Tag Archives: Live Performance

Understanding Referencing Part II | TouchDesigner

I love me some referencing. The more you work with TouchDesigner, the more you’ll find that you need a solid understanding of how referencing connects the various parts of your network. Better still is getting a better handle on how Python scripting works in TouchDesigner – especially dot notation. At the heart of what we’re after is making sure that our networks can start to feel a little more interconnected. Hard coding values makes for tedious programming, especially if you’re building something you’d like to reuse. By starting to think about how to build some logic into the system we’re making we begin to build reusable tools. If you’re still getting a handle on how referencing works, then it’s a good idea to get started here (Understanding Referencing) to get your bearings.

Let’s start with a simple example. I’ve got five images that I’d like to cycle through when I click a button. I know that I can use a Count CHOP and a Switch TOP to help with this but how can I make it so that my Count CHOP knows when I add another input to my Switch TOP? In a perfect world I could add or remove images or movies, and the network would just “know” what was going on, right? So how can we program something like this? Let’s start by taking a moment to visit my favorite part of working with TouchDesigner, the wiki. Specifically we need to look at our Switch TOP’s page.

The most important part of this page for us today is here at the top where it says “switchTOP_Class” next to the Python symbol. In object-oriented programming a class is a kind of “extensible template for creating objects.” The exciting part of knowing this is that a class comes with all sorts of methods and values that we can quickly call when scripting. With that in mind let’s take a closer look at the Switch TOP Class page. At this point you’re either beside yourself with excitement, or weeping with confusion. Let’s take a look at a quick example, and see if we can make some sense out of what we’re reading.

One of the first things on the Switch TOP Class page is a sentence that says “This class inherits from the TOP class.” This means that there are several things that work for the Switch TOP that also work for all TOPs. This means we can practice on a regular movie in TOP, and what we learn should also work for our Switch TOP. Okay, let’s open up a new network in TouchDesigner, and let’s add a movie in TOP and a Text DAT. We’ll also need to open up our Textport.

When you open your textport you should see a floating window that looks like this:

Great! With your Movie In TOP, Text DAT, and Textport you should be looking at something like this:

In our Text DAT we’re going to write a very simple little script that’s going to print in our textport. In Python we can print something to the textport with the command print(). Whatever we put in the parenthesis gets printed to the textport. You can practice this in the textport, just make sure that you use quotes around your text. For example:

print(“hello world”)

We can also complete this same operation using our text DAT. In the text DAT write:

print(“hello world”)

Now right click on the DAT, and select “Run Script” from the drop down menu. You should see the text appear in your textport:

Congratulations, you just ran a Python Script from a Text DAT. We’re going to use our ability to print to the textport to learn a few more things about our TOP class. We should still have a Movie In TOP in our network. My Movie In TOP is called “moviein1”, knowing the name of our operators is how we call point to them when we’re referencing. Looking back to the general TOP Class Wiki Page, I can see that there’s a member called width and one called height.

For this next step we’re going to use dot notation to get to the width and height information about our operator. For example, I can get that information by starting with the operator name, followed by a dot, followed by the member I want:

op(‘moviein1’).width

Let’s copy that exact line of code into our Text DAT. Next right click, and select Run Script. Nothing happened… what gives?! In this case, just because we asked for that value, doesn’t mean that TouchDesigner knew that we wanted it to be printed to the text port. In order to see these values in the textport we need to encapsulate our script in the print command. When you do this, you should have a script that looks like this:

print(op(‘moviein1’).width)

Now if you run the script you should see:

Let’s try one more. Let’s add one more line of code:

print(op(‘moviein1’).height)

Let’s run the script one more time and you should have something that looks like this:

Believe it or not, we just made some huge progress. Understanding how dot notation works gives you access to a HUGE treasure trove of information that you can use when scripting or writing references.

Let’s return to our example and see if we can’t use what we’ve just learned. Let’s start by adding a few things to our network. I’m going to add five Text TOPs, and I’m going to set them to be the numbers 1 – 5. Next I’m going to wire all of those to a Switch TOP, and then finally to a Null TOP,

Now let’s add a Text DAT to our network, and then take a quick moment to go back to our Switch TOP Class Page. Of particular interest to me is the Connections subsection:

Using what we just learned, write the following script into your text DAT:

print(op(‘switch1’).inputs)

When you run this script you should see something like this:

Well, that doesn’t look useful at all, does it? In fact, it’s tremendously useful! Python uses lists to store information, and what we’ve printed out is a list of connections to the Switch TOP. We don’t really want all of this information that we’re getting about the inputs, we just want to know how many connections there are. As luck would have it, there’s a way to get just that information. In Python we can ask for the length (the number of entries) of a list with the len() command. Alright, let’s make a quick change to our script and add the length command. You should have a script now that looks like this:

print(len(op(‘switch1’).inputs))

When you run the script you should see this:

Alright! Now we can start to really make some magic happen. Using .inputs and the len() command we’re able to now see the number of connections to our switch TOP. If you disconnect one of the inputs and run the command again you’ll see the number go down. Add a few more inputs, run the command, and you’ll see the number go up.

How do we use this? Okay, well let’s think back to where we started. We want to use a button to toggle through all of our inputs, and then cycle back to the front of the line. Let’s add a Button component to our Network, and a Count CHOP. Make sure to wire the Button to the top most input on the Count CHOP:

Let’s also make sure that the button is set to momentary:

Looking at our Count CHOP we want to set the Limit Method to “Loop Min/Max.” For the Limit Maximum value we’re going to use the script that we just wrote (only without the print command). We’re also going to subtract 1 from that number. We do this because 0 is still a valid input number for our switch, so while there are five total inputs those are associated with the numbers 0 1 2 3 4. The reference in the Limit Maximum field should look like this:

len(op(‘switch1’).inputs) – 1

Your Count CHOP parameters dialog should look something like this:

And now we have a little bit of black magic happening. If you add more inputs to your switch you’ll see the Limit Maximum number go up automatically, remove some inputs, and you’ll see it go down. Clicking on the button should cycle you through all of the inputs:

Now you know a little more about referencing, dot notation, and how to find more information in the wiki. Happy programming!

