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Found 47 results

  1. Hey magicians, Been getting crazy with wire solvers. I think the issue is because I get the points changing over time and the constraints go crazy. I've been reading that I need to create a id attribute with $PT to hold the value, tried that with no luck. Animation works fine until the number changes Any tip will be super helpful, thanks in advance.
  2. Hello, I have a feeling this is a common issue, but its a bit hard to explain / search for a solution. I've imported an animated alembic file, used unpack to get the points and put it through a trail node to get the point velocities, the problem is that the point count changes as some of the objects "disappear", so you get brief flicks of extreme velocity as the point IDs shuffle, I am curious about the method(s) for dealing with this problem.. Thank you
  3. hello guys. I am new Houdini user. I got a question about copy to point. I can't find out a way to get each sphere scale from 0-1 when every time it generated in this case. I need some help to know about the concept to make it happen please. thanks. here is the file link: copy to point file
  4. 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
  5. Hey all! I have a bunch of points travelling around, and I would like to create a new set of points, where each of them is orbiting around the given point, in the direction of the main point, I guess the image attached explains it a little better than words...just trying to do it with vex code cheers
  6. I'm trying to build out an idea for an HDA that would create a vine along a surface based on a find shortest path SOP and some controllers for where the start and end points would be to control how long the vine is. This is mostly intended to be a tool in a realtime engine with the idea that it would be cooked into a static mesh (so it doesnt need to animate). I have the main branch generating fine but I am attempting to create some branching points from the main curve to create child branches from this main branch. However, I'm fairly new to Houdini and kind of stumped where to go from here. Currently I'm scattering points from the main branch and attempting to drive them away from the main branch while following along the surface normal of the underlying mesh. I've got something really basic(just sending them out at a random vector direction and snapping them to the surface) but I feel as though this method doesnt give me any control. I thought about trying to make the branches use a find shortest path as well but Im not sure how to control where the start and end points would be procedurally, hence why I was trying to create curves along the surface normals in an attribute wrangle instead. I attached a .hip file for anyone willing to take a look. Thanks for any advice, I appreciate any pointers in understanding VEX better. IvyGrowing.hip
  7. Hello ! I'm struggling to analyse points from a mesh and only keep x number (like 4?) of the farthest points from each others. I tried to grab the distances in vex then using delete node but its not working properly, didnt find a way to parse every point and compare between them. Tried average but then again I dont know how to compare each points from each other. Thanks
  8. Hello Guys. I got stuck here in a middle of an project and i can't find a solution. My problem is : I have a grid of points , and an animated point running over the surface of the grid. My "running" point have an attribute that is transferd ( via attrib transfer SOP inside anSolver) to the grid points by an proximity radius. then I use the transfered attribute to isolate only the grid points that are tuched by the "running"point. But the @ptnum of the remaining points is changing. And i need the @ptnum to grow in the order detection ( @ptnum 1, 2, 3, 4, 5 etc) why is that happening to understand better I've attached the scene file ptnum_chaos.hip
  9. Hello! Normally I always find the answers to any Houdini issue that comes into my way, but this time I decided to finally communicate my current issue! My first question ever in odforce hehe So well... I'm doing my graduation film, and is about a shepherd that transforms sheep wool into clouds for doing rain! After some previous phase of research, we decided to give the wool a "cloudy" look, more than giving clouds a "wooly" look. So I'm using volumes to recreate the sheep wool! Thanks to various threads made by countless users here in odforce, I was able to: *Create interesting noise density values for the VDBs, hence giving a "wooly" look to the volume. I wanted "puffy" looking volumes, so I scattered particles in the sheep mesh, and created VDB out of them. *Transfer spatial transformation data from an alembic animated mesh to a volume, this way helping me to maintain the overall noise that will have otherwise been calculated at each frame if I moved the mesh I used for the VDB creation directly. *Deform the noised volume through a volume lattice technique by Juraj Tomori and Matt Estela (I'm enormously grateful for having shared their hip files!!! They saved my life). The volume will keep its noise while being deformed by box, itself deformed by an edit or a bend node. Up until now! Everything is going well! The only issue I have is.... How can I assign the point cache information of an animated lattice in Maya to a box with the same dimensions and subdivisions in Houdini? I thought that maybe an attribute transfer I could transfer the P data.. But I don't know if I need some vex to grab the position of every point in the lattice an assign them to a new matrix... I have no idea.. But knowing how to do this will be excelent! This way any lattice deformations the animators will do in Maya will be directly fetched to the box in Houdini! Any ideas?
  10. In older versions of Houdini I could add a point to a group's selection. Has that changed in H16 because I can't seem to get it to happen? Any advice would be appreciated. Thank you David
  11. Hello! Sory for my English I'm trying create geometry with AttribWrangle node in Detail mode. I use addpoint, addvertex and addprim nodes. When I created some points how could I get access to them into the node? For example, I created point pnt0 = {0,0,0,}. And now I want to create point pnt1 which is close to pnt0: int X = 3; int pnt0 = addpoint(0, set(0,0,0)); int pnt1 = addpoint(0, set()); - and here I want to get position of the first point and add X to each coordinates. Is it possible?
