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Showing most liked content since 12/23/2017 in all areas

  1. 5 points
    Hello Everyone, Happy New year I've been making a series of videos for beginners over the last couple of months. These require no prior knowledge of houdini. I've uploaded them to youtube as well since Youtube generates really good subtitles automatically. I'm putting the link below for the youtube playlist. I hope you find it useful. Houdini playlist regards
  2. 4 points
    We just released a 4-part particle series I did for LearnSquared: https://www.learnsquared.com/courses/houdini-particles We cover everything from building our own particle solver from scratch, using the built-in Houdini particle POPS, showing how to choreograph and art-direct particle motion, and working through various rendering and instancing strategies.
  3. 4 points
    Hi everyone! I'm an FX artist at Double Negative (London), and currently a Sequence FX Lead for the new Pacific Rim movie. In the past I've also worked at ILM, Blue Sky Studios, Tippett Studio, & Framestore NY. A new session of my destruction course starts in 2 weeks, and there are still some seats left. I've updated the description/video & added some student feedback. Feel free to share with anyone that might be interested. And if you have any questions about it, feel free to send me a message here or on LinkedIn or etc. :-) https://vimeo.com/keithkamholz/cgma-destruction http://www.cgsociety.org/training/course/mastering-destruction-in-houdini
  4. 4 points
    sweet jesus, forget what I said before, this is much more of a nightmare than I thought! I finally got a faster render, but the rabbit hole kept getting deeper, so it took longer & longer to work out With both the principal and classic shaders / GGX, refracting Reflection rays gives a ton of noise, independent of roughness settings. The noise needs high Pixel Samples and increased Refraction Quality settings to fix. Specular from lights is the worst, as implied by light sampling issues mentioned previously - so I turned the light's reflection contribution off and replaced it with reflection cards. Switching the Refraction Model from GGX to Phong helped a lot ( I haven't found a switch in the principled shaders yet so I had to use classic shaders ), there's still a fair amount of noise but now it seems to shade like I expect it; increasing Max Ray Samples was actually effective, and at only 12, which allowed me to reduce the Pixel Samples down to 8. Noise Level worked fine at the default 0.01. Reflection and Refraction Quality needed a boost to 2 and 4 respectively. Limits panel was left as is ; reflect 2, refract 4, Color 4. I was able to cut the render time in half after all this ( changing the shaders to classic to switch off ggx did change the look ), but that's still way too slow for what it is, there should have been no noise in the first place. Stochastic transparency on / off and high samples made 0 difference Sidefx has to fix this! Using a different renderer is certainly a good idea in the meantime I still want to try it with a fresh scene, and in another renderer for comparison
  5. 3 points
    Few tips and tricks to manipulate gas simulation. 1. Independent resolution grid. E.g. Overriding vel grid size independent to a density grid. 2. Creating additional utilities. E.g. gradient, speed, vorticity and etc which can be used to manipulate forces. 3. Forces via VEX and some example snippets. smokesolver_v1.hipnc P.S. Some of this technique are not Open CL friendly though.
  6. 3 points
    Houdini tip | Faster saving of scenes on network drives Simple houdini env var which will speed up saving of large scenes especially notable on network shares.