Check out the TOE file if you’d like to see what I made: Referencing Part 2

Let’s Make this Table Data Move | TouchDesigner

Working with live streaming data is about as good as it gets when it comes to programming – this is especially true if you’re working on a project that looks to create a recognizable relationship between live data and media. What, then, is a person to do when placed in a situation without access to a live source of data? Whatever the project, the best way to tackle this problem is to find a source of prerecorded information. If you’re working on something like motion tracking, using a pre-recorded video is an excellent solution to this problem. What about sensors that aren’t image based? What if I’m dealing with a series of floats? What happens if those floats just come to me in a table? How can I take a series of recorded data points that live in an text file and make them move? That’s exactly one of the problems that came up for me recently, and I’ve got a handy trick that will make it easy to work with a data set in a table as though it were streaming into your TouchDesigner network live.

To get started, we need a file with some data in it. I made a quick spreadsheet with two columns. One starts at 0.01 and goes up to 1, awhile the other column starts at .99 and counts down to 0. If you’re following along, you can download that text file here (tabledata). In broad terms, what were going to make is a simple network of operators that moves through a table, pulling one row of data at a time, and then converting that table information into CHOP data. We can see where we’re headed if we look at our whole completed network:

So what’s happening here? In the DAT called “data” we have a table of recorded values. Next I use a select to remove the header row from the data, and another select to move through the rows of data. Using another table, a transpose, and a merge gives us a table that’s easy to convert into a CHOP. Now that we have a general sense of what’s happening in this network, let’s dig-in and get to work.

We’ll start by adding a Table DAT to an empty network. Rather than entering data by hand, we can instead just point TouchDesigner to a file that we want it to use. In the Table DAT’s parameters dialogue we’ll click on the plus button to the right of the “file” field and then locate the file that we’re looking to use.

In order to see our table data we need to click on the button “Reload File” so that our table will be populated with the information from the file that we’re using. Next we’re going to use a few Select DATs to manipulate the contents of our table. We’re going to use the first select to remove the header row of our table. To set this up, we’ll set our select to extract rows by index, starting at 1.

You’ll also notice that specifying that we’re extracting rows by index turns on a End Row Index value that’s driven by an expression (me.inputs[0].numRows – 1). We’re going to use the logic from this expression a little later on, so tuck that into the back of your mind for just a moment.

Next we’ll use another Select Table to move through the rows of our table. In adding another Select, let’s again set it up to extract Rows by Index. This time, however, we’re going to change the value of the start row and end row index to be the same. Doing things, you should notice that we get only one row of our table. Try changing the values of these parameters – as long as both fields contain the same number you’ll see only one row of information. We’ll animate that in just a moment taking advantage of this.

The next operator that we’ll add to this network is a Transpose DAT. A transpose will change rows into columns, giving us a result that’s two rows, rather than two columns of data.

While just these changing values are ultimately what I’m after, I would also like my values to have names. To do this I’m going to add another table DAT, creating two rows: xPos and yPos. I’m going to use a Merge DAT to combine these two tables – to make this work properly we’ll need to set the Merge to append columns. When we’re doing we should have something that looks like this:

Alright, not that we have our DAT string’s set up, let’s animate this table, and look at how to get some CHOP data out of these DATs. First let’s start by adding a Constant CHOP to our network. Let’s give our first channel a useful name, and then call our absolute frame count (me.time.absFrame).

Why use absolute frame? I’d like a steadily increasing integer that can be used to drive our progression through the rows of our table. Our absolute frame is an excellent candidate for this need – except that I don’t want to exceed the maximum number of rows in my table. To do this let’s add a Limit CHOP. First up I’ll need to set this Operator to Loop, I’ll also want to set this operator to start at 0 (Minimum).

For the maximum value, I want to use the total number of rows in our second table (the table that contained only data, without a header). I could hard-code this by entering 200 into the Maximum parameter of our Limit, but then I have to change this number whenever my table changes. A better solution would be to use an expression to pull this number from the table in question – which is exactly what that expression we saw earlier does. The expression we want to use then for our Maximum parameter is: op(‘select1’).numRows.

Now it’s the moment we’ve been waiting for. Lets make that table move! To do this we’ll use the row counter in to drive our location in our table – we’ll write some relative references in our select2 DAT to make this happen. In the Start Row and End Row Index values let’s use the reference op(‘limit1’)[‘row’] to drive the change in our table.

The last step here is to add a DAT to CHOP to our network. We’ll add this at the end of our network, and drag the target DAT onto the CHOP.

There we have it. We’ve just taken a static table full of data, and turned it into a channel data that changes over time. For extra credit, add a Trail CHOP to the DAT to see what your data looks like.

Geometric Landscapes | TouchDesigner

Working on a new piece to premiere in Mexico I spent a lot of time experimenting with creating landscapes and backgrounds. Searching for a way into this exploration I wanted to play with the idea of instancing objects in 3D space, and the illusion of moving and shifting planes in space. This is already a popular visual style, and I was wanted to try my hand at exploring what it might look like to make something like this in TouchDesigner.

I’ve talked about instancing before, and so this challenge seemed like something that would be both fun, and interesting to play with. I also wanted something that mixed material methods – shaded, flat, and wire frame in appearance. Let’s take a look at how we can making something interesting happen using these ideas as a starting point.

Rendering is going to make or break us when thinking about how to set up this project, with that in mind it’s important to remember that a typcially rendering set-up needs something to be rendered (some geometry), a perspective from which to draw the object(s) (a camera), and a light source (a light, we don’t always need a light but as a rule of thumb it’s good to think that we need one). Our Geometry, Light, and Camera are all components, while our render operator is a Texture Operator (TOP). As a point of reference, here’s what a generic rendering set-up looks like:

We can tell our Render TOP to look at multiple Geometry Components, in the same network, or we can nest our active surfaces inside of a single GEO. Much of this depends on what you’re looking to create. The most important thing to consider is that surfaces operators (SOPs) are computed on the CPU unless placed inside of Geometry COMP – placed inside of a Geo they’re computed on the GPU instead. This makes a huge difference in your performance, and as a best practice it’s good to place any rendered geometry inside of a Geo.

