Leaderboard

Hello everyone! For the past 8 weeks I have been working on a Japanese Town House generator! This project was made for Breda University of Applied Sciences as a part of my Block A. This is my first Houdini project, so if anyone has feedback for me it would be greatly appreciated. The project was made from scratch as I did not find the built-in Labs building generator easy to build upon. The building generator allows you to change both the roof tiles, the lattices, the windows and the flags for different variances. The size of the building is determined by user placed bounding box, so the tool is able to generate an entire street from just a blockout! Here you can see a diagram of the basic logic used to generate the buildings, excluding the preview mesh generation. I have also made a short video using PDG to showcase different ways that the building generator can create distinct and unique outputs: WhiteOutSpedUp (1) (1).mp4 Here is the tool working in Houdini SpedUpHoudiniShowcase.mp4 And finally, the tool working in Unreal! ToolInUnreal.mp4 Thank you everyone for reading, if you have any questions please ask away!

nah. none of these really add much to usability flat single-color icon palettes are not really in vogue anymore and make it harder to discern between tools the text labels are unreadable when embedded into nodes, especially when names are long roll-out property drawers aren't adding anything new that you can't already get by pressing P or whatever of all the things you choose to add to the limited real estate of the timebar, you want to include an FPS control? how often does one change the FPS of a shot during production? what is the value add? it kinda just seems like you're used to a GUI that's more like blender and you want houdini to follow suit? but little of this is adding any usability, it's just a reskin.

Hello fellow magicians I've released my latest project Skull Beach and raised some interest regarding the method I used for the foam. I want to share a hip file with the basic principle behind this fx. Have fun with it, improve on it, and don't hesitate to share your creations! vellum_foam.hip

I usually do it like this. gradient.hiplc

I have reworked Alejandro's fill a flip collider from an exterior source. This re-work of the network uses the newer H20 nodes. NOTE: If you get a font error, just pick one that is on your system. Original HIP files found here: ap_pazuzu_FLIP_fill_FONT_from_outside_050824.hiplc

Its been a while since I posted progress in this topic. Here is the latest project that I been working on my spare time, always trying to improve my small scale pipeline. I hope you like it! Cheers!!

given two points on the long edge of the rectangle, let's say they're point 0 and 1: vector p0 = point(0, "P", 0); vector p1 = point(0, "P", 1); vector n = normalize(p0 - p1); // compute matrix that rotates the normalized edge onto +X matrix3 d = dihedral(n, {1,0,0}); // transform points with this rotation @P *= d;

I am excited to present the latest version of my modeling addon for Houdini. The core and tools have been practically rewritten from scratch, with the main focus on moving away from a separate, foreign UI and fully utilizing Houdini’s native features for tool interaction. Modeler now operates based on Houdini's radial menus, hotkeys, and shelf tools. Release video

@Ian10210123 We’re close to a solution! Plus, the first file (2D rotation) gives the same result as the simulation. I think we can now achieve this pretty easily using COP 2 in Houdini 20.5. Definitely worth a try! Just sharing some tests! I'm using something like UV coordinates in tangent space and mapping it like a texture—basically a spherical map with tiling. In DOPs, I managed to get some nice fluid-like movement going. There's always room to improve, and I just need more time to refine it, but it's getting close to the concept I'm aiming for! He also mentioned time-dependent movement in COPs, and I think this would be pretty doable in the new COPs. Just need to dial in a better smoke/fluid simulation to get the look right. Plus i forget to make gray scale and relief those or displacement but its manageable.

Copernicus and system BY Jose_L_Molfino with Touch with CHOPS. endless fun and so much possibility for Patterns now ..Heaven

Hi magicians, I just updated my portfolio and wanted to share some making of videos of projects: www.caskaldesign.com Making ofs: More stuff on my vimeo: https://vimeo.com/user1525441 Cheers!

without reseeding you can just delete points having a higher pointnumber than a certain value if (@ptnum > 1000){ removepoint(0, @ptnum); } i've attached a sample file with some different approaches and some sticky notes as well, i hope that is helpful you can get the velocity field out of a flip sim with an import dop fields, for one solution i fed it into a solver and for another one a setup a popsim with pop advect by volumes. both approaches use reseeding. i also tested a quick setup with reseeding turned off. hope this helps! flipvel.hipnc

check this VEX. inertiatensor.hipnc

Or without a double intersect call: vector A = point(0, "P", 66); vector B = normalize(A-v@P); vector C = v@P + B * .1;// 0.1 to avoid overshooting int prim; vector primuv; xyzdist(0, C, prim, primuv); vector surfaceP; prim_attribute(0, surfaceP, "P", prim, primuv); v@field1 = normalize(surfaceP-v@P);

I followed Mikael Pettersen's vellum water balloon tutorial. ap_mp_vellum_water_balloon_041023.hiplc

untitled.mp4 pointrelax_simple.hip

Any effect resolution depends on how close it is to the camera. Do your shot planning first, then add resolution as needed.

