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here is fixed version, one of main problems in your scene is that your bound that you use for cuting fields is not matching your cache sim domin, you need to think about that every sim first have small reseed boundry most of time 0.5, you need to remove that before doing any combine, and also when you are doing wwater sims blend_low_high_03.hipnc

Maybe this can help Blend surface - what i am doing is sample from low mesh position with attribut trasnfer on high res mesh, and then using bbox of high res sim domain, converting to volume, and finaly using it ask maks, then blending low_P and original high res P with that volume maks, so that high res mesh P blend into low res P and edges are matching| - then converting back to vdb and using as surface field for wwater or layer on for meshing Blend vel - same idea like surface - resample low res vel to match high res vel, bring them both into vop, with same maks, and just blend then like surf field, and export as new vel Thats all, its very simple idea, it was more to make something working for my tests Hope this help

@Sherzod Marcel Padilla (Filament-Based-Plasma - Siggraph 2022) search ..and files included for Houdini..Have Fun.

Frame 141.... a quick trail Bubbles_Foam_wire_vdb.hip

Group the points by bounds, before you copy to points, then break off a network line and add a delete node that references the points in that group. Choose Delete Non- Selected, then have your font node reference the result of that delete instead. Which will be all the points in the box. You'd have to animate the box on the group node, however.

try the peak sop. its easy to use rbd_soft_constraint_infection_preview.hip groundbreak.mp4

Hi, In his scene there was few problems with vdb operation, attribute transfer stuff. His scene is very small, i meen upres region is close to same low res sim, so it can be tricky to blend all edges. This is fixed version blend_low_high_02.hipnc

I played around with that and got some help on a Discord. It's hard to see in the video, but inside the VOP blending the @vel, there are two types of volume samples. The top one is a volumesamplev (used to sample vectors such as velocity) and the bottom one is a volumesample (used to sample floats such as density). Try swapping your top volumesample node with a volumesamplev.

It would be nice to have a new Houdini Engine licensing policies. Today if you are a small company with floating license. You have to pay $795 per year per machine which is perfectly fine. Paying a fee when you do use houdini in batch mode, is perfectly fair. You need to use mantra / karma / or any Dop / Sop processing on your farm it's ok to pay the right to access Houdini. But when you need to just render a scene in an external engine, a scene that just contain loaders to .bgeo / .abc / .vdb files in Arnold / Vray / Redshift / Octane, i don't find fair to have to pay the full price to just open the scene and send it to the engine on the renderfarm. I just don't render or process anything with houdini, i just send my scene to the external render. Thus each time i said in place i work that it would be better to switch the render to houdini and stop using the other software i would not name, i always get this answer. How much it cost ? And in fact when using arnold for exemple which is $500 per year, you have to add the $795 cost to each arnold license, thus $1295. so it cost a lot More. So they always said, why do you want to pay 1295$ per machine while it cost only $500 with the other software. Why do we should pay the right to send our scene on the farm $795 ? I could do full .ass export for each scene but in small shops where there are not strong pipe dev or houdini dev it's rarely an option. And when company use a mix of render engine you add another layer of complexity. My point is that it would be great to have - Houdini Engine , an engine that process data or render image using houdini tech and that cost $795 for accessing this technology - Houdini Batch which basically would only open a scene and let the external render engine render it, be free or cost much less , because it do much less. Cheers

you can use the sweep node or use point split point_and_prim_cound_changes.hiplc

Thank you so much - this is really useful. Appreciate your time. Rich!