Now let’s take a look at what our rendering set-up is going to look like for making our geometric landscape:

Here we can see that we have a similar set-up on the left – a light, a geo, a camera, and a Render TOP. On the right I’ve got the geometry viewer open so we can see a little more about the relationship in the scene of the camera, light, and geometry. We can see that the camera is set above our geometry looking down, we can also see that we have a cone light set-up with a wide angle and a wide delta.

Now that we have a general sense of what we’re making let’s dig-in and make something interesting.

Lets start with an empty network. Lets start by adding a Geo to our network.

To get started we’ll need to dive inside of geo to start making some changes. You can do this by double clicking on the Geo, using the quick key “i” (shortcut for inside), or by scroll wheel zooming into your geo. Inside our Geo we’ll see a torus that has it’s render and display flag set (the small blue and purple circles on the surface operator).

Inside of our geo let’s start by frist deleting the Torus SOP. Next let’s add a Grid SOP. Our grid is going to act the key generative element for us inside of this network – it’s going to give our surface its wire texture, the shading on the surface, and the location of where our spheres get placed. Our Grid is the central piece of what we’re making, and we’ll how in just a bit. Once we’ve added a grid to our network, we need to make a few changes to some its properties. First we want to make sure that it’s set to be a Polygon for Primitive type; we want to make sure that our orientation is set to ZX Plane; finally we want to change the size to 20 x 20.

Next we’ll connect our Gird SOP to a Noise SOP. We’re going to use the Noise SOP to drive some of the shifting locations of the points in our grid. Before we move on, let’s make one quick change, On the Transform page in the Noise SOP’s parameter’s we can see that the translate z parameter is set to change with the second count of our project – me.time.seconds. This is excellent, and it keeps our noise animated over time, but it also means that we’re only working with 600 samples (in a default TouchDesigner network) because me.time.seconds is locked to our timeline. If, instead, we want noise that doesn’t have a hiccup every 10 seconds, we can instead use the call me.time.absSeconds. This uses the absolute number of seconds that TouchDesigner has been running to drive the transformations in the noise SOP. It’s a small change, but makes for a nicer look (at least in my opinion).

Next we’ll add a Material SOP to the our network. Our material SOP is going to allow us to assign a material to our grid. We’ll do this by also adding a Wireframe Material to our network. Before we assign our wireframe to our material we should see something like this:

To assign the wireframe to the material, we’re just going to drag and drop the MAT onto the SOP.

Finally, we’re going to end this string by adding a Null SOP, making sure to turn on the render and display flags.

At this point we’ve made the Wireframe outlined elements of our grid. We’re now going to use the same data stream that we’ve already programmed to help us create a another layer of texture, and to create the locations for our spheres. Let’s start by adding our spheres to the network. To do this we’re going to do some instancing. When we’re instancing we need some location information for where to generate the copies of our source geometry. To get this information we’re going to use a SOP to CHOP to convert our SOP information into CHOP data.

Now before we move on we need to change gears for just a moment. What we’re going to do next is to add another Geo inside of our current Geo – in Russian Nesting Doll Fashion. Why? Well, we’re going to do this in order to take advantage of the Geo’s ability to instance. Why not use the Copy SOP? I love me some Copy SOP action, but in this case the use of instancing is more efficient for this particular activity.

So, let’s add another Geo to our network:

Next we’re going to replace the torus inside of this Geo with a sphere. We’re also going to add a material inside of the geo. Easy, right? I’m going to set my sphere to be pretty small ( 0.09, 0.09, 0.09 ), I’m also going to make sure that I connect my sphere to a Null (in case I want to make any other changes), and then turn on the Null’s display and render flags. Finally I’m going to add a constant Material. When we’re all said and done you should have something like this:

Excellent. Now we we back out of this nested Geo we should see just a single sphere. What?! Well, now we can set the Geo to instance – my favorite part.

Let’s start by taking a look at the parameters of our Geo. Specifically, we want to look at the Instance page. Here we first need to turn on Instancing. Next we’re going to tell our Geo to look at the CHOP called sopto1. Finally we’ll set the TX, TY, and TZ parameters to correspond to the channels called tx, ty, and tz. If this seems like crazy talk, that’s okay – check out the picture below and it should make more sense:

We also want to head to Render Page of the Geo, and set this geo to use the material ./constant1 (this means, use the material inside of this geo called constant1 – ./ is a directory pointer indicating where to look for the thing in question, in this case a constant).

Alright, now we can finally see some of our handy work – you should now see a sphere instanced at each of the vertices of the grid that we’re transforming with noise.

Now let’s kick it up a notch. Now we’re going to add another Geo to our network.

We’re going to treat this Geo slightly differently. Inside let’s add an In SOP and a Phong Material. On our SOP In let’s make sure that the display and render flags are turned on, and for your SOP choose a nice dark color – I’m choosing a deep crimson.

The In SOP allows us to pass in the geometry that we’ve already made, acting as a kind of short-cut for us. When we go back to our Geo we just need to make sure that we’ve set our Render material to be ./phong1 – like with our constant this is the pathway to and the name of the material we want to use.

Alright, now you should have a network that looks something like this:

Now we’re ready to move out of our Geo and get ready to render our scene. Zooming out of our Geo we should see a network that looks something like this:

In order to render our scene we need to revisit what we talked about at the beginning of the post – we need to add a Camera, a Light, and a Render TOP. Let’s go ahead and add these to our network.

What gives?! This doesn’t look right at all. Well, part of what’s happening is that we don’t have our camera and light positioned correctly to render the scene correctly. To make this easier to understand, let’s change up our work space so we can use the geometry viewer (one of my favorite tools). Let’s start by dividing the workspace into two windows. We can do this by using the split work space icon in the menu bar:

I like the vertical split, but you can choose whatever arrangement works for you. When you initially click on this split you’ll see two views of your current network location:

In order to see the geometry viewer we need to change the pane type selection for one of our windows. Clicking on the small drop down triangle will reveal a menu of network views. Let’s select Geometry Viewer from the list.

You should now see your network on one side, and the geometry from our Geo comp on the other side.

