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Showing most liked content on 03/13/2019 in all areas

  1. 1 point
    There is a VEX function to find the closest point > https://www.sidefx.com/docs/houdini/vex/functions/nearpoint.html And for a list of the all the closest points in a geometry https://www.sidefx.com/docs/houdini/vex/functions/nearpoints.html
  2. 1 point
    It took me quite a while to understand what is happening there looks like very overcomplicated code for a simple task. vector pos is returning 0 as in code: vector pos=point(1,"P",origin); You are asking for P (position) from input 1 (your sphere) of the point number "origin" which in your case is "115" in hip you sent. Your sphere has only 1 point (number 0). There is no point number "115" therefore it fails and returns {0,0,0}. ps. You don't need to export output to terminal to debug this (using printf), you can just export global variable and have live output of your work in "geometry spreadsheet" @test = pos; SideFX help file is very extensive and worth reading! Better than getting wrong ideas from youtube and potentially inexperienced people
  3. 1 point
    try the "centroid" expression instead: centroid("../mynode",D_X),centroid("../mynode",D_Y),centroid("../mynode",D_Z)
  4. 1 point
    I finally uploaded an excerpt of the Reaction-Diffusion kernel from "Ready" I ported to Houdini OpenCL a while ago: 750,000 points and it runs almost in realtime on a GTX 1080 TI. This is an OpenGL render that shows exactly how it looks in the viewport - the mesh is so dense that it vanishes... :-) Cheers, Tom
  5. 1 point
    Oh man! You did art with those vectors. I'm jealous!
  6. 1 point
    Thank you! And yes, by 'multiplying vectors' I was thinking of extending or shortening them, not thinking of using cross products here. So this is a visual summary in 5 steps: When we want to project the grey points from the inner circle on the plane of the outer points and their normals (turqoise), we aim in the opposite direction facing away from the plane points by subtracting circle point positions from the plane positions (yellow), create rectangular vectors to the plane normals by calculating a cross product of the aim direction and the plane points normals (red), and build the cross product of the planes normals and the rectangular directions while adding the planes position (green). When applying this result to the circle points positions, all points are projected on their targeted planes. int pt_plane = nearpoint(1, v@P); vector pos_plane = point(1, 'P', pt_plane); vector nml_plane = point(1, 'N', pt_plane); v@dir = v@P - pos_plane; // yellow v@rect = cross(v@dir, nml_plane); // red v@proj = cross(nml_plane, v@rect) + pos_plane; // green v@P = v@proj; project_on_plane.hiplc
  7. 1 point
    - VEX Wranggle autocomplete and dynamic help display, like python shell. Please, its time..
  8. 1 point
    Hello all. I wanted to share my production library of tools I have posted on Github. Previously a lot of these were posted on Orbolt.com after my 2016 GDC talks. The tools were originally designed to be used in a HOUDINI_PATH style library as opposed to individual hdas. In this manner they can include a larger array of script based tools that don't fall in the paradigm of Orbolt. This toolset is generally complementary to the GameDev, Mops, etc toolset, there are only a few overlaps nowadays. There are two primary libraries of tools. https://github.com/LaidlawFX/LaidlawFX - This is the production library built up over the last decade of work that has been cleansed of studio specific work. This currently contains a set HDA's, a common python library, shelf tools, and example files on how to used the .hdas. Some fun tools in here are an Ivy Generator inspired by Thomas Luft Ivy generator http://graphics.uni-konstanz.de/~luft/ivy_generator/ . File Cache nodes that have been tested on over a dozen productions. RBD to FBX extractors, and an array of ROP tools. Also a module of python code that includes a few sub-modules such as verbosity logging, multiple hda queuing, fbx exporting, file explorer opening, and the large set of options for file caching. Additionally it contains shelf scripts so that you no longer need to use the Material Library, you can just tab and use the shaders like normal nodes. https://github.com/LaidlawFX/HoudiniEngineDev - This is over one hundred hda's to test Houdini Engine implementations in different DCC's and game engine. Each of them test a simple principle from UI parameters to different geometry types and more. Hope they help you at some point. Feel free to branch or leave comments here and I can update the source. Thanks, -Ben
  9. 1 point
    there is a master class... it pretty much solve your question.
  10. 1 point
    It's nice to stick with nVidia in case you decide to jump into GPU rendering.
  11. 1 point
    what if the self buttons were creating DOP setups inside one SOP network instead of having a Geometry node, a DOP network for simulation and another Geometry node to import the data and save to disk. It makes much more sense to see the data flow from top to bottom in one network without having to jump to different levels for no reason. maybe it's just me... grains.hipnc
  12. 1 point
    The animation is good, but why does alot of songs today seem like Ariana Grande is singing them all; with Nicki Manaj the harder side kick ?
  13. 1 point
    You're losing sight of the bigger picture here, which is to create art. FX TD's are by definition going to be on the technical side of things, but their goal is to facilitate the creation of art. The final image is what matters, 99% of the time. People with engineering mindsets sometimes like to get caught up in the "elegance" or "physical correctness" of their solutions, but that stuff rarely (if ever) matters in this field. Rotating an object is conceptually a simple thing, but it turns out that there's quite a bit of math involved. Is it really insulting one's intelligence to not assume that every artist is willing to study linear algebra to rotate a cube on its local axis? I do know how to do this, and I still don't want to have to write that code out every single time. It's a pain in the ass! Creating a transform matrix, converting to a quaternion, slerping between the two quaternions, remembering the order of multiplication... remembering and executing these steps every time gets in the way of exploration and play. Besides, all of that is only possible because SESI wrote a library of functions to handle this. Should we be expected to also write our own C++ libraries to interpolate quaternions? Should we be using Houdini at all, instead of writing our own visual effects software? Who engineered the processor that you're using to compute all this? This is a rabbit hole you'll never escape from. Anyways, Entagma and MOPs are not officially affiliated at all, so Entagma's core mission of reading white papers so that you don't have to is unlikely to change.
  14. 1 point
    Hello, here is some of my attempts to do something similar. But I can't get a similar level of detalization in mantra. If somebody can suggest some tips it wound be amazing volume is still a little bit blurry, I guess it could be because of texture resolution vol-0001_volume_v01.hip
  15. 1 point
    Ok, ill bite here. Ive been wanting to understand these effects for awhile, so maybe this will spark some experimentation. Heres my initial idea for making it work. I'll spend a bit more time documenting the process tommorow, but heres the basic steps. Its all done in a solver node: 1 - resample a line, adding a point each frame (alterable with an attribute) 2 - avoid_force - use a point cloud to sample all the nearby points and create a vector that pushes them away from each other 3 - edge_force - measure each line segment and create a force which attempts to extend the line to a maximum distance. (this was difficult as if you have a totally straight line you never get any interesting motion. My crap solution was to turn the direction vectors into quaternions and slerp between them) 4 - add up the edge force and the avoid force and move the points a little bit along that vector. 5 - use a ray sop to make the points stick to a surface. As long as the movement is not too great, this isn't too bad. I've ran out of time to tweak this tonight, hopefully i'll get back to it soon. This version barely works! Id love to see other peoples ideas for how to create this. sopsolver_growth.hip