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Found 75 results

  1. how to import point (attribute VOP)

    Hello guys! Can U help me with small problem? I dont know how to import all of the points from scatter to attribvop (to get to an same gradient for all of them)?? Can u give me any advices? Thank you so much! hip. hile in attach how_to_import_all_points.hip
  2. Hello guys! Can U help me with small problem? I dont know how to import all of the points from scatter to attribvop (to get to an same gradient for all of them)?? Can u give me any advices? Thank you so much! hip. hile in attach how_to_import_all_points.hip
  3. 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?
  4. I'm running a for-each-connected loop, and need to rotate separate shape such that the largest face is down, for example the one marked L is the largest for the shape in the image. I have a theoretical idea, no clue how to implement it, and not sure if there is a faster or simpler way: (1) get the largest face (no idea how) (2) rotate till the normal of the largest face is facing down Again it's too theoretical, but if you have a way that would turn these flat on they largest face I'll be grateful
  5. Hi, I am just a newbie start learning Houdini. I am following Side FX's tutorials from very beginning. I was watching PWQUINT's 'Sop Solver' tutorial and having trouble. Tutorial show me using SOP Solver DOP to control attribute. So, I did create custom point attribute 'heat' and using for loop and if loop to increase 'heat' value frame by frame, also increase neighbor points' too. There is example file by PWQUIT but For Loop and If Loop vop was different and I tried to follow it with H17 but not working. I cannot find which part I missed. Thank you for reading my question. sopsolver_v001.hipnc
  6. Hi Guys I have a question for chramp function I moved RampValue using Addvop or Add function wrangle worked Look like repeat and vop worked clamp I don't know why two output is different (Left image uses Wrangle Node and the right image uses Vop Node) I think Solution is same , but result is different I wonder why this results chramp.hipnc
  7. Hey! Could someone help me understand this? I have noise going into the vector displacement of a principled shader. Why do I have change the amplitude of the noise in z-axis to affect the y (up/down) position? If I do the same at sop level I can just adjust the amplitude in the y value. I tried messing around with the transform vop, but I didn't get anything working. Thanks displace.hiplc
  8. 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
  9. I have searched the web for an example on how to use the Rounded Edge VOP http://www.sidefx.com/docs/houdini/nodes/vop/roundededge.html [www.sidefx.com] But was unsuccessful. I have a 3D model which is very reflective and has sharp edges. It looks dark in the environment, because the edges are too “perfect”. I want the edges to be rounded just enough to catch light and reflections. Can any one provide a simple example on a cube? thanks
  10. Lately I have been trying to wrap my head around transforming point positions with the use of matrices in VOPs. To do that, I tried the following: Lets assume I have 3 points with their position vectors A, B and C which come from an alembic and are constantly changing values. I use a time shift and set it to $F + 1, and extract the same points position vectors, which are now called D, E, F. Then I set A,B and C into a 3x3 matrix, transposing it (to get the vectors in columns instead of rows) and do the same with D, E, F. After all this, I multiplied the inverse of the matrix containing ABC with the one containing DEF (this was not inverted). The resulting matrix was multiplied with new Position inputs, but the resulting transformations didn't match the original ones... What am I doing wrong? Thank you.
  11. Noise in particles

    I sim a particle system, I want to put some nois after sim but Cd color is not baked at the particles, how can I baked it ? does Anybudy have clue ?
  12. HDA | VOP | NormalBias