  7. 3 points
    Here is a breakdown of how I made this bear made out of duplo blocks: The video isn't super comprehensive, I mainly cover setting up the constraints in SOPs, though I briefly touch on some other parts too. But the hip file is available to pick apart! Thanks! duplo_bear.zip
  8. 3 points
    Hello everyone! This is the first demo of a new tool I've been working on in Houdini. The idea is to simplify the process of adding steel reinforcement in concrete fractures, specifically FRC (fiber reinforced concrete) My aim is to produce a single node that takes your simmed geometry and adds these steel fibers along the fractured surfaces. Here are some examples of my tool so far: password = vfx Current controls: - max fiber length - randomize fiber length - max angle (before fiber breaks from the adjacent piece) Things I plan to add: - randomize max angle - fragments of concrete stuck to fibers (as seen in example video below) - fiber straightness (how straight/crooked the fibers are) If you have any cool ideas or suggestions, or feedback on my work so far, let me know! (The idea was inspired by the following breakdown video at 2:39)
  9. 3 points
    I challenged wall generation. maze_sy.hiplc
  10. 3 points
    This is the way I have done it in the past when creating a digital asset from a shelf tool: # Create new digital using OBJ subnet as a base temp_node = hou.node("/obj").createNode("subnet") # Create new digital asset from temp node hda_node = temp_node.createDigitalAsset( name = hda_name, hda_file_name = hdalib_directory + hda_name, description = "DESCRIPTION", min_num_inputs = 0, max_num_inputs = 0, ) hda_node.setName("NAME") # Get HDA definition hda_def = hda_node.type().definition() # -------------------------------------------- # Do whatever you need to do with the HDA here # i.e. Creation, copying and organisation of children: hou.moveNodesTo(tuple(other_premade_node), hda_node) hda_node.layoutChildren() # ------------------------------------------- # Update and save new HDA hda_options = hda_def.options() hda_options.setSaveInitialParmsAndContents(True) hda_def.setOptions(hda_options) hda_def.save(hda_def.libraryFilePath(), hda_node, hda_options)
  11. 3 points
    couldn't get this going, coz they say money don't grow on trees...other stuff do...so i'm dabbling in growing other 'stuff'... (tried crowdsource but i got were zombies...)
  12. 3 points
    Yeah, it's a lot of fun and you can do really cool stuff. Here's a setup I'll go through in my upcoming course, whenever I'll get that out - but yeah, it's in the works.
  13. 2 points
    In this setup I have changed the Gas Enforce Boundary velocity type from Rigid to Volume. I also added a 7% Gas Damp on the target. This seems to help quite a bit. The smoke is mostly staying where it is supposed to. ap_smoke_emit_ring_012118.hipnc With Gas Enforce Boundary working I can disable the Gas Damp to restore a more smokey look.
  14. 2 points
    Hi everybody, Here is my new showreel. A little editing with some shot from Fantastic Beasts and Ghost in the Shell compared to my previous reel. And only one shot i can show from my work at Hybride on Mother!, i can't show right now some stuff from StarWars: The Last Jedi and coming other shows The majority at the FX was make on Houdini. Hope you enjoy !
  15. 2 points
  16. 2 points