Now we’re cooking with gas. Alright, let’s make our lives just a little easier and change the scale of our light and camera to make them easier to see. Click on your light COMP, if your parameters window has disappeared you can bring it back by pressing “p” on your keyboard.” In the scale parameter, let’s turn that up to 10, 10, 10.

Great, now we can see part of the reason that our scene isn’t rendering the way we want it to. Our light is currently set up as a point light that’s positioned at the edge of our geometry. Let’s make some changes to our light’s properties so we get something closer to what we want. Let’s start by changing the location of our light, I’m going to place mine at 0, 10, 0.

Now let’s take a look at the Light page of the parameter’s window. Here I’m going to change my light to a Cone, and alter the cone size, delta, and rolloff. Experiment with different settings here to find something that you like.

Before you get too much experimenting done, however, you’ll probably notice that the cone of our light isn’t pointing towards the surface of our geometry. We can fix this by heading back to the Xform page of the parameters window, and setting the rotation values to -90, 0, 0.

With our light starting to take shape, let’s get our camera in order. Over at our camera, let’s make the same initial change we made to the light and turn the scale up to 10, 10, 10 – this is going to make it much easier for us to find our camera.

With the scale turned up we can see that our camera needs to be translated back, up and rotated downwards so it’s looking at the geometry. After a little bit of adjusting I think I like my camera at:

TX 0
TY 6.2
TZ 18.9
RX -16.8
RY 0
RZ 0

Boom! Alright, let’s close our geometry viewer and take a closer look at our Render TOP to see what we’ve made.

Nice work. This is a good looking start, and now that you know how it’s made you can start to really have fun – camera placement, light placement, noise amplitude, you name it, go crazy, make something fun or weird, or just silly.

Shuffling Words Around | Isadora

About a month ago I was playing about in Isadora and discovered the Text/ure actor. Unlike some of the other text display actors, this one hides a secret. This actor lets you copy and paste into a whole block of text that you can then display one line at a time. Why do that? Well, that’s a fine question, and at the time I didn’t have a good reason to use this technique, but it seemed interesting and I tucked it into the back of my mind. Fast forward a few months, and today on the Facebook group – Isadora User Group (London) – I see the following call for help:

And that’s when I remembered the secret power of our friend the Text/ure actor. Taking Raphael’s case as an example let’s look at how we might solve this problem in Izzy.

First off we need to start by formatting our list of words. For the sake of simplicity I’m going to use a list of 10 words instead of 100 – the method is the same for any size list, but 10 will be easier for us to work with in this example. Start off by firing up your favorite plain text editing program. I’m going to use TextWrangler as my tool of choice on a Mac, if you’re on a PC I’d suggest looking into Notepad++.

In TextWrangler I’m going to make a quick list of words, making sure that there is a carriage return between each one – in other words I want each word to live on its own line. So far my sample text looks like this:

Boring, I know, but we’re still just getting started.
Next I’m going to open up Isadora and create a new patch. To my programming space I’m going to add the Text/ure actor:

So far this looks like any other actor with inlets on the left, and outputs on the right. If we look closely, however, we’ll see a parameter called “line” that should catch our attention. Now for the magic. If we double click on the actor in the blue space to the right of our inlets, we suddenly get a pop up window where we can edit text.

Next let’s copy and past our words into this pop up window. Once all of your text has been added, click “OK.”

Great. Now we have our text loaded into the Text/ure actor, but we can’t see anything yet. Before we move on, let’s connect this actor to a projector and turn on a preview so we can get a sense of what’s happening. To do this start by adding a Projector actor, then connecting the video outlet of the Text/ure actor to the video inlet of the Projector.

Next show stages – you can do this from the menu bar, or you can use the keyboard shortcut Command G. If you’re already connected to another display then your image should show up on your other display device. If you’d like to only see a preview window you can force preview with the keyboard shortcut Command-Shift F.

Alright, now we’re getting somewhere. If we want to change what text is showing up we change the line number on the Text/ure actor.

Alright. So now to the question of shuffling through these different words. In Raphael’s original post, he was looking to not only be able to select different words, but also to have a shuffling method (and I’m going to assume that he doesn’t want to repeat). To crack this nut we’re going to use the shuffle actor, and some logic.

Let’s start by adding a shuffle actor to our patch, and let’s take a moment to look at how it works.

Our Shuffling actor has a few parameters that are going to be especially important for us – min, max, shuffle, and next. Min, like the label says is the lowest value in the shuffle stack; Max is the highest value. Shuffle will reset the our counter, and reshuffle our stack. The next trigger will give us the next number in the stack. On the outlet side of our actor we see Remaining and Value. Value, is the shuffled number that we’re working with; Remaining is how many numbers are left. If we think of this as a deck of cards then we can start to imagine what’s happening here. On the left, shuffle is like actually shuffling the deck. Next is the same as dealing the next card. On the right the Value would be the face value of the card dealt, while remaining is how many cards are left in the deck.

Alright already, why is this important?! Well, it’s important because once we get to the end of our shuffled stack we can’t deal any more cards until we re-shuffle the deck. We can avoid this problem by adding a comparator actor to our patch. The comparator is a logical operation that compares two values, and then tells you when the result is a match (True) and when it doesn’t (False).

To get our logic working the way we want let’s start by connecting the Shuffle’s Remaining value to the value2 of the Comparator. Next we’ll connect the true trigger from the Comparator back to the Shuffle inlet on the Shuffle actor.

Great, now we’ve made a small feedback loop that automatically reshuffles our deck when we have used all of the values in our range. Now we can connect the Value outlet of the Shuffle Actor to the Line input of the Text/ure actor:

There we have it. Now the logic of our shuffle and comparator will allow us to keep running through our list of words that are in turn sent to our projector.

