The Enable Solver could use an option where it can check for existing groups. I'll probably send an RFE
  4. Hi, a concrete slab ( box with size 3, 0.2, 1.5) after a voronoi fracture, I'm with prim groups: piece0 piece1 piece2 ... I'd like to select a few of them (pieces at the border of the slab) I know how to do it manually in the viewport / component groups / enable group selection or press 9 but how can I use this in a procedural way ? Like in a group node, with a bounding box ? It will only group the primitives, is there a way to extend the selection to connected geo ? must be possible..
  5. Hey all, Im about to make a RBD emitter for some typography. I'd Like to know if there is a way to reference the number of a nodes name (e.g. blast1, blast2, blast3) within an expression (something like @textindex=@blastNUMBER??) to save me manually typing which group I would like to isolate? Cheers Jim
  6. Hi all, Ok, so this is slightly embarrassing but I can't figure out how to do a 'per primitive' extrude on a surface. Basically, I have a grid that I'm turning into hexagons, and I'd like to extrude/inset each primitive or 'cell' individually... Is there an obvious option I'm missing here? I am assuming there is an expression I can drop into the group sop to achieve this? Unfortunately my expression knowledge is limited & I'm not sure I'm trawling the help for the correct terms! :/ Thanks in advance for any help or suggestions! extrude_example.hip
  7. Hello, I encountered problem when I tried to dynamically change groups for cloth constraints. I've tried SBD Pin Constraint to attach cloth to animated geometry. As goal object I used geometry with same topology but animated one. When I am not changing pin group it works fine, but I need to change constraints during simulation. But then it goes funky, it seems as it cannot correctly assign constrained point to goal point. Next thing I tried was to use Cloth Attach Constraint node which works almost fine, but during updating pin group points slide over goal object. Could you check attached file? I am not sure what I am doing wrong. Basically what I want to do is to attach points of cloth to animated geometry and then release it. Is there some other way to achieve that? Thanks, Juraj jt_update_groups.hipnc
  8. I have a character that I want to use in a crowd setup. This should be simple, but how do I apply different materials (head, shirt and trousers) to the coresponding name groups (or name attributes) that I created before the agent bake process, with style sheets in houdini 15? I could not find much in the docs about this. Any help would be welcome.
  9. I have a part with many primitive groups and it would be good to be able to visualise the groups in the viewport instead of having to manually find what refers to what by stumbling around with the delete sop. Any ideas? Ok so there's a way of doing this by using the select tool and choosing groups in the context menu above, a list then appears to the right and everything is color coded.
  10. Hi, I have a question regarding using alembic format to export an animated l-system to maya. I was able to succesfully export my l-system (which is a flower) to maya, however i was wondering how would i perserve groups from houdini. Since when i export it to maya the l-system has no materials and is exported out as a single mesh AND applying materials to the leaves, stem, blossom would be very tedious face by face. What is the best way to approach this ? I have a deadline coming up very soon and ANY help would be really, kindly greatly appreciated !!! Kind Regards, Vaco
  11. Hi. I got node. DA with two group parameters. Two group class menus, one for each group parameter. There are two classes to pick: - points - primitives When I change selection type in viewport (points=>primis or vice-versa) I would like to have correct class set on my node. Q1. How to do that? Q2. Can I extract some data from for example selector to see what was picked up? Thanks.
  12. Hi all, I'm a creative C++ coder playing with Houdini - pretty beginner but with some understanding of what's going on. I've cached a flip simulation as BGEO sequence, and I'm having trouble adding custom attributes to the points which are dependent on initial position of the point in respect to the initial shape. E.g. let's say I want to melt a teapot, and I want to to use different triangulation parameters for the body and the spout. I.e. I want to mark the spout as "bodypart"==1 and the body as "bodypart"==2 and create groups based on that. This I know how to do: 1. Load the teapot in a geo node. 2. Cookie the spout with a simple shape hilighting the spout area, do points from volume, attribcreate and assign 1 for bodypart 3. repeat for other parts etc. 4. create a flip fluid out of these points and solve it 5. cache the resulting simulation as a BGEO sequence 6. load the BGEO seq, and all of my points still have the custom attributes, and I can use those for meshing and various other visualisations. This works perfectly and does exactly what I need. However problem with this, is if I decide to add/change body parts, I need to re-run the flip solver which makes no sense since the bodypart attrib has no effect on the simulation. Doing this attrib create before the flipsolver makes sense for things like color and viscosity, but it doesn't make sense for attributes which don't affect the sim I think. what I would like to do is: 1. Load a mesh and select different parts of that mesh and assign only attributes which are essential to the flip solver (e.g. Cd, viscosity etc). 2. create a flip fluid out of these points and solve it 3. cache the resulting simulation as a BGEO sequence containing only attributes which are essential to the flip solver 4. load the BGEO seq, and assign new attributes, which I will use for meshing and various other visualisations. If I use the same method (i.e. volume intersections) on the BGEO sequence, it understandably applies the volume intersection every frame, and so the attributes are re-applied every frame to the points inside the volume, and don't move with the points. What I really need is something like "at frame 1, do the cookie and attrib creation, and then maintain those attributes throughout the BGEO sequence" but I can't figure out how to do that in Houdini. Any tips welcome! P.S. I have 'reduce' set to off in my flip solver.