    There are so many nice example files on this website that I am often searching for. I wanted to use this page as a link page to other posts that I find useful, hopefully you will too. Displaced UV Mapped Tubes Particles Break Fracture Glue Bonds Render Colorized Smoke With OpenGL Rop Moon DEM Data Creates Model Python Script Make A Belly Bounce Helicopter Dust Effect Conform Design To Surface Benjamin Button Intro Sequence UV Style Mapping UV Box and Multiple Projection Styles Ping Pong Frame Expression Instance vs. Copy (Instance Is Faster) Particle Bug Swarm Over Vertical and Horizontal Geometry Rolling Cube Rounded Plexus Style Effect Pyro Smoke UpRes Smoke Trails From Debris Align Object Along Path Fading Trail From Moving Point Swiss Cheese VDB To Polygons Get Rid Of Mushroom Shape In Pyro Sim A Tornado Ball Of Yarn Particles Erode Surface Unroll Paper Burrow Under Brick Road Non Overlapping Copies Build Wall Brick-By-Brick FLIP Fluid Thin Sheets Smoke Colored Like Image Volumetric Spotlight Moving Geometry Using VEX Matt's Galaxy Diego's Vortex Cloud Loopable Flag In Wind Eetu's Lab <--Must See! Wolverine's Claws (Fracture By Impact) Houdini To Clarisse OBJ Exporter Skrinkwrap One Mesh Over Another Differential Growth Over Surface Rolling Clouds Ramen Noodles Basic Fracture Extrude Match Primitive Number To Point Number Grains Activate In Chunks Fracture Wooden Planks Merge Two Geometry Via Modulus Fill Font With Fluid DNA Over Model Surface VDB Morph From One Shape To Another Bend Font Along Curve Ripple Obstacle Across 3D Surface Arnold Style Light Blocker Sphere Dripping Water (cool) Exploded View Via Name Attribute VEX Get Obj Matrix Parts eetu's inflate cloth Ice Grows Over Fire Flying Bird As Particles DEM Image To Modeled Terrain Pyro Temperature Ignition Extrude Like Blender's Bevel Profile Particles Flock To And Around Obstacles BVH Carnegie Mellon Mocap Tweaker (python script) Rolling FLIP Cube Crowd Agents Follow Paths Keep Particles On Deforming Surface Particle Beam Effect Bendy Mograph Text Font Flay Technique Curly Abstract Geometry Melt Based Upon Temperature Large Ship FLIP Wake (geo driven velocity pumps) Create Holes In Geo At Point Locations Cloth Blown Apart By Wind Cloth Based Paper Confetti Denim Stitching For Fonts Model A Raspberry Crumple Piece Of Paper Instanced Forest Floor Scene FLIP pushes FEM Object Animated Crack Colorize Maya nParticles inside an Alembic Path Grows Inside Shape Steam Train Smoke From Chimney Using Buoyancy Field On RBDs In FLIP Fluid Fracture Along A Path COP Based Comet Trail eetu's Raidal FLIP Pump Drip Down Sides A Simple Tornado Point Cloud Dual Colored Smoke Grenades Particles Generate Pyro Fuel Stick RBDs To Transforming Object Convert Noise To Lines Cloth Weighs Down Wire (with snap back) Create Up Vector For Twisting Curve (i.e. loop-d-loop) VDB Gowth Effect Space Colonization Zombie L-System Vine Growth Over Trunk FLIP Fluid Erosion Of GEO Surface Vein Growth And Space Colonization Force Only Affects Particle Inside Masked Area Water Ball External Velocity Field Changes POP particle direction Bullet-Help Small Pieces Come To A Stop Lightning Around Object Effect Lightning Lies Upon Surface Of Object Fracture Reveals Object Inside Nike Triangle Shoe Effect Smoke Upres Example Julien's 2011 Volcano Rolling Pyroclastic FLIP Fluid Shape Morph (with overshoot) Object Moves Through Snow Or Mud Scene As Python Code Ramp Scale Over Time Tiggered By Effector Lattice Deforms Volume Continuous Geometric Trail Gas Enforce Boundary Mantra 2D And 3D Velocity Pass Monte Carlo Scatter Fill A Shape Crowd Seek Goal Then Stop A Bunch Of Worms Potential Field Lines Around Postive and Negative Charges Earthquake Wall Fracture Instance Animated Geometry (multiple techniques) Flip Fluid Attracted To Geometry Shape Wrap Geo Like Wrap3 Polywire or Curve Taper Number Of Points From Second Input (VEX) Bullet Custom Deformable Metal Constraint Torn Paper Edge Deflate Cube Rotate, Orient and Alignment Examples 3D Lines From 2D Image (designy) Make Curves In VEX Avalanche Smoke Effect Instant Meshes (Auto-Retopo) Duplicate Objects With VEX Polywire Lightning VEX Rotate Instances Along Curved Geometry Dual Wind RBD Leaf Blowing Automatic UV Cubic Projection (works on most shapes) RBD Scatter Over Deforming Person Mesh FLIP Through Outer Barrier To Inner Collider (collision weights) [REDSHIFT] Ground Cover Instancing Setup [REDSHIFT] Volumetric Image Based Spotlight [REDSHIFT] VEX/VOP Noise