OSC Remote Control | TouchDesigner

There’s a lot to love about the internet, really. But I think one of my favorite things is how it connects people, how it flattens old hierarchies (not really, but let me wax idealistic for the sake of this intro) and connects people. In starting to program with TouchDesigner, I did the thing that any smart n00b would do – I joined the forum. The TouchDesigner forum is a great place to ask questions, find answers, learn from some of the best, and to offer help. We’ve all been stuck on a problem, and a commons like this one is a great place to ask questions, and keep tabs on what others are doing. To that end I shared a technique for sending and receiving OSC data with TouchDesigner back in October of 2013. I also shared this on the forum, because this happened to be something that I figured that others might want to know more about. My post was a simple example, but often it’s the simple examples that help move towards complex projects. As it turns out, someone else was fighting the same battle, and had some questions about how to make some headway – specifically they wanted to look at how to create an interface that could be controlled remotely with TouchOSC or from the TouchDesigner control panel itself. Ideally, each interface’s changes would be reflected in the other – changes on a smartphone would show up in the TouchDesigner control panel, and vice versa. I caught the first part of the exchange, and then I got swallowed by the theatre. First there was The Fall of the Hose of Escher, then Before You Ruin It took over my life, and then I spent almost a month solid in Wonder Dome. Long story short, I missed responding to a question, and finally made up for my bad Karma by responding, even if belatedly. It then occurred to me that I might as well write down the process of solving this problem. If you want to see the whole exchange you can read the thread here.

Enough jibber-jabber, let’s start programming.

For the sake of our sanity, I’m going to focus on just working with two sliders and two toggle buttons. The concepts we’ll cover here can then be applied to any other kind of TouchOSC widget, but let’s start small first. One more disclaimer, this one creates a messy network. If we took a little more time we could clean it up, but for now we’re going to let it be a little bit sloppy – as much as it pains me to do so.

First things first, if you’re new to using TouchOSC you should take some time to get used to the basics and start by reading through this overview on using TouchOSC. Open Sound Control (OSC) messages are messages that are sent over a network. OSC can be used locally on a computer to allow for communication between programs, and it can also be used between multiple machines in order to allow them to communicate with one another. Interface tools like TouchOSC allow users to create custom interfaces that control some aspect of a program. That’s a very simplistic way of looking at OSC, but it’s a good start. The important takeaway here is that when we use OSC we’re actually relying on some network protocols to facilitate the communication between computers.

To get started I selected a simple interface on an iPod Touch that came with TouchOSC. Again, I wanted something with two toggles and two sliders to serve as our example. We can set-up our mobile device by starting TouchOSC and hitting the circular option / configuration button in the corner.

Once we do that we’ll see a screen with a few different options. We want to select the OSC connection tab.

From here we need to configure a few settings. First off you’ll want to set add the IP address of your computer into the “Host” field. To find your computer’s IP address you can use the ipconfig command to quickly find your IP address (if this sounds like another language, check out this youTube video to see what I’m talking about). I also want to take note of the IP address of the device – this is the “Local IP address.” I also want to take a close look at the outgoing and incoming ports, I’ll need to use these numbers in TouchDesigner to make sure that I can talk and listen to this device.

Alright, now that we know a few things about our mobile device now we can head back to TouchDesigner.

First off, let’s take a look at how to listen to the incoming data. In a new network at an OSC In CHOP.

In the parameters box let’s make sure that we’re listening to the same port that we’re broadcasting on – in my case it’s port 10000. Now you should be able to start hitting buttons and moving sliders to see some new channels appear in your CHOP. Here’s it’s important to take a closer look at the naming convention for our channels. Let’s look at 1/fader1 first. TouchOSC has a great utility for creating your layouts, and if you let it do the naming for you this is the kind of format that you’ll see. The semantics of this are page/widgetNameWidgetNumber. So by looking at 1/fader1 we can read this to mean that this is on page one, it’s a fader, and it’s number (the order it was created) is one. This naming convention is going to be important to take note of, and will save you a lot of headaches if you take some time to really wrap your head around how these widgets are named.

Before we start building an interface to control let’s take a moment to get a few more ducks in a row. I’m going to connect my OSC In CHOP to four different select CHOPS – each control is going to be routed to a button or slider, and I want to make sure that I’m only dealing with one channel to do this.

For my own sanity I’ve named each of the selects with a name that corresponds to what channel they’re carrying. You can choose any naming convention that you’d like, but definitely choose a naming convention. This kind of patching can get messy quickly, and a solid method for naming your operators will server you well.

Before we move on let’s take a closer look at one of the selects to see how we can pull out a particular channel.

You’ll notice that in the Channel Names I’ve used the name *fader1 rather than 1/fader1. What gives?! Either of those names is going to give me the same result in this case. I’ve elected to use the asterisk modifier to save myself some time and because I’m only using page one of this particular interface. What does the asterisk modifier do? I’m so glad you asked – this particular modifier will give results that match anything after the asterisk. If, for example, I had 1/fader1, 2/fader1, and 3/toggle1 as incoming channels, the asterisk would pull out the 1/fader1 and 2/fader1 channels. Naming and patterning isn’t important for this particular example, but it’s a technique to keep your back pocket for a rainy day.

Okay, now that we’ve got our OSC In data ready, let’s build a quick interface. In this instance I’m going to use two vertical sliders from the TUIK presets in the pallet browser. You can find them here:

I’m also going to add two Button COMPs and a Container COMP to my network.

Before we move forward, I need to make a few quick changes to by buttons. You’ll notice that the sliders both have CHOP inlets on their left-hand side, but my buttons do not. This means that my sliders are all ready set-up to receive a channel stream to change them. My buttons aren’t ready yet, so let’s take a look at the changes we need to make. Let’s start by diving into our button.

If this is your first time taking a look inside of button comp take a moment to read through a quick overview about working with buttons in TouchDesigner. We’re going to want to add a CHOP In to this component, and we’re going to also want the changes from the Touch interface to drive how our button’s color changes. Here’s what that’s going to look like:

Here I’ve added an In CHOP that feeds to a Math CHOP that I’ve renamed to “i” that’s finally connected to our Out CHOP. So why a Math, and why rename it? If you look closely at the Text TOP you’ll see that it’s driven by several expressions allowing it to change color based on its active state – this is part of what’s happening in the expression CHOP originally called “i”. Here our Math CHOP is set to add our in and the “ii” CHOP (formerly just “i”) together. By changing the name of the operators, I’ve avoided re-writing the scripts to save myself some time.