I developed this tool to make a faster and easy-to-read version of the combination of Pre-Flight Scene tool and labs archive project tool. Let's take a look of the advantage of my tool: about file viewer 1. faster loading speed than Pre-Flight Scene 2. allow to filter by node name, file name and extension 3. show absolute and relative path. 4. tell you which path is not under $HIP 5. double-click the node name and jump to the node 6. show the number of link status and the number of files with $HIP path about package 1. allow to copy Non-$HIP files to the folder where your .hip file is and replace the path to $HIP. 2. toggle of copy sequence files. Installation Create a new tool in shelf and copy the python codes. Don't be shy to give me any suggestion and feedback FileCollector.txt

Hi, you are reading point number form second input to goalpt variable but point numbers of this goal geo changing each frame. Calculating id attribute on this geo so that id value would be constant and finding point number through id in DOP will solve this problem. ParticleTarget_01.hipnc

There're many ways to control motion, fade over time, power, curvature, distance from a boat and so on. Ripple source is important first of all, not just one spot, but boat edge, leading area and so on, need more work here for a good result. Mask by curvature as an example. wave_v03.hip

Hello magicians, Here is the AI for Artists tutorial for Houdini, which will help you to make the first steps in Machine Learning. We will create a Houdini scene to generate data for Machine Learning, train the Logistic Regression model with this data, and utilize the model to detect a 3D object type (if it is a Sphere or Cube). It is quite simple to replicate, yet fun, and has the potential to extend for similar tasks.

Try to play with inverse force to keep points inside volume. Pyroflip_RR_OD_v02.hip

@fencer - again thanks for your input into this scene - so much appreciated i thought i'd share a couple of versions... Heres the version using the setup adjustments you added thankyou! I've got less fractured pieces here and they're a bit thicker but the idea works. I quite like how the pieces dont seem to get flung outwards as much. One thing i did notice is that the simulation time seems to be quite slow - i dont know if this is because there is no proxy geometry being fetched in from the solver sop / colour-transfer area in the scene? Any ideas on this? But overall its worth the wait this is my original version that is pretty much a brute force sim.. a giant pile of fractured pieces resting and only activating at the point where hulk first hits the ground. You can the ground is cracked up close to the cam and the pieces seem a lot more "free". This one seems really quite heavy duty lol! test render of the old (2nd gif) simulation... still early days but its working fairly well for a nerd art fan film

I just cross fade them with a final frame near the end of the animation. Drop down a TimeShift node and pick your frame, then shape blend into that frame.

Here is one way to do it you can play inside the pop solver how much the particles live, etc fx_particle.hip

Just ran into this same issue- if anyone else has this problem-I fixed it by going into the parameter edit menu (the gear icon)- made the parameter invisible- clicked apply- then made it visibile again- clicked apply- and I got all 3 (xyz) parameters back

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. This list was started years ago, so some of the solutions may be dated. 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 Blazing Fast OpenCL Smoke Solver [PYTHON]Post Process OBJ Re-Write Upon Export 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!) [REDSHIFT] MTL To Redshift Material [REDSHIFT] Access CHOPs In Volume Material [REDSHIFT] Mesh Light Inherits Color [REDSHIFT] Color Smoke [REDSHIFT] FBX Import Helper [REDSHIFT] Terrain Instancer Height Field By Feature 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 [PYTHON] OP UNHIDE ALL (opunhide) Collision Deform Without Solver or Simulation Mograph Lines Around Geometry Waffle Cornetto Ice Cream Cone Ice Cream Cone Top 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 Rains Water Drip Surface Splash 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 Blood In Water Smoke Dissipates When Near Collision Object Whirlpool Mesh Surface Whirlpool Velocity Motion For FLIP Simple Bacteria Single Point Falling Dust Stream Flames Flow Outside Windows Gas Blend Density Example Localized Pyro Drag (smoke comes to a stop) Granular Sheet Ripping Post Process An Export (Post Write ROP Event) Corridor Ice Spread or Growth Set Velocity On Pieces When Glue Bonds Break Water Drops Along Surface Condensation Bottle Grains Snow or Wet Sand Starter Scene A Nice Little Dissolver Turn An Image Into Smoke Fading Ripples Grid Example Stranger Things Wall Effect Face Through Rubber Wall [PYTHON]Create Nurbs Hull Shelf Tool [PYTHON] Ramp Parameter [PYTHON] On Copy OF HDA or Node Select Outside Points Of Mesh, Honor Interior Holes Sparks Along Fuse With Smoke Umbrella Rig Melt FLIP UVs Tire Burn Out Smoke Sim Flip or Pyro Voxel Estimate Expression Motorcycle or Dirt Bike Kicks Up Sand Particles Push Points Out Of A Volume [PYTHON]Cellular Automata Cave Generator Punch Dent Impact Ripple Wrinkle VEX Rotate Packed Primitive Via Intrinsic Kohuei Nakama's Effect FLIP Fluid Inside Moving Container Particles Avoid Metaball Forces FLIP Divergence Setup FLIP Transfer Color Through Simulation To Surface Morph Between Two Static Shapes As Pyro Emits Constraint Based Car Suspension Pyro Smoke Gas Disturbs Velocity Wire Solver Random Size Self Colliding Cables Fast Cheap Simple Collision Deform CHOP Based Wobble For Animated Character Slow Motion FLIP Whaitewater Avoid Stepping In Fast Pyro Emission Fast Car Tires Smoke FLIP Fluid Fills Object Epic Share Of Softbody/Grain Setups (Must see!) Balloon, Pizza, Sail, Upres Shirt, Paint Brush Create Pop Grain Geometry On-The-Fly In A DOPs Solver Varying Length Trails VEX Based Geometry Transform Determine Volume Minimum and Maximum Values Grain Upres Example Animated pintoanimation For Cloth Sims Batch Render Folder Of OBJ files Vellum Weaving Cloth Fibers Knitting Kaleidoscopic Geometry UV Image Map To Points Or Hair Color Particles Like Trapcode Particular Flat Tank Boat Track With Whitewater Orthographic Angle Font Shadow Select Every Other Primitive or Face? Printer Spits Out Roll Of Paper Unroll Paper, Map, Plans, Scroll Simple Vellum L-System Plant Basic Cancer Cell 2D Vellum Solution Vellum Animated Zero Out Stiffness To Emulate Collapse Whitewater On Pre Deformed Wave [PYTHON] Menu Callback Change Node Color Extruded Voronoi With Scale Effector Multi Material RBD Building Fracture House Collapse Spin Vellum Cloth Whirlpool Vortex Trippy Organic Line Bend Design Logo Based Domino Layout Delete Outer Fracture Pieces, Keeping Inside Pieces UV Mapped Displaced Along Length Curly Curves Slow Particle Image Advection Nebula Saw Through VDB Like Butter Fuel Based Rocket Launch With Smoke Fuel Based Rocket Launch With Smoke [upres] Deform Pyro Along Path Bend Pyro Gas Repeat Solver With RBD Collision Raining Fuel Fire Bomb City Video Tutorial Pyro Cluster Setup (Animated Moving Fuel Source) [PYTHON] Mantra .MTL File Reader (creates new materials) Pyro Dampen By Distance FLIP Fluid Sweeps Away Crowd Ragdoll Gas Repeat Solver X-Men Mystique Feather Effect Camera Frustum Geometry Culling Vellum Extrude Shape Into Cloth Wire Web Constraint Setup Pyro Smoke Font Dissolve "Up In Smoke" Helicopter Landing With Vellum Grass and Dust or Smoke Another Thin Sheet Fluid Setup Color Rain Drops Over Surface Dual Smoke Object Wand Battle Custom GasDisturb node (easy to use) Hair Driven Grass Example File Pyro Smoke With Masked Turbulence Align High Resolution Mesh With Low Resolution RBD Simulation Streaky Portal Effect Height From Luma Cracking Glass Dome, Fracture VEX Noise Types FLIP Waterwheel Fracture Brick Wall Using UVs Vellum Stacked Torn Membranes Terrain Topographical Line Curves Prepare RBD Fracture For Unreal Alembic Export Growing Ivy Solver Fix For Intermittent FLIP Surfacing Issue Extensive RBD Fracturing Thread With HIP Files Peter Quint's Pop Streams Particle Example Fracture Geometry To Release Flip Fluid Inside Procedurally Reverse Normals Vellum Culling Voronoi Shape To Shape Transition Animated Scattering Accessing Parametric UVs On A Surface Organic Hallways/Corridors Through A Mesh Smoke Particle Dissolve Along One Axis Expanding Vellum Rings That Collide With One Another Read, Fetch, or Get SOP Attribute Inside Of DOPS Broad Splash When Object Enters Water Blendshape Crowd Example [PYTHON] Replace Packed Intrinsic Geometry From Another Source Rip/Tear Part Of Paper To Reveal And Roll Up After Effects Text Styles Cabling Mesh Surface Hanging Wires Or Cables Use Python Inside a Font Sop Brand Accurate Textures Using Karma XPU hScript asCode Microscopic Hair USD Attribute Equivalents For Preview Shader (i.e. Cd mangle) Vellum Peel Effect SOP Pyro Control Field Gas Disturbance Repair Geometry Self Intersection FLIP Follows Curve Long Winded Guide To Houdini Instancing Disable Simulations On Startup Tutorial HIP Library Use Google To Discover Attached HIP Files Useful Websites: Tokeru Houdini Houdini Vex Houdini Python Houdini Blueprints FX Thinking Rich Lord HIP Files iHoudini Qiita Ryoji Toadstorm Blog Eetu's HIP Of The Day Video Tutorials: Peter Quint Rohan Dalvi Ben Watts Design Yancy Lindquist Contained Liquids Moving Fem Thing Dent By Rigid Bodies Animating Font Profiles 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 Johhny Farmfield Vimeo SideFX Go Procedural

you gotta use pop wrangle or pop vop to bring that attribute/data from SOPs into DOPs then you can use it with Vex inside DOPs. popforce+bullet_FIX.hipnc

uv_transfer_with_seams.hip try a for each loop

Use the Snippet VOP

untitled.mp4 maybe you can just fake the part where its just rotating in the air like that. pop and noisey geo pop_surface_slider_ray_water_ball_attract_2.hip

There are several issues: If you look at your prim_ID attribute in "pointwrangle1" you can see, that it is always 0 (the primitive 0 is the lowest middle starting from the center -> so the values displayed are correct but probably not what you want). The reason for this (you initialize the attribute in pointwrangle1 while calling it -> to fix this you can capture the the primitive using xyzdist() as well) but on the other side, you are capturing the original geometry (overlapping) from the not overlapping geometry, which makes no sense in my opinion. What is wrong about doing the other way like in my example? @edit: here is another way capturing the position directly from carving Match_Carve_modA.hipnc

You can probably try to capture the u position of the parent prim using xyzdist() limiting to the Prim_ID you have defined. Once you have the u-parameter from the start and end point you can use the fit function (to fit them to 0-1). Match_Carve_mod.hipnc

Sorry, my bad. How about this? iteration_over_primitives_v02.hip

https://www.youtube.com/watch?v=YFttANQeq_o https://x.com/HoudiniSchool/status/1681333312445378561

After a couple of hours of testing, I found that blending the deformation in, instead of adding it, helped stabilize the simulation. For whatever reason, all the deformations had to be under the waterline for this to work. wave.hip This is what it looks like with a boat, in case this is useful to future people: Thanks for the reply Fencer. It does look fine, but in my testing on the boat deformations, that dip becomes very chaotic after 200 frames. But, help is always appreciated man

Hi to all of you. I am happy to be a part of this Odforce community As a passionate user of Houdini I am excited to dive into discussions about visual effects, 3D animation & all things Houdini related. I wish to get in touch with people who have similar interests to mine. I have participated in a number of discussion that have undoubtedly greatly helped me; I still want to share & learn as well as start my own conversation to answer my question and learn more. If there are any posts or resources that are suggested for new users. Please divulge me I am grateful.

You can use the PolyPath SOP to make a single open polygon with the correct vertex order out of the Intersection Analysis output, because Intersection Analysis doesn't output a single continuous polyline. After that you can use a Sort SOP set to "Point Sort: By Vertex Order" to transfer the correct order to the points.