  12. Hello, I'm doing this Mold forest..I'm struggling with the UVs.. I have this tubes like structures , I create two groups , the bottom and top rings ....so I can run a shortestes path node to drw the seam path , the problem is that I must have one of this two groups with only one point per ring to draw only ONE path... This Tubes are part of a model wich I split on threee parts, the floor, this tubes, and the tips.. for the tips the technique works perfectly so you can see what I want to achieve on the hip file ... It's difficult to explained I guess... This image show the top ring group.. Fungus_67.hiplc
  13. I am trying to scatter some points on a circle. But I want the points to be scattered more near the center and less towards the outer side. In the old Houdini Scatter I could do it by making my Circle Primitive type to "Polygon" and then uncheck "Divide Non- Convex Polygon" on the scatter node. However, in the new scatter node of Houdini 14 and 15, this option is not available. Here is what I am trying to achieve, this is with the old scatter node. This is what I am getting with the new scatter node. Please help.
  14. Hi, I create a new project but have a new problem. use to source object its has not problem but when added the point on source objects its changing rotation. I hope, you can help me for ı can fix my files.
  15. Getting point neighbor in Python

    Hello dear community, I am currently trying to setup a city generator as part of my bachelors thesis. For a basic street layout, I am using a voronoi sop on a plane and fuse these points. It would be a big ease to be able to find the neighbors of a point (not vertices) and get their position. I did some workaround by creating a dictionary with position vectors and counting the positions that match, so I can at least count the neighbors. Does anybody know a trick or a function to do this in pythin? I know there is a VEX function that does that, however I don't know VEX pretty much and I am having trouble understanding their usage, although I read the docs. Any kind of help would be much appreciated. Best regards, Nicolas
  16. Hello, I know that there are plenty of examples of vop loops with point clouds, but after searching, haven't found an example/file that helps with this. I can get an attribute growth going with the basic like pc_filter and all of that, but now was trying to make that attib growth happen one point at a time(the closest ones from the points with the attrib initiated) and i can do that for the first point, but after that it doesn't do what i was expecting it to do, stops the growth after finding the first point... Imagine it should be something super simple that i got wrong, but if someone could take a look and let me know what i'm doing wrong i would really appreciate it. Here's a simple file showing where i'm at now Big thanks M odforce_pc_loop_problem.hip
  17. I have primitive groups set up in SOP level, something simple like a box with a voronoi fracture applied with the inside and outside primitive groups. How can I access this primitive group in shop context? I am trying to compare whether or not a shading point belongs to a specified group so I can create a mask. I can create a attribute at sop level to store the group information on the points and that works, but I want to do this in the shop context because the geometry will be heavily subdivided and displaced and I need the accuracy. Any thoughts?
  18. Hey guys, I'm having an issue where the Alpha displays properly in the viewport but doesn't work when rendered. I've done this before, just a simple Constant shader, and it always worked. Here is what it looks like in viewport vs render: I looked at other threads and none of the solutions work in this scene. Here is the scene file: 0007_odforce.hip Thanks!
  19. Hi all, I have a problem with wrong point normals. Basically I have an L-system vine which I am deforming with Wire Deform SOP. I am separating the 'anchor points' of the leaves and I want to add the leaves back after the Wire Deform SOP (if I keep the leaves geometry together, the wire deform screws up the leaf geometry). I also want to do it this way, as I want to control the leaves animation and growth with copy stamping which won't be possible if I keep everything together. But if I separate the anchor points and then add the leaves back with copy SOP, the point normals are different that those I would get if I deform the whole L-system together. I hope it makes sense, any suggestions how to fix it would be greatly appreciated. I attached screenshots and my .hip file with both set ups. Correct normals, screwed up geo: Wrong normals, correct geo normals_lsystem_problem.hipnc
  20. How can i import attribute to geoself() geometry from second input of wrangle node if i don't know type of this attribute. I write function: parameters: native_input = 0 (first input of wrangle node) sample_input = 1 (second input of wrangle node) attribs = string like "attrib1 attrib2 attrib3" native_ptnum = number of point in current geometry where i want create attributes like in second input sampled_ptnum = number of point from second input where i want sample attribute. but cannon import any array attributes like "Cd" and etc... This function correctly worked only if attribute is not array (type = 0 or 1 or 2) :((( void sampleattribs(int native_input; int sample_input; string attribs; int native_ptnum; int sampled_ptnum ) { foreach(string aname; split(strip(attribs), " ")) { aname = strip(aname); if ( haspointattrib(sample_input, aname) ) { int atype = attribtype(sample_input, "point", aname); if (atype==0) { addpointattrib(native_input, aname, int(0)); int