With our buttons and sliders finally ready we can start connecting our interface elements. There are lots of ways to build interface elements in TouchDesigner, but today I’m just going to use the ability to wire components vertically to do this. First I’m going to layout my buttons and sliders in an approximate location that matches my TouchOSC layout just to help me get organized initially. Next I’m going to connect them through their vertical inlets to my container COMP. In the end, if you’re following along, it should look something like this:

Finally, you’ll want to take some time to adjust the placement of your buttons and sliders, as well as adjusting their color or other elements of their appearance. My final set up looks like this:

If you’re still with me, this is where the real magic starts to happen. First up we’re going to connect the our corresponding OSC In values to our control panel elements that we want to control. Fader 1 to fader 1, toggle 1 to toggle 1 and so on. Next we’re going to connect all four of our control panel elements to a single Merge CHOP.

Next we’ll need to do a little renaming. To make things easier I’m going to use a Rename CHOP and a Constant CHOP. Here our Constant CHOP holds all of the names that we want to apply to the channels that are coming into our Rename CHOP. Here’s where all of that funny business about naming our channels becomes important. To make sure that I’m feeding back data to TouchOSC in a way that properly associates changes to my sliders I need to follow the naming conventions exactly the way they’re coming into TouchDesigner. 1/fader1 that’s since become v1 needs to have it’s name changed back to 1/fader1. You can see what I mean by taking a closer look at the network below:

Last but not least we’re going to connect our rename CHOP to an OSC Out CHOP. When we set out our OSC out we need to know the IP address of the device that we want to communicate with, and we need to know the port that we’re broadcasting to. I also like to change my OSC Out to be samples, and to turn off “Send every cook.” Sending with every cook is going to create a lot more network traffic, and while it’s not an issue for TouchOSC, if you’re working with someone using MaxMSP having this trick up your sleeve is going to make them much happier. Here’s what our OSC Out operator should look like:

Whew! Alright gang, at this point you should be ready to start making the magic happen. If you’ve got everything set-up correctly you should now be able to drive your control panel in TouchDesigner either from the panel we created, or from a TouchOSC setup. As a bonus (why we did all of this hard work) you should also be able to see your changes in either environment reflected in the other.

Inside Wonder Dome | TouchDesigner

In approaching some of the many challenges of Wonder Dome one of the most pressing and intimidating was how to approach programming media playback for a show with a constant media presence. One of the challenges we had embraced as a team for this project was using Derivative’s TouchDesigner as our primary programming environment for show-control. TouchDesigner, like most programming environments, has very few limitations in terms of what you can make and do, but it also requires that you know what it is that you want to make and to do. Another challenge was the fact that while our team was full of bright and talented designers, I was the person with the broadest TouchDesigner experience. One of the hard conversations that Dan and I had during a planning meeting centered around our choices of programming environments and approaches for Wonder Dome. I told Dan that I was concerned that I would end up building an interface / patch that no one else knew how to use, fix, or program. This is one of the central challenges of a media designer – how to do you make sure that you’re building something that can be used / operated by another person. I wish there were an easy answer to this question, but sadly this is one situation that doesn’t have simple answers. The solution we came to was for me to do the programming and development – start to finish. For a larger implementation I think we could have developed an approach that would have divided some of the workload, but for this project there just wasn’t enough time for me to both teach the other designers how to use / program in TouchDesigner and to do the programming needed to ensure that we could run the show. Dan pointed out in his thesis paper on this project that our timeline shook out to just 26 days from when we started building the content of the show until we opened.

The question that follows, then, is – how did we do it? How did we manage to pull of this herculean feat in less than a month, what did we learn along the way, and what was an approach that, at the end of the process, gave us results that we used?

Organization

Make a plan and stay organized. I really can’t emphasize this enough. Wonder Dome’s process lived and died in our organization as a team, and as individuals. One of the many hurdles that I approached was what our cuing system needed to be, and how it was going to relate to the script. With three people working on media, our cue sheet was a bit of a disaster at times. This meant that in our first days working together we weren’t always on the same page in terms of what cue corresponded to what moment in the play. We also knew that we were going to run into times when we needed to cut cues, re-arrange them, or re order them. For a 90 minute show with 20 media cues this is a hassle, but not an impossibility. Our 25 minute long kids show had, at the beginning, over 90 media cues.

In beginning to think about how to face this task I needed an approach that could be flexible, and responsive – fast fast fast. The solution that I approached here was to think about using a replicator to build a large portion of the interface. Replicators can be a little intimidating to use, but they are easily one of the most powerful tools that you can use in TouchDesigner. Here the principle is that you set up a model operator that you’d like subsequent copies to look like / behave like. You then use a table to drive the copies that you make – one copy operator per row in the table. If you change the table, you’ve changed / remade your operators. In the same way if you change your template operator – this is called your “Master Operator” – then you change all of the operators at once. For those reasons alone it’s easy to see how truly powerful this component is, but it’s also means that a change in your table might render your control panel suddenly un-usable.

Getting started here I began by first formatting my cue sheet in a way that made the most sense for TouchDesigner. This is a great time to practice your Excel skills and to use whatever spreadsheet application / service that you prefer to do as much formatting as possible for you. In my case I used the following as my header rows:

Cue Number – what was the number / name for the cue. Specifically this is what the stage manager was calling for over headset. This is also the same name / number for the cue that was in the media designer script. When anyone on the team was talking about M35 I wanted to make sure that we were all talking about the same thing.
Button Type – Different cues sometimes need different kinds of buttons. Rather than going through each button and making changes during tech, I wanted to be able to update the master cue sheet for the replicator, and for the properties specified to show up in the button. Do I want a momentary button, a toggle, a toggle down, etc. These things mattered, and by putting these details in the master table It was one less adjustment that I needed to make by hand.
Puppet – Wonder Dome had several different types of cues. Two classifications came to make a huge difference for us during the tech process. Puppet entrances / exits, and puppet movements. Ultimately, we started to treat puppet entrances and exits as a different classification of cue (rather than letters and numbers we just called for “Leo On” and “Leo Off”, this simplified the process of using digital puppets in a huge way for us), but we still had puppet movements that were cued in TouchDesigner. During the tech process we quickly found out that being able to differentiate between what cues were puppet movements and what cues were not was very important to us. By adding this column I could make sure that these buttons were a different color – and therefore differentiated from other types of cues.