Hi, you can start with a grid for example (just columns) and apply deformations on each line. Once you have the deformation you can apply the sweep node (with square profile) to create the geometry. If interested here is an example file using some VEX for the deformation. wave_through_lines.hipnc

can you provide a scene for us? i would like to see it !

you can for example change the mass/density of the falling objects, you can change substeps/constraint_iterations in solver, or adding attatch constraints to the net. vellum_ball_into_net_stiffness.hip

you can merge with polypath or joint node. But guess this isnt the right way. you can simulate right away with stitch for example Merge Primitives.hip

Hi Karen the reason is because it fails to find a primitive when shooting a ray in the normals direction since your target collision only has 1 primitive (1 face in the middle). What you could do is drop a convertline node before the ray to break your target's edges into 4 primitives, that should fix the issue. Added VEX version as a bonus ray_normal.hiplc

use a sop solver in constraint network rbd_break_frame.hip

or in for each different_peak_for_each_group_point.hiplc

FFX Geometry Explainer is an assistive HDA for Educators, and DIY learners. As a beginner, have you struggled with understanding how Vertex, Point, Primitive, Detail, UV Seam, Edges, Half-Edges, Normals, Normal winding, and Shared/Unshared points relate in Houdini? This HDA should help. https://davidtorno.gumroad.com/l/geometryexplainer For Educators, there is an unlocked option, so you can dive into the tool build and customize it to your specific needs if you like. For learners, there's a cheaper basic version that is locked, but has all the same learning info.

@Atom It did exactly what I wanted it to do. Thank you so much for providing the idea!

You can use the hScript npoints() function for that. Make sure to surround the function with the backticks so the font node will evaluate the function, and not display it.

If you mean something like this, I added a hip file to give a hint. I first create a rbd sim. Then I use the result of the rbd and fill it with points which then get the velocity of the original simulated geo. And finally only at one frame the points are used in a pop source node in the flip dop network. Of course for multiple rbd's you will need to autmate some parts and get the collision frame somehow. Hope this helps a bit. rbdtoflip.mp4 rbdtoflip.hiplc

@Ultraman. Try to make something of this File.. skinWeight.hipnc

If you haven't already, you might want to post this question on the SideFX "Houdini Engine for Unreal" forum as well - https://www.sidefx.com/forum/51/

It looks like a custom function inside the Vellum Object. Unlock those HDAs and poke around. You could try taking the code and placing it inside a GeometryWrangle running over primitives bound to the constraint geometry.

@christianl013 if you search here You can found also ,here its something 8 ways to put points onto the geo surface

I just tried exactly what I suggested and it works fully compiled, but it's a lot of work to replace all the expressions and many of the Heightfield nodes are not built to be compilable either, so it's not for the faint of heart to make this work.

vellum_ropes_curves_tension__pin_animated.hip

@gavotte here its a file from Nick Wood that you can Modify easily .. Maybe it Helps! bball_hoop.hiplc

As @Atom mentioned, you don't have to use setpointattib in this case. But just for completeness, it was erroring because the order of arguments is wrong and you included the return type in the function call. It should be like this: setpointattrib ( 0,"start", @ptnum, i[]@neigh );

You don't have to use a setpointattrib on input 0, because you're already running over those points. You can assign the attribute directly. i@start = @neigh[1];

Just wondering best approach to move diagonal(or any movement) and rotate with connections with specific name and relationship? Thanx.. tangram.hiplc

can be useful on any motion(trans-scale to 0.01) ..Like always <3 Asia . collEm.hiplc

A curve has UV, maybe try to use it on shader level. beam_v01.hip

@Librarian You could also add a link or the article's title, instead of writing "Asia". 60% of the word's population is in Asia, so that doesn't really narrow it down.

Glad you like it. I'd recommend rendering only the particles instead of VDBs. It's a lot faster and can get way more detailed.

Just posting this here in case anyone is interested. Based on this job posting it looks like SideFX has some big plans for COPs that look pretty exciting. https://sidefx.bamboohr.com/careers/90

As a majority shareholder in google, I'll get them to bow to my will. One sec. . . . . . . No.. I'm told I'm not a majority shareholder. What's weird is that used to work. I'll snoop around and see what the deal is.

Check this curlyswirly_v01.hipnc

All done in Houdini except for the rigging/animation, although we're going to see about changing that up for the next one. He's going to have his own YouTube channel at some point. Bear vlogging is where it's at these days.