Hi guys I started creating a series of brief tutorials covering specific tips and tricks for using Houdini features. So these tutorials are not meant to provide comprehensive explanations of the topics. Please subscribe to my YouTube channel for more. Houdini Tutorial: Attribute Paint re-cache method feature:

You can transfer a color to rbd and activate piece by it (If I understood what you need correctly). Same time keep deformation. shot_WRLDBRK_0196_scene_for_odforce_v01.hip

try vellum grains. untitled.mp4 vellum_grains_ice_cream.hip

@Damn_daniel Terrain_advection_v004.hipnc

Just look it up. That's one of the most famous nuclear test documented.

Jason Harmon.. trig grains audio Chops audiotrigF01.hiplc

Remapping an attribute so its maximum is 1.0: 1st point wrangle: setdetailattrib(0, 'height_max', f@height, "max"); 2nd point wrangle: f@height /= detail(0, 'height_max', 0);

Bumping this old thread in case anyone else finds themselves in a similar boat where they're drawing a blank on this technique and end up googling "Houdini noise transition". The trick is to first form your gradient using a value, in this case the x position along a grid... ...and then add noise to that value. For a deeper dive into this kind of thing, definitely check out this series of classes by Main Road Post and this brilliant page by Kiryha. Hope this helps.

To fill quadratic polygons with copies just take the square root of the intrinsic primitive area as point scale: int pt_add = addpoint(0, v@P); float area = primintrinsic(0, 'measuredarea', i@primnum); float scale = sqrt(area); setpointattrib(0, 'pscale', pt_add, scale, 'set'); removeprim(0, i@primnum, 1); KM_recursive_subd_001.hipnc

I'm sure you can't do it without an additional data. For example, is it possible to retain transform matrix on points of original geometry? Then yes, just multiply it by inverse. Dealing with object transforms is the most straightforward way, and you need only transform, simple box with some snapping techniques with desired transform is fine. Extract Transform OBJ. There is another nice method I didn't found in Houdini, maybe it will fit you. If you have at least two triangles, or any arbitrary 3 points transformed, of before-transform and after-transform states (for example, if you store rest position or if you could recreate it more or less exact), then you may easily calculate transform matrix between them using triangles's "local spaces" created from triangles's sides. Here the code for Primitive Wrangle (I used "0" as group, it runs only for first polygon) with two identical geometries on inputs, where second is arbitrarily transformed. // Create a basis from points of triangle. matrix3 basis_from_triangle(vector p1, p2, p3) { // Axes vectors. May not be orthogonal. vector X, Y, Z; Z = p2 - p1; X = p3 - p1; Y = normalize(cross(Z, X)) * length(p2 - p3); return set(X, Y, Z); } // Calculate rotation matrix rotating triangle ABC into triangle DEF. matrix3 rotation_between_triangles(vector a, b, c, d, e, f) { matrix3 basisABC, basisDEF; basisABC = basis_from_triangle(a, b, c); basisDEF = basis_from_triangle(d, e, f); return invert(basisABC) * basisDEF; } // Calculate transform matrix transforming triangle ABC into triangle DEF. matrix transform_between_triangles(vector a, b, c, d, e, f) { matrix transform = ident(); matrix3 r = rotation_between_triangles(a, b, c, d, e, f); transform *= r; translate(transform, d - a * transform); return transform; } 4@transform = transform_between_triangles(point(1, "P", primpoint(1, @primnum, 0)), point(1, "P", primpoint(1, @primnum, 1)), point(1, "P", primpoint(1, @primnum, 2)), point(0, "P", primpoint(0, @primnum, 0)), point(0, "P", primpoint(0, @primnum, 1)), point(0, "P", primpoint(0, @primnum, 2))); Now, transform points using Point Wrangle with second input as geometry, simply getting first primitive's transform attribute. @P *= matrix(prim(1, "transform", 0)); Or, being contemporary, Deformation Wrangle, because it is exactly why it was created. pos *= matrix(prim(1, "transform", 0)); It will properly transform attributes you need to have transformed. With Point Wrangle you need to use other wrangles to transform vertex normals or other attributes. Actually, for normals only there is special checkbox on Point Wrangle, and sometimes it works. betweentria.hipnc