jkunz07

Here's a stream I did over the weekend which demonstrates my process for making one of these animations. The file is linked in the description. Would've liked to push more of the steps into VEX (like the copy and transform, etc.). If anyone builds off of this or finds better ways to do things I'd love to hear about it. Follow me here: https://www.twitch.tv/johnkunz for more streams!

Hello! I'm starting a twitch dot television channel and will be streaming Houdini training content. I've worked at several large VFX and advertising studios as well as taught Houdini classes at Academy of Art university. I'm hoping I can reach a larger audience through Twitch as well as the idea that people viewing the stream can participate by asking questions and providing feedback in real time. This is my channel: https://www.twitch.tv/johnkunz My first stream will be starting on Sunday (Jan 26th) @ 1pm PST. If you follow my channel (it's free ), you'll get an email notification whenever I start a stream. I'll be going over this project I recently finished https://www.behance.net/gallery/90705071/Geometric-Landscapes showing how I built things (VOPs, packed prims, Redshift render) and why I set things up the way I did. Some of the images I made are shown below. Please come by this Sunday with any questions or ideas you might have!

I would recommend python/hython for this task because you mention your dealing with many files. Python is much better at working with directories, many files on disk and databases then hscript/hbatch is.

You can do something like: echo $_HIP_SAVEVERSION > $TEMP/$HIPNAME.txt This will put the version number of Houdini that the file was last saved with into a .txt file of the same name as the .hip file your currently checking (In the /tmp directory of your OS).

You can set visibility per face at the SOP level: http://mrkunz.com/blog/12-08-2016_Export-Alembic-geomtery-from-Houdini-utilizing-the-visibility-property.html Other packages like Maya and Vray will support this out of the box and hide the faces both in the viewport and during rendering. Mantra doesn't hide invisible faces by default, but you could do many things to hide them, either just blast the hidden faces group or assign a kind of pass thru zero opacity invisible type shadier to the hidden face group

This is an issue with the OpenVDB code being updated to 5.0, when I asked SideFX about it a while back they said they have let the OpenVDB team know about this issue.

float eps = chf('epsilon'); // Default 0.01 float magnitude = chf('magnitude'); // Default 1.0 vector p = v@P; // Noise Initial Position float freq = 1.0; // Noise Frequency vector offset = chv('offset'); // Noise Offset p = p * freq - offset; // Final Noise Position vector dx = {0, 0, 0}; dx[0] = eps; vector dy = {0, 0, 0}; dy[1] = eps; vector dz = {0, 0, 0}; dz[2] = eps; vector fxdxn; vector fxdxp; vector fxdyn; vector fxdyp; vector fxdzn; vector fxdzp; // Evaluate the noise in a local neighborhood for finite differences fxdxn = noise(p-dx); fxdxp = noise(p+dx); fxdyn = noise(p-dy); fxdyp = noise(p+dy); fxdzn = noise(p-dz); fxdzp = noise(p+dz); // Compute curl from the cross product vector curl; curl[0] = (fxdyp[2] - fxdyn[2]) - (fxdzp[1] - fxdzn[1]); curl[1] = (fxdzp[0] - fxdzn[0]) - (fxdxp[2] - fxdxn[2]); curl[2] = (fxdxp[1] - fxdxn[1]) - (fxdyp[0] - fxdyn[0]); float scale = magnitude * (1.0 / (2.0 * eps)); curl *= scale; @P += curl; If it's helpful, here's what a basic curl noise function looks like. You could replace the noise() calls with whichever scalar noise you prefer.

Those are used to sample finite differences of the noise, in order to find the gradient vector of the scalar noise.

You could add a detail attribute that get's used to toggle a switch node, bypassing the node you'd like to disable.

This thread is a good read through for getting faster settings

It should work fine in a standard vellum sim clothvortex.hipnc

https://www.sidefx.com/docs/houdini/vex/lang.html#dot-operator

There is also the preflight scene option (Use the Render ▸ Preflight menu item to find references in the current scene file to resources outside the project)

You can use __display_sop__ or __render_sop__ in the path instead of the name of a real surface node name to have Houdini use whatever node has the display flag or render flag.