Attribute Planet [REDSHIFT] Blood Cell Blood Vessel Blood Stream [REDSHIFT] Light Volume By Material Emission Only [REDSHIFT] Python Script Images As Planes (works for Mantra Too!) Dragon Smashes Complex Fractured House (wood, bricks, plaster) Controlling Animated Instances Road Through Height Field Based Terrain Tire Tread Creator For Wheels Make A Cloth Card/Sheet Follow A NULL Eye Veins Material Matt Explains Orientation Along A Curve Mesh Based Maelstrom Vortex Spiral Emit Multiple FEM Objects Over Time Pushing FEM With Pyro Spiral Motion For Wrangle Emit Dynamic Strands Pop Grains Slope, Peak and Flat Groups For Terrains Install Carnegie Mellon University BVH Mocap Into MocapBiped1 Ramp Based Taper Line Fast Velocity Smoke Emitter Flip Fill Cup Ice Cubes Float [PYTHON]Export Houdini Particles To Blender .bphys Cache Format Collision Deform Without Solver or Simulation Mograph Lines Around Geometry Waffle Cornetto Ice Cream Cone Unroll Road Or Carpet Burning Fuse Ignites Fuel or Painted Fuel Ignition Painted Fuel Combustion Small Dent Impact Deformation Particle Impact Erosion or Denting Of A Surface Helicopter Landing Smoke And Particles Radial Fracture Pieces Explode Outwards Along Normal Tangent Based Rocket Launch Rolling Smoke Field Tear/Rip FLIP (H12 still works in H16) Rain Flows Over Surface Smoke Solver Tips & Tricks Folding Smoke Sim VEX Generated Curve For Curling Hair Copy and Align One Shape Or Object To The Primitives Of Another Object (cool setup) A Better Pop Follow Curve Setup FEM Sea Cucumber Moves Through Barrier Fracture Cloth Smoke Confinement Setup Merge multiple .OBJ directly Into A Python Node Use Google To Discover Attached HIP Files Useful Websites: Tokeru Houdini Houdini Vex Houdini Python FX Thinking iHoudini Qiita Ryoji Video Tutorials: Peter Quint Rohan Dalvi Ben Watts Design Yancy Lindquist Contained Liquids Moving Fem Thing Dent By Rigid Bodies Animating Font Profiles Guillaume Fradin's Mocap Crowd Series(no longer available) Swirly Trails Over Surface http://forums.odforce.net/topic/24861-atoms-video-tutorials/ http://forums.odforce.net/topic/17105-short-and-sweet-op-centric-lessons/page-5#entry127846 Entagma SideFX Go Procedural
  17. 2 points
    Ok, I think I have found the solution. Before you submit your geometry to the fluid simulation you must promote all attributes you want to melt, to points. So Cd, uv and shop_materialpath should reside on points before the simulation begins. After simulation, in the meshing network, you need to add those attributes (Cd, uv, shop_materialpath) to the transfer list of the fluidcompress and the particlefluidsurface nodes. After the particle surface node you need to promote the attributes back to their appropriate resting area. So uvs get promoted back to vertex and shop_materialpath gets promoted back to primitives.
  18. 2 points
    I'm glad to introduce my new asset for Houdini 16.0 / 16.5.
  19. 2 points
    I haven't abandoned this btw, just haven't had a lot of time to work on it.
  20. 2 points
    I'm sure this has been said many times on this thread for 15 , 15.5, 16, 16.5 and now 17 But The Cloth/FEM Solver needs to be UPDATED please, thank you! Is awfully slow.
  21. 2 points
    if you know that your overall settings in the dopnet for the fire sim will stay the same and all you want to replace is essentially the incoming sources then I would do the following: - setup a source for each of your windows. - pipe that into a switch node with value $WEDGE - amount of wedges = amount of sources. - enjoy time off while computer cranks through all your sims with one button push this of course applies to all your fields you want to source into your sim
  22. 2 points
    Found lazy hack using two Add nodes. lazy_phyllotaxis.hipnc
  23. 2 points
    I wanted to share my new reel - mainly Houdini but there's are also a couple of older Maya clips on there too. Any feedback very welcome...