value = point(sample_input, aname, sampled_ptnum); setpointattrib(native_input, aname, native_ptnum, value); }; if (atype==1) { addpointattrib(native_input, aname, float(0)); float value = point(sample_input, aname, sampled_ptnum); setpointattrib(native_input, aname, native_ptnum, value); }; if (atype==2) { addpointattrib(native_input, aname, ""); string value = point(sample_input, aname, sampled_ptnum); setpointattrib(native_input, aname, native_ptnum, value); }; if (atype==3) { int def_value[]; addpointattrib(native_input, aname, def_value); int value[] = point(sample_input, aname, sampled_ptnum); setpointattrib(native_input, aname, native_ptnum, value); }; if (atype==4) { int size = pointattribsize(sample_input, aname); string typeinfo = attribtypeinfo(sample_input, "point", aname); float def_value[] = {}; for(int i=0; i<size; i++) append(def_value, 0.); addpointattrib(native_input, aname, def_value); setattribtypeinfo(native_input, "point", aname, typeinfo); float value[]; resize(value, size); int success = -1; //value = point(sample_input, aname, sampled_ptnum); //printf("%d\n", sampled_ptnum); //foreach(float v; value) { printf("%f", v); }; setpointattrib(native_input, aname, native_ptnum, value); }; if (atype==5) { string def_value[]={}; addpointattrib(native_input, aname, def_value); string value[] = point(sample_input, aname, sampled_ptnum); setpointattrib(native_input, aname, native_ptnum, value); }; }; }; };
  21. I was looking into sdf and i found this file from Chris. I slightly modified it to get points colored by a ramp using sdf Does anyone know a better way to do that, in a normalized kind of way? I would like not to have to use the fit range to adjust the color ramp. Later i want to use this method to create custom velocity field on a pyro sim to contain the smoke within the velocity field. Thank you Fred sdf to point color.hip
  22. Hi all, Ok, this is really confusing me. I'm trying to render a pointcloud (as points under the Render>Geo tab of object) with a constant type shader which inherits the alpha & pscale value per point. I'm doing this because I don't really want to light the scene (at all) to save render time - and the points just need to be graphical representations, rather than look like anything 'real'. My issues are: a: Point color always seems to be washed out in the render view compared to viewport. (Because of auto headlight generation I'd assume?) b: The 'constant' shader doesn't allow for a per-point alpha (as far as I can tell), and must be lit to be seen. What I'd like to a achieve: I'd like a shader solution that inherits my user defined pscale & alpha & doesn't need to be lit. Any suggestions? (Massive apologies if this is a rookie thing, as I suspect it probably is. Maybe I'm not searching the correct terms in the help docs/here. I found this post about additive point rendering, but it's not quite what I'm looking for.)
  23. Animated Fractured Geometry

    Hello everyone, I have got a model in a T-pose and a point cache for the animation. I have setup that in houdini using a point VOP but I have no idea how to fracture the character and for the pieces to follow the animation. Here is an example of what I want to do: ------------------------------------------------------------------------------------------------------------------------------------------ I managed to do it with a clothcapture + clothdeform but its really slow, is there any other way to do that?
  24. curve editing [UNSOLVABLE]

    Hi, probably a beginners question, but I'm baffled. How can I enter "manually" the coordinates of a point on a curve? I've search the forums, and read about how entering them in the spreadsheet was wrong (enter the soft lock mode (whatever that is...)) And read very complicated answer involving python script !!! All I need is very basic : I made a curve now I need to modify the coord of 2 points in Y axis those 2 pts are at 2.39245 and I need them at 2.4 quite easy ! Yet I just can't do it (without some simple math + offset) I need to do that a lot, so I'm looking for a solution without calculations or scripting. Am I missing something ??? (again) Can't I enter the coord manually somewhere? (somewhere else than in the coodinates list of the curve node, where they are all in line and inaccessible) thanks!
  25. Hello Everybody, I'm working on a Cloth Simulation in which I'd like to have a set of points to be Pin Constrained. But I'd like to change the Pinned point count over time, so it releases the constraints as the animation goes on. In the documentation on constraints I've found this: How to change the points that are constrained with the pin constraint during simulation By default, the Constrained Points list does not expect the points to change. However, there is a way to work around this and have the list freshly evaluated by DOPs on every frame. Right Click on the Pin Constraint node and select Allow Editing on Contents. Dive into the Pin Constraint node and select anchorobjpointgrouppos1. Change the Point Group parameter to Set Always. See the Anchor: Object Point Group Position help for more information on this node. http://www.sidefx.com/docs/houdini15.0/dyno/constraints So I've tried to do these steps but I couldn't get it to work for some reason. Maybe I'm missing something obvious. I've uploaded a very simple scene file in which I've grouped a set of points and animated the grouping bounding box. If it's no too much trouble would you guys mind taking a look at it and see if anyone can help me out with this issue? Any help or advice is much appreciated. Thanks for you time. Cheers, Laszlo cloth_animated_pinConstraint_v001.hip