    Longest Axis, Octant, Boxify, Hexplanar Mapping
  13. HDA | VOP | Bend

    Multi-context Bend.
  14. Noise in mat custom shader

    Hey guys, I'm struggling to understand some things in mat-level custom shading. Reading the manual and watching the masterclass didn't really help. I'm trying to use noise VOPs to drive the color (or displacement ...). But for example plugging a unified noise to basecolor yields no result (as most other noise VOPs, except bump noise). What am I getting wrong? Why do some nodes work, even though I'm plugging a float output in a vector input, and others don't? Thanks in advance. Cheers, Yulyan
  15. Hello All, I'm newer to Houdini, and working to jump into setting up some simple/fast solutions for wrapping particles around a mesh. Not sticking to the mesh, but flowing over. I'm a professional Nuke compositor with general experience in Maya, so will understand most terminology, but certainly completely new to Houdini, so open to all suggestions and breakdown's of the principles. The end goal is to drive a curl noise vortex up in Y, and place geo within the field that the noise will wrap and flow around. I have attached my test HIP file. I've been trying to combine this tutorial's use of the cross product and XYZ distance, with the VDB setup from Entagma's Curl Noise tutorial. Other than there being a good possibility I'm on the completely wrong path for this type of effect, it seems I may be confused on properly using the cross product in the VolumeVOP. The attached file doesn't touch properly adding or multiplying in the curl noise, because I want to correct my issue with the field to begin. Thank you all for your time, patience and help. My Best, Josh curl_noise_trailsTest_003.hipnc
  16. Hello, I was following a tutorial on how to create a sun in houdini, and I came across a technique used to keep advected points bound to the original surface where they were scattered from (in this case, a sphere). For the purpose of advecting the points, it was created a popnetwork with a curl noise affecting the velocity. To keep the points moving on the surface, the instructor did 2 things: -Turn the sphere into a mesh and convert it into a VDB. -Create a POP VOP, with a Volumesample and a Volumegradient, reading from the vdb converted sphere. After this, the gradient was inverted and multiplied by the output of the Volumesample node and added to the original positions, inputing into the new positions. This last point got me lost. The instructor referenced in some abstract drawings the utility of both this nodes, the Volumesample and Volumegradient and I tried to cross check with Sidefx's Houdini documentation but it didn't have that much info on the subject. Can some one briefly explain what is happening inside both this nodes, and their respective outputs? Thanks.
  17. Hello People, I have been trying to produce a Boolean value i.e. 0 or 1,So that i can use it as condition for my (IF Block) in pointvop. But whenever i am dividing Ptnum by 2 using the node modulo is always leave a value of 0. Help!!
  18. Possibly a stupid question. In older versions of Houdini there was access to the 'accel' attribute in vops. Where's it gone? I'm using H15.0.416
  19. Hey! I was looking at the scene found here: https://www.sidefx.com/forum/topic/26032/ I want to control the width of my wire with a ramp vop. This scene was created with an older version of houdini. When I try to recreate it with the updated nodes, it does not work. The original (which you can see in my scene) uses a vopsop and the add attribute, both of which are obsolete according to the manual . I tried recreating with the new nodes, but it does not work. Could some one let me know what's going on? Thanks! edit: for some reason the attached scene crashed for me when I downloaded and opened it. However, if you open houdini first then open the project (as opposed to opening file directly) it seems to work. line.hipnc
  20. Hey guys, it is possible to mirror noise within vops? Im trying to create some sort of fractal noise, for example on a grid of 4, having the same noise on each grid but flipped / mirrored. Thanks!
  21. Hello all, I'm modeling some tentacle creature and ran into a problem. I don't know how to stamp attribute into the VOP sop and use it to drive turbulent noise to randomise shapes for every copied tentacle. Then i want to copy that tactically geometry again and randomise tentacle shape and/or animation. I have tried to just bind stamp("../../copy" , "id", 0) into the vop and connect it to Offset of the Noise, but for some reason, Houdini just stuck in the loop. Please see .hip below. I feel like it is something obvious, but I cant see it. Please advice StampinVop.hip
  22. Volume mixing with VolumeVop

    Hello ! I made an explosion and I try to make it loop with Timeshift and volume mix nodes, Sadly I feels its too limited as the fading between the two volumes are quite obvious. Is there a way to mix volumes with a VolumeVOP ? The idea is to add simple 3d noise as the volume fade in and out. Thanks a lots
  23. Hi guys, I was hoping someone might have a clue here...I have a vop with an object running over an rbd simulation to activate pieces, the only problem is they seem to be becoming inactive again after being activated. So the basic question here is if there is a way to fix an attribute once it reaches a number (in this case 1) so it cant change back to 0? Cheers!
  24. Hi,I am working on crawling insects solver and actually i need your favour,there are some issues,actually particles leaving the surface after some level of accel...i dont understand why its happening... plz can u tell what i am doing wrong...and also any other suggestion is also welcomed...Thank you for your precious time PFA Nashrat Shahi test_v01.hip
  25. From SideFX' tutorials on UV Basics III, I understand that you can connect to an image brought in and edited in the /img context (via the null node, named OUT for example), and then reference it in other contexts, specifically the /mat context, via the syntax of op:/img/img1/OUT On the SideFX forums I got the suggestion of instead using op:/img/tex/OUT This is what I get. Actually, I get that whether I use “op:/img/tex/OUT” or the standard “op:/img/img1/OUT” Oddly, my material turns this light pink as opposed to the standard grey, either way, when I try to call in the texture from null node. I want to be able to edit my texture images with all kinds of colour corrections and procedural tools over in /img and then bring them in live into my shaders in /mat. What am I missing, or messing up?