  24. 2 points
    Howdy my dudes, I've been taking at a stab at building out a "portal" type shader for a few days now, and I'm pretty stuck. To elaborate, the goal is to basically to render from a second camera onto a texture (or render buffer), and then project it onto a piece of geometry to be rendered like any other object. Thus creating the illusion of looking into one portal, and out of a second portal (just like the game Portal). I've already solved rendering from the perspective of the other camera (I think.... I basically rebuilt fromNDC() in /mat/), however I'm currently stuck on how to project it properly back onto the geometry. Let's define the current render camera as "CameraA" and the second, portal camera as "CameraB" for ease of explanation. The issue that I'm running into is that the method I'm using requires me to sample the rendered scene from CameraB, as a texture. The reasoning being, that we need to clip the texture to make sure we're not looking at a squashed scene, but rather a scene that's clipped by the bounds of the portal geometry. However as far as I'm aware, there's nothing like Unity's render targets in Houdini. You could argue that, that's the purpose of the Render COP, however it's far slower than just shooting more rays into the scene from CameraB. Mestela sent me this lovely video by Roman Saldygashev in which he achieved the effect in mantra, so i know it's possible. For even more context, I've been following along with this post by Tom Hulton and his implementation in Unity, http://tomhulton.blogspot.com/2015/08/portal-rendering-with-offscreen-render.html Though in the attached file, I don't include the camera matching transformations he describes, let's just focus on the portal rendering.... I'm going to attach my test file to this post so all the smart people here can rip it to shreds. Please let me know if you think I'm totally approaching this problem incorrectly as well, as shader math is certainly not my strongest skill... If anyone has a link to the "Stupid RenderMan Tricks" pdf that inspired both Roman's effect and Tom's effect, that'd be incredible, because all searches on my end have turned up empty, so i'm kinda just winging it right now. JR_PORTALS_v004.hipnc
  25. 2 points
    Howdy partners, So one of the g00ns (Flight404) in our lil chat group had a question on dynamically cutting a triangle by its edge duals (basically create a triangle with the midpoints of each edge, and then 3 other new triangles that each connect back to one of the input triangles points) which i thought was a fun problem. Luckily i have tons of experience in this area as I've been dealing with similar problems for that KD-Tree teaser thing I mentioned briefly at the end of my last post (go watch it). Unfortunately i can't think of a parallel method for solving the problem that doesn't create overlapping points on edges (since 2 prims can contain the same edge, solving on prims will double up points on shared edges), but I did get it running pretty fast. It's a QT 3.14 effect, and I've done my best to comment the code. It's all relatively simple, so hopefully you learn some stuff clicking through it! Gosh I really need to update my website with this stuff... JR_TriDiv.hip
  26. 2 points
    import hdefereval hdefereval.executeDeferred(hou.undos.performUndo)
  27. 2 points
    In case it's useful to anyone, here's an asset I made a little while ago and finally got round to documenting. It takes one or m ore curves and generates 3 levels of braided curves - first level coiled around the input, second coiled around the first and the third around the second. Additionally it can make a final level of 'hairs'. It supports animated inputs, and will transfer velocity onto the output but in many cases it's probably better to use a timeshift to generate the rope on 1 frame and use a point deform or similar. This also avoids texture jumping problems if using the supplied 'pattern' colour method. There's a fairly comprehensive help card with it and below is a demo video. If anyone finds bugs or problems, please let me know and I'll try and fix them when I have time... I'd be very interested to see anything anyone makes with it... TB__RopeMaker_1_0.hda
  28. 2 points
    go back up to your box1, drag the label Size into the middle field of next row (ie. the middle 0), pick Relative Channel Reference You'll see it puts ch("sizex") into the field, change the x to y because we want to move the box up depending on its y size. Now you'll see it's moved up too much, we want to move just half the height, so change the expression to ch("sizey")/2 Now you'll see the bottom of the box is at 'ground' level....no matter how 'high' the box is... Then your scale will work properly.
  29. 2 points
    Two buttons on each help page: Typo and Inaccurate, similar to the ❤️ button. You click the button and can highlight the text that is a typo or incorrect. Click the button again and the page submits it to the Docs team, effectively making all of us proofreaders. You could go all out and have a little comment box pop up too. Being too lazy to file a bug report unless things are crashing, I never do for typos or inaccuracies in the docs, which aren’t often in Houdini’s docs, but sometimes things change over versions and a line or two of a doc is made inaccurate, but would if it were just a click or two.