Here I also took a programming precaution. I knew that invariably I was going to want to make changes to the table, but might not want those changes to be implemented immediately – like in the middle of a run for example. To solve this problem I used a simple copy script to make sure that I could copy the changed table to an active table when we were in a position to make changes to the show. By the end of the process I was probably fast enough to make changes on the fly and for them to be correctly formatted, but at the beginning of the process I wasn’t sure this was going to be the case. The last thing I wanted to do was to break the show control system, and then need 25 minutes to trouble shoot the misplacement of a 1 or 0. At the end of the day, this just made me feel better, and even if we didn’t need it in place I felt better knowing that I wasn’t going to break anything if I was thinking on my feet.

replicator in action

Above you can see a replicator in action – looking at an example like this I think helps to communicate just how useful this approach was. Method, like organization, is just a way to ensure that you’re working in a way that’s meaningful and thoughtful. I’m sure there are other methods that would have given us the same results, or even better results, but this approach helped me find a way to think about being able to quickly implement cue sheet changes into our show control environment. It also mean that we standardized our control system. With all of the buttons based on the same Master Operator it gave the interface a clean and purposed look – staring down the barrel of a 25 show run, I wanted something that I didn’t might looking at.

Thinking more broadly when it comes to organization, beyond just the use of replicators for making buttons I also took the approach that the show should be modular and organized as possible. This meant using base and container components to hold various parts of the show. Communication to lighting and sound each had their own module, as did our puppets. For the sake of performance I also ended up placing each of the locations in their own base as well. This had the added bonus of allowing for some scripting to turn cooking on and off for environments that we were using or not using at any given point in the show. We had a beast of a media server, but system resources were still important to manage to ensure smooth performance.

If you want to learn more about replicators you can read through this post about getting started using them.

Show Control

Show control, however, is about more than just programming buttons. Driving Wonder Dome meant that we needed a few additional features at our fingertips during the show. Our show control system had two preview screens – one for the whole composite, and one for puppets only. One of the interesting features of working in a dome is how limited your vision becomes. The immersive quality of the projection swallows observers, which is downright awesome. This also means that it’s difficult to see where all of the media is at any given point. This is one of the reasons that we needed a solid preview monitor – just to be able to see the whole composition in one place. We also needed to be able to see the puppets separately at times – partially to locate them in space, but also to be able to understand what they looked like before being deformed and mapped onto the curved surface of the dome.

The central panel of our control system had our cues, our puppet actions, our preview monitors, and a performance monitor. During the show there were a number of moments when we had a dome transformation that was happening while nearly simultaneously a puppet was entering or exiting. While originally I was trying to drive all of this with a single mouse, I quickly abandoned that idea. Instead I created a simple TouchOSC interface to use on an iPad with another hand. This allowed me to take a double handed approach to diving the media added some challenge, but paid itself back ten fold with a bit of practice. This additional control panel also allowed me to drive the glitch effects that were a part of the show. Finally it also made for an easy place to reset many of the parameters of various scenes. In the change over between shows many elements needed to be reset, and but assigning a button on my second interface for this task I was able to move through the restore process much faster.

If you’d like to learn more about using TouchOSC with TouchDesigner there a few pages that you might take a glance at here:

TouchOSC | Serious Show Control
Sending and Receiving OSC Values
Visualizing OSC Data

Cues

Beyond creating a system for interacting with TouchDesigner, a big question for me was how to actually think about the process of triggering changes within my network. Like so many things, this seems self evident on the face of it – this button with do that thing. But when you start to address the question of “how” then the process becomes a little more complicated. Given the unstable nature of our cue sheet, I knew that I needed a name-based approach that I called from a central location. Similar to my module based approach for building the master cue sheet, I used the same idea when building a master reference sheet.

With a little push and guidance from the fabulous Mary Franck, I used an evaluate DAT to report out the state of all of the buttons from the control panel, and name them in a way that allowed for easy calling – specifically I made sure that each cue maintained it’s name letter and number convention from our cue sheet.

On the face of this it seems like that’s an awful lot of scripts to write – it is, but like all things there are easier and harder ways to solve any problem. My approach to here was to let google spreadsheets do some work for me. Since cue sheet was already set-up as a spread sheet, writing some simple formulas to do the formatting for me was a quick and easy way to tackle this. It also meant that with a little bit of planning my tables for TouchDesigner were formatted quickly and easily.

It was also here that I settled on using a series of Execute DATs to drive the cooking states of the various modules to control our playback performance. I think these DATs were some of the hardest for me to wrap my head around – partially because this involved a lot of considered monitoring of our system’s overall performance, and the decisions and stacking necessary to ensure that we were seeing smooth video as frequently as possible. While this certainly felt like a headache, by the time the show was running we rarely dropped below 28 frames per second.

If you want to read a little more about some of the DAT work that went into Wonder Dome you can start here:

Evaluate DAT Magic
These are the DATs You’ve Been Looking For

Communication

All of the designers on the Wonder Dome team had wrestled with the challenges of communication between departments when it comes to making magic happen in the theatre. To this end, Adam, Steve, and I set out from the beginning to make sure that we had a system for lights, media, and sound to all be able to talk with one another without any headache. What kind’s of data did we need to share? To create as seamless a world as possible we wanted any data that might be relevant for another department to be easily accessible. This looked like different things for each of us, but talking about it from the beginning ensured that we built networks and modules that could easily communicate.

In talking with lighting, one of our thoughts was about passing information relative to the color of the environment that we found ourselves in at any given point. To achieve this I cropped the render to a representative area, then took the average of the pixel values in that area, then converted the texture data to channel data and streamed lighting the RGBA values over OSC. We also made a simple crossfader in our stream for the times when we wanted the lighting in the scene to be different from the average of the render.