I saw a scene on Houdini Blueprints depicting Crag walking through a plane. I thought the concept was nice, but the implementation was missing a feature. This is my rebuild of that scene. The background is now UV mapped in the 16:9 ratio, so you could apply footage to it. The Crag geometry is unpacked to provide a better contour tracking to the geometry shape. Other packed RBDs could take the place of Crag in this setup. The main feature I added was the addition of a primitive group around the edge where the transition takes place. This will allow a separate material to be applied, such as a glow, while still maintaining the background plate. ap_hdbp_stepping_through_portal_100722.hiplc

Benchmarking Ray Tracing for Realistic Light Transport Algorithms For those interested in low-level raytracing performance, a comparison of acceleration structures. http://bwfirt.sourceforge.net/

Hey folks, proud to present LYNX Tools, a collection of production proven open source tools to accelerate your workflows! All mentioned tools are free to download via the links below and are licensed with a full HoudiniFX license. All Houdini Assets have complete Houdini native documentation available. Repository: https://github.com/LucaScheller/VFX-LYNX Lastest stable release: https://github.com/LucaScheller/VFX-LYNX/releases Please give them a test drive, so we can improve them further Roadmap | https://github.com/LucaScheller/VFX-LYNX/projects/1 So far there are three tools: LYNX_force_general | Tweak your sims with this all purpose & intuitive force field. Built to mimic force fields in other DCC applications, but with support for more features and a natural Houdini user experience. https://www.lucascheller.de/vfx/2019/03/24/vfx-lynx-houdini-force-general-asset/ LYNX_fabric | Create fabric/weave patterns with ease. Perfect for creating that holiday sweater you never wanted. https://www.lucascheller.de/vfx/2019/03/16/vfx-lynx-houdini-fabric-asset/ LYNX_velocity | Get control of your velocities via an intuitive UI or groom them for absolute fine tuned control. https://www.lucascheller.de/vfx/2018/11/01/vfx-lynx-houdini-velocity-asset/ More info on my website, including full release logs: https://www.lucascheller.de/blog/ Houdini User Group Munich Presentation: https://vimeo.com/334887452

I worked my way through Edmond's tutorial on how to allow flip droplet particles to escape their boundary. The nodes modified inside of the unlocked HDAs are marked in RED. ap_flip_droplets_escape_021622.hiplc

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

Hello Friend. This works, the solution is accurate. We are grateful to bring us this gift!

Second constraint must be a constant vector like @up. They define static reference frame for the changing @aim vector. // Point wrangle. #define PI 3.1415926535897932384 float angle = acos(dot(v@up, v@aim)); int first_half = sign(dot(v@z, cross(v@up, v@aim))) >= 0; angle = first_half ? angle : 2*PI - angle; @angle = degrees(angle); circle_angle.hipnc

Yep, the new polyextrude uses attributes rather than local variables. On the 'local control' tab you'll find toggles to enable attribute overrides for various properties. To randomise the distance, turn on 'zscale', and make sure you have a randomized @zscale attribute on the primitives feeding the extrude. Attached 2 ways to do this, one with a prim wrangle, the other with an attribute randomize sop. rand_polyextrude.hipnc

Attached a project with hip file containing a motion blur aov, your alembic (in abc) and a nuke script (in comp) with a working vector blur setup. (credit to the guys at work for figuring this out) moblur.zip

Quoting my self from the TD Academy thread, here are some links on OpenCourseWare I got from CGTalk. Opencorseware search: ocwsearch.com --------------------------------- khanacademy.org academicearth.org MIT Stanford Princeton Berkeley and iTunes Berkeley Purdue Carnegie Mellon Utah State Tufts Johns Hopkins School of Public Health University of Washington Computer Science & Engineering Harvard Openlearn Connexions Wikiversity and Wikibooks Lamar University Math Course *edit - I'll make updates as more links are posted