  30. 2 points
    When you add some transform attributes, it stops guessing them. Therefore no rotation, if the attribute values didn't describe any rotation. Sine wrangle does affect boxes, but the grid resolution is too low, and automatic orientations will be quite straightened, point normals can give you a hint on this. Corner cubes still rotated though. Actually, for those who interested, there is pseudo-code section in the linked help page (again) with some info on how it works internally, guessing defaults and using inputs: Key: X = pivot matrix (translate by -pivot) O = orient matrix S = scale matrix (scale * pscale) L = alignment matrix (*) R = rot matrix T = trans matrix (trans + P) M = transform matrix (*) The alignment matrix (L) is defined by N or v and up. IF N exists AND up exists and isn't {0,0,0}: L = mlookatup(N,0,up) ELSE IF N exists: L = dihedral({0,0,1},N) ELSE IF v exists AND up exists and isn't {0,0,0}: L = mlookatup(v,0,up) ELSE IF v exists: L = dihedral({0,0,1},v) IF transform exists: Transform = X*M*T ELSE IF orient exists: Transform = X*S*(O*R)*T ELSE: Transform = X*S*L*R*T
  31. 2 points
    I think they're good. This thread is from 2014...
  32. 2 points
    Houdini engine for Maya should be able to do this no?
  33. 2 points
    More inspiration: https://necessarydisorder.wordpress.com/2017/11/15/drawing-from-noise-and-then-making-animated-loopy-gifs-from-there/
  34. 2 points
    Hi! Everyone, i made a little RnD the lasts week on the Rope Simulation. Enjoy
  35. 2 points
    Hey guys, I very new to Houdini and was messing around with the differential line growth tutorial from Entagma. Instead of using a single circle I used a copy and transform node to have that growth relative between multiple clones, then after the solver I want to translate each primitive on the z axis. I have been able to achieve it manually but it's just the opposite of what houdini is cool for, so I tried the for each loop trying to translate each primitive by increment but it didn't work. I'm sure it's very easy that I am missing because of my lack of knowledge but should be for sure piece of cake for most of you. Cheers!
  36. 2 points
    Still playing with this setup, been loads of fun. A couple of recent renders.
  37. 2 points
    I wrote a guide on writing simple node operating on OpenVDB volumes in HDK: Creating simple C++ OpenVDB node in HDK What it does is basically: the node will take a VDB volume as an input and point cloud, then at position of each point it will activate matching voxel in VDB volume. You can also check repository with the code: VDB Activate from Points
  38. 2 points
    Yeah, sometimes I like to watch paint dry too. (especially when I'm paid by the hour) Here is an example scene that demonstrates lighting with only material emission. There are no lights in this scene. The shader uses a RaySwitch to decouple material based emission from incandescent emission. This allows you to overdrive incandescent output while not blowing out your diffuse. You can even choose an alternate color for the incandescent light as shown in this scene. The sphere emits RED but the incandescent emits BLUE. ap_rs_light_by_material.hiplc
  39. 2 points
    Hey everyone! Here's a demo of some point cloud tools I created to calculate concave and convex curvature as well as gradient and curl direction, also sharpening. Forgot to mention in the demo that the curvature calculation is a great way to do differential growth by advection along normal * curve * noise * parm. Also, the curl calculation can be used to make grass patches and groom fur by orienting curves along the direction to add swirly variance. There's a lot of ways these tools can be handy, interested to see what you all come up with! Let me know if you have any questions, enjoy! curveGradientCurlSharpen_v002.hipnc
  40. 2 points
    Gifstorm! First I've used a visualizer sop to show @v coming out of the trail sop: That makes sense so far. To make the next step easier to understand, I've shrunk the face that sits along +Z, and coloured the +Y face green, +X red, +Z blue. So, that done, here's that cube copied onto the points, with the v arrows overlaid too: The copied shapes are following the velocity arrows, but they're a bit poppy and unstable. So why are they following, and why are they unstable? The copy sop looks for various attributes to control the copied shapes, @v is one of them. If found, it will align the +Z of the shape down the @v vector. Unfortunately what it does if it has only @v is a little undefined; the shapes can spin on the @v axis when they get near certain critical