WD_Adam This technique was hardly revolutionary, but it did create very powerful transitions in the show and allowed media to drive lighting for the general washes that filled the space. This had the added benefit of offloading some programming responsibility from lighting. While I had done a lot of work in the past to coordinate with sound, I hadn’t done much work coordinating with lights. In fact, this particular solution was one that we came up with one afternoon while we were asking questions like “what if…” about various parts of the show. We knew this was possible, but we didn’t expect to solve this problem so quickly and for it to be so immediately powerful. Through the end of the run we continued to consistently get positive audience response with this technique. Part of the reason this solution was so important was be cause Adam was busy building a control system that ultimately allowed him to control two moving lights with two wacom tablets – keeping the washing lighting driven by media kept both of his hands free to operate the moving lights.

Screenshot_032314_115026_AM

The approach to working with sound was, of course, very different from working with lights. Knowing that we wanted to use spatialized sound for this show Stephen Christensen built an incredible Max patch that allowed him to place sound anywhere he wanted in the dome. Part of our conversation from the beginning was making sure that media could send location data bout puppets or assets – we wanted the voice of the puppeteers to always be able to follow the movement of the puppets across the dome. This meant that created an OSC stream for sound that carried the location of the puppets, as well as any other go or value changes for moments where sound and media needed to be paired together.

Communicating with sound wasn’t just a one way street though. Every day the Wonder Dome had a 90 minute block of free time when festival visitors were allowed to explore the dome and interact with some of the technology outside of the framework of the show. One of the components that we built for this was a 3D environment that responded to sound, animating the color and distribution of objects based on the highs, mids, and lows from the music that was being played. Here sound did the high, mid, low processing on its end, and then passed me a stream of OSC messages. to get a smoother feel from the data I used a Lag CHOP before using this to drive any parameters in my network.

Components and Reuse

Perhaps the most important lesson to be learned from this project was the importance of developing solid reusable components. This, again, isn’t anything revolutionary but it is worth remembering whenever working on a new project. The components that you build to use and reuse can make or break your efficiency and the speed of your workflow. One example of this would be a tool that we created to make placing content on the dome. Our simple tool for moving images and video around the dome would be used time and again throughout the project, and if I hadn’t take the time early on to create something that I intended to reuse, I would have instead spent a lot of time re-inventing the wheel every time we needed to solve that problem.

In addition to using this placement tool for various pieces of media in the show, this is also how we placed the puppets. During the development phase of this tool I thought we might want to be able to drive the placement of content from a iPad or another computer during tech. To make this easier, I made sure that there was a mechanism embedded in the tool to allow for easy control from multiple inputs. This meant that when we finally decided to adapt this tool for use with the puppets, we already had a method for changing their location during the show. There are, of course, limits to how much anyone can plan ahead on any project but I would argue that taking the time to really think about what a component needs to be do before developing it makes good sense. I also made use of local variables when working with components in order to make it easier to enable or disable various pieces of the tool.

You can read more about some of this process here:

3D Solutions for a 2D World
Container Display

Documentation and Comments

comment example I nearly forgot to mention one of the most critical parts of this process. Documentation and commenting. If I hadn’t commented my networks I would have been lost time after time. One of the most important practices to develop and to continue is good commenting. Whenever I was working on something that I couldn’t understand immediately by just looking at it, I added a comment. I know that some programmers use the ability to insert comments with individual operators, but I haven’t had as much success with that method. Personally, I find that inserting a text DAT is the best way for me to comment. I typically write in a text editor using manual carriage returns. I also make sure that I date my comments, so if I make a change I can leave the initial comments and then append the comment with new information. I can’t say enough about the importance of commenting – especially if you’re working with another programmer. Several times during the process I would help lighting solve a problem, and good commenting helped ensure that I could communicate important details about what was happening in the network to the other programmer.

I think it’s also important to consider how you document your work. This blog often functions as my method of documentation. If I learning something that I want to hold onto, or something that I think will be useful to other programmers then I write it down. It doesn’t do me any good to solve the same problem over and over again – writing down your thoughts and process help you organize your approach. There have been several times when I find shortcuts or new efficiency in a process only when I’m writing about it – the act of taking it all a apart to see how the pieces connect make you question what you did the first time and if there’s a better way. At times it can certainly feel tedious, but I’ve also been served time and again by the ability to return to what I’ve written down.

TouchDesigner | Container Display

A quick one today that addresses problems I didn’t know that I had until I decided that I wanted to show off. In Wonder Dome I’m finding that sometimes the best way to build a scene is to use methods encapsulated inside of a container that make some change to some source imagery. This approach gives me a quick access to the parameters that I’m the most likely to use in a given method, without requiring that I always dive into the container to make changes. For example, I’ve build a handy tool for moving video assets around in the dome. This is fantastic, but if I drop this container into another container that needs its own set of buttons I quickly end up with a mess. Here’s an example of what I’m talking about:

Looking at this container from the root folder I can the control panels for this network, and for it’s child. There are lots of ways to address this. I might, for example, just dive into the container find the child container and turn off its display parameter.

That’s a fine approach if I’m only working with a couple of different scenes, but what happens when I suddenly have 10 or 20 scenes in a given network, each with a number of containers with control panels inside of them? Then I have a headache on my hands as I have to methodically go through and carefully disable each of the containers that I don’t want displayed.

We can solve this problem by using a python expression to conjure some TouchDesigner black magic. I’m going to solve this problem by asking my encapsulated containers to look at their parent operator and to complete a simple logical operation. When I’m ready to lock down a scene in my network, I add a capital “P” to the name of the container – for me this means it’s “P”erformance ready.

Now, instead of toggling that display parameter on my encapsulated container instead I’m going to use this expression:

0 if me.parent().name[0] == “P” else 1

“What on earth does this mean?!”
We can call for the name of our parent with the following expression:

me.parent().name

Better yet, we can ask for a specific character in from that name. If we ask for the character in the 0 position (remember that in programming languages 0 is often the first number in a list), we get the first letter from the name of our parent operator. Putting these two ideas together we get the expression:

me.parent().name[0]

Alright, now that’t we have the fist character from our parent operator’s name, let’s do a simple logical operation. Using an if else statement we can set one of two values. In this case I’m toggling between the values 0 or 1 (off or on). The syntax of this starts with the value if your logical operation is true, and then specifies what value to use if that statement is false. With this in mind, the whole expression is: