Adding Motion FX Presets

Adding Houdini Motion FX Presets to Paremeters

So this a really simplistic video I made back in Houdini 14 or 15 showing how to add Motion FX (CHOPS) presets to a parameter channel. It’s really more of a sample video than a tutorial. I even throw in some ch() and stamp() functions. Sorry about the lack of audio and playback. It was a spur of the moment type thing. It actually does not play this slow in the viewport. Hopefully I work my way up to actually doing proper videos, but we shall see.


Houdini Bag of Tricks

Here is a Houdini bag of tricks that contains tips that were on the old site but I decided to package them up. Most are just small workflow tips or hotkeys but can be quite handy. VEX Snippets If you’re been playing with POP nodes, I’m sure you have noticed that little scary checkbox that says Use VEXpressions. Maybe you’ve dropped down one of the powerful Wrangle nodes but you decided you were not ready to tackle that little monster. Well, Side Effects has packaged up some nice VEXpression snippets to help you out. Hidden away in the top right corner is a drop down […]

Default Web Browser for The Houdini Docs

Default Web Browser for The Houdini Docs

Is the built in Houdini help browser dragging you down? On OS X it’s a bit slow for my taste. On Windows and Linux it works well but maybe you’re like me who loads the documentation on the Side Effect server just because it’s faster in your default Web browser. Maybe not. Regardless, using your good old Web browser for the Houdini docs has a couple of advantages. Let me show you how to user your default Web browser for the Houdini docs instead of the built in Houdini browser. Built-in Web Browser Houdini has fantastic documentation and and each node gives you access to […]

VOP Output Names

Show Full Input and Output Names on VOP Nodes

So we all know about Houdini’s dynamic duo nodes VEX and VOP. For those unfamiliar with programming, VEX nodes may be a bit intimidating. However, this is where VOP nodes come to the rescue. Think of VOPs as visual programming. If your coming at Houdini from a Cinema 4D angle, think Xpresso. Now I’m not saying working with VOPS is a walk in the park but it’s a nice entry into the world of VEX. Check out some of the great tutorials with extensive use of them over at Entagma if you want some practice. Here is a tip on how to show full […]

HScript Memory Command

Checking Memory Usage In Houdini

This may not be the most exciting or life changing Houdini tip you will come across. I’ve been developing some scripts that need to check the Houdini memory footprint. I figured this bit of information may come in handy for someone out there. There are specialized applications and utilities at the OS level that provide this information. However, I needed something I could access programatically. As luck would have it, checking memory usage in Houdini is built right in. Memory Usage I mentioned while developing some tools, I needed to check the memory usage in Houdini for some conditional statements. My initial thoughts […]

The Geometry Object

The Geometry Object

So you have decided to learn Houdini. You have a new scene open and you drop down a box. Now you want to change the divisions of the box. You see that there are several tabs in the parameter window for the box such as Transform, Material, Render, Misc but nowhere do you see the ability to change the subdivisions of the box. What gives? Welcome to the Geometry Object. Object Level One thing you have to remember is that in Houdini, when you drop down a Box or Sphere node at the object network level, that top level node is just a container for your actual geometry. […]

Toggle Safe Area Shelf Item

Creating a Video Safe Area Toggle Shelf Tool

Since my work is primarily for video and interactive domains, I have a need to check my video safe areas often. Not a big deal. Almost every animation application has the ability to toggle the safe area guides on or off. Houdini is no different, however, it takes a few steps. Enough to be a bit annoying. In this post I’m going to show how I went about creating a shelf tool that toggles the safe area guides on or off. Shelf Sets, Tabs, & Tools The shelf is the strip of icons along the top of the main window and is composed […]

Drag and Drop Tools

Drag and Drop Tools

Since I’m riding the Python boat, before I get back to some more Python in Houdini, I wanted to throw out this tip for those wanting to create custom tools and to further wet your appetite a little bit. After all, this is how it all starts. Let me show how easy it is to just drag and drop tools on to your shelves. Shelf Tools The preferred way to create reusable tools in Houdini is by creating an HDA or Houdini Digital Asset. Oooh! Fancy! But what if you just need a temporary thing. Something rough that is just meant for […]


Using the Op Operator

I’m sure you’ve seen the op operator while on your Houdini tutorial journeys or rummaging through .hip files. It usually goes something like this: op:/path/to/node Cryptic stuff. I know, I was like ”WTF is that?” when I first saw it. Turns out it’s rather handy. What is cool about the op operator is that it allows you to grab live data from another node elsewhere in your scene. Let’s try to break it down with an example of sorts. Beer with A Straw Imagine you’re on a beach and there are several bars around. One bar in particular changes its selection of premium […]

Disable Primary Rays in Houdini

How to Disable Primary Rays in Houdini

A common thing to do in 3D workflows is to make an object invisible to the render engine. Either completely invisible or invisible but still cast shadows and reflections. In geek parlance, no primary rays but secondary rays. If you are a Cinema 4D user, you can achieve this through the Seen by Camera option in a Compositing Tag. Houdini users are accustomed to the Phantom option. At least this is how I came to learn it by. So how to we disable primary rays in Houdini? Phantoms Objects In early versions of Houdini, you could disable primary rays by checking on the Phantom […]

Inspecting The Houdini hou Module

Python Parameter Expressions III: Auto Import

So we covered basic Python expressions and how to work with custom functions. Alright, that’s nice and dandy but how do we get Houdini to load our custom functions so they are always available? Custom functions can auto load in a couple of ways. You need to setup a few of things but it’s quite straightforward. Today, we will look at how to auto import our functions so they are always available. If you need to catch up, here are the previous posts: Part I – Python Parameter Expressions I: Basics Part II – Python Parameter Expressions II: Custom Functions Part III – Python Parameter Expressions III: Auto […]


Show Hidden Files and Thumbnails

Being a UNIX nerd, I love navigating the file system through the shell. I’m partial to the shell because this is where I learned the fundamentals of programming. It also makes me feel like I’m controlling the Matrix. Just like David Hasselhoff would. One thing in Houdini that I kept wondering about was why I couldn’t see hidden files when I had an Open Dialogue window open. This is despite having Show Hidden Files checked in the Preferences. Here is how to show hidden files and thumbnails in Houdini. Open Sesame I accidentally stumbled across this little gem. When you open a file […]