angles, which is what causes the popping and spinning. To help the copy sop know where it should aim the +Y axis, you can add another attribute, @up. I've added a point wrangle before the trail, with the code @up = {0,1,0}; ie, along the worldspace Y axis: you can see all the green faces now try and stay facing up as much as they can (note the view axis in the lower left corner), but there's still some popping when the velocity scales to 0, then heads in the other direction. Not much you can do about that really, apart from try some other values for @up, see if they hide the problem a little better. What if we set @up to always point away from the origin? Because the circle is modelled at the origin, we can be lazy and set @up from @P (ie, draw a line from {0,0,0} to @P for each point, that's a vector that points away from the origin): Yep, all the green faces point away from the center, but there's still popping when @v scales down to 0 when the points change direction. Oh well. Maybe we can venture into silly territory? How about we measure the speed of v, and use it to blend to the @up direction when @v gets close to 0? Better! Still a bit poppy, but an improvement. Here's the scene with that last setup: vel_align_example.hipnc To answer the other key words in your topic title, I mentioned earlier that the copy sop looks for attributes, obviously @v and @up as we've used here, but if it finds others, they'll take priority. Eg, @N overrides @v. @N is still just a single vector like @v, so it too doesn't totally describe how to orient the shapes. You could bypass the trail and the wrangle so that there's no @v or @up, set @N to {0,1,0}, and all the shapes will point their blue face towards the top. Without any other guidance, it will point the red side of the shapes down +X. If you give it @N and @up, then it knows where point the green side, and you get a well defined orientation. While using 2 attributes to define rotation is perfectly valid, there are other options. The one that trumps all others is @orient. It's a single attribute, which is nice, and its party trick is that it defines orientation without ambiguity, using a 4 value vector. The downside is quaternions aren't easy to understand, but you don't really need to understand the maths behind it per-se, just understand what it represents. The simplest way is to think of it as @N and @up, but glommed into a single attribute. Another way is to think of it as a 3x3 matrix (which can be used to store rotation and scale), but isolated to just the rotation bits, so it only needs 4 values rather than 9 values. In houdini, you rarely, if ever, pluck quaternion values out of thin air. You normally generate what you need via other means, then at the last minute convert to quaternion. Lots of different ways to do this, coming up with ever funkier smug ways to generate them in 1 or 2 lines of vex is something I'm still learning from funkier smug-ier co-workers. Eg, we could take our fiddled @v, and convert it to a quaternion: @orient = dihedral({0,0,1} ,@v); What that's doing is taking the +Z axis of our shape-to-be-copied, and working out the quaternion to make it align to @v. You could then insert an attrib delete before the copy, remove @N, @v, @up, and now just with the single @orient, all the shapes rotate as you'd expect. vel_align_example_orient.hipnc
  41. 1 point
    Look at this from Steven to understand the voroni fracture. Also you can just affect the outer mesh, make sure to uncheck "Create inside Surface". You can control where you put more density with a paint node, attributes, groups, etc
  42. 1 point
    Thank you so much, Jesper!! I am used to C4D but really like the power of Houdini. Sometimes I get a bit lost on what is going on behind the hood though. That fixed it. (I will added a node to move the points used for the Copy node slightly in the normal direction to make it look a bit better). Here is result: Belt.hiplc
  43. 1 point
    Hello Everyone, We are very excited to present to you this promo video featuring the content of all our Houdini workshops. Introduction To Houdini For 3D Artists https://rebelway.net/intro_to_houdini_for_3d/ Introduction To Houdini For FX Artists https://rebelway.net/intro_to_houdini_for_fx/ Advanced Asset Creation Using Houdini For VFX & Games https://rebelway.net/advanced-asset-creation-in-houdini-for-vfx-and-games/ Mastering Pyro FX In Houdini https://rebelway.net/mastering-pyro-fx-in-houdini/ Please visit the course pages for more details and If you have any questions feel free to email us at rebelwayinfo@gmail.com or PM us directly. Thanks Rebelway Team.
  44. 1 point
    Rather than trying to alter the seed for each shatter in a loop, how about you copy your objects to shatter to your template points first, then in a for/each loop shatter each copy individually? Since the volume noise you're using is based on global P, each copy will evaluate differently. Check this example file. rbdTest_toadstorm.hipnc
  45. 1 point
    think this will work ... $F > 1 && $F<10 || $F>15 && $F<20
  46. 1 point
    So here's attempt First of all, this is not an universal skin shader, exact replica or anything like that, I just tried to put some typical 'contemporary' methods into network. It is a mix of PBR Diffuse, PBR Single Scatter ( introduced in 16.5), and two PBR Reflections. It should showing what is possible to do, feel free to experiment with nodes inside shader network. There's just one subsurface scattering shader in mix. Houdini PBR Single Scatter has all map-able attributes, like scattering distance or attenuation color (while in old Mental Ray's Fast Skin, blurring radius is not) - things like exaggerated back scatter around ears or variances in attenuation color, are performed by simple trick: point color is used as mask for modulation. One SSS shader should be much faster to render than three, obviously. So at the end of the day, only typical Mental Ray's Fast Skin feature is screen blending of layers. I added switches between screen blend and plain additive. Important parameters: - Diffuse and SSS tint: that's 'modern' method, to multiply diffuse and SSS texture by complementary color, diffuse in light blue, SSS in orange. Overall is nearly the same as original color of texture, while complementary colors are there to get stronger diffuse - SSS difference. - Diffuse and SSS power: actually a gamma value, 1 is original, more than 1 is exaggerated darker color. - Diffuse and SSS Weights: for more of 'old paintings' style, feel free to raise the SSS weight. - Screen blending, Diffuse vs SSS, Reflections vs Diffuse and SSS: feel free to disable them just to see what happens. Nice side effect of screen blend is clumping of maximum direct lighting ( inside shader I set this to 1.25), making it easier to sample by Mantra. - Two reflections, first is wide, it acts more like additional diffuse shading. Second is sharp, intentionally disabled at edges. Bu some convention, shading model is set to Phong, as Phong does not fade the wide reflections (contrary to GGX) - so somehow Phong fits better, here. Any reflection parameter is a subject for tweaking, except maybe just one: in case of skin, it's always blueish tone, AFAIK that's natural effect of exaggerating the complementary reflection color in case of scattering media, something not automatically set by layered shading used in renderers like Mantra. Regarding wikihuman files, I've reduced resolution of bitmaps to make a smaller download, also I've used only three maps: diffuse color, specular color, and main displacement. Get files (around 30 Mb) there.
  47. 1 point
    so, I made it, almost what I need, if somebody interested in or want to try, welcome! and any comments and changes welcome too) Fly Camera https://drive.google.com/open?id=1NsoI_5LCUGwXKkNW8Zf6_OWkIJcldrZH its asset camera, help and instruction inside right on asset
  48. 1 point
    ok, here's my hillbilly approach, can't compare with the mestela wrangle of course, oh well... Now the diva can have as many humps as she'd like...(just make sure the circle divs is even..but it's not a show stopper), takes 2 secs to dial in instead of starting from scratch like in Max...(that's not Max bashing either...I do shitloads of MCG in Max so I'm confident I could procedurally do this in Max too) (little bonus that you can use the twist in polyextrude too !!!) (added droop if you need it...for the rim) vu_icecream_top.hipnc
  49. 1 point
    I believe that this is not normal pass as you would call it, but several lights with different colors. For example if you have 3 main lights in the scene you just set them as RED, GREEN and BLUE, and that's how you can control lights in post.
  50. 1 point
    You probably need to add the maya shaders to your shader path. We had to do the reverse when rendering houdini ass files through maya.