Using POPs in TouchDesigner opens the door to exciting new techniques for visual generation and manipulation. Let’s explore some examples.
The POP operator family is a goldmine for creative exploration. I discover new possibilities every day, and I am still far from mastering 3D techniques the way I would like to.
As always, the best way to learn is by doing. So, in this post I would like to share three examples of how POP operators can be used creatively. Let’s get started.
POPs in TouchDesigner: Connectivity and Proximity
The POP family comes with several interesting operators, that ease the creation of complex visual patterns.
Among all POP operators, there are four I find particularly compelling:
- Connectivity: this operator controls how points are connected within a grid
- Neighbor: it uses the P attribute to find the closest points for each point of the input, indexing the closest points in the Nebr array attribute
- Ray: this operator casts a ray from each point of the input. The direction is defined by the Ray attribute. If a set of triangles and quads are connected to the second input, the rays are tested against them
- Proximity: it connects nearby points within a near/far distance than can be specified in the operator parameters
By using a mix of these operators, we can create dynamic and evolving textures in a very simple way.
Let’s start with a Sphere and a Grid operator. The Random and Random Size Fit parameters of the Grid operator are randomized by a Noise and Trail CHOPs. We connect the Grid to a Connectivity operator and then to the first input of a Neighbor operator. The Sphere goes into a Noise and then to the second input of the Neighbor.
From here, the Neighbor feeds the first input of a Ray operator, while the Noise feeds the second input. The Ray is connected to a Proximity operator. Again, the Noise and the Proximity go into a Math Combine where we apply two operations. First, we convert the RayHitNormal attribute to P. Then, we divide the Proximity and Noise P to get a color.rgb attribute.
Finally, we create a set of three Cache operators, merge them with the original input and render it. Et voilà, this is the result.
Get Our 7 Core TouchDesigner Templates, FREE
We’re making our 7 core project file templates available – for free.
These templates shed light into the most useful and sometimes obtuse features of TouchDesigner.
They’re designed to be immediately applicable for the complete TouchDesigner beginner, while also providing inspiration for the advanced user.
Audio Reactive POP Workflow
Audio reactivity is a well-established technique in TouchDesigner, and there are plenty of tutorials out there. So, let’s see how to create an audio reactive soundscape with POP operators.
We start with a Box operator, copy it to create a grid and apply a few transformations to centre it on screen. Then we connect a Proximity (see above) and a Math Combine operator. Here we convert the _BoundsMaxP attribute of the Proximity operator to get the color.rgb attribute. Finally, we render the chain, apply some blur and bloom effects, composite with the original signal and it’s done.
As for the audio reactive workflow, there are countless CHOP techniques out there. I personally use my own chain, which I built by drawing inspiration from several tutorials and then refined to suit my specific needs (so full credit to those creators). I won’t go too deep into this part.
What I do with the audio reactive chain is essentially use the low, mid, and high frequencies to drive some of the POP operator parameters in real time, as shown in the image.
By combining the power of POP operators with the dynamic audio-reactive CHOP chain, we can create effective, glitchy visuals in a surprisingly simple way.
POPs for Data Visualization
Data visualization is something I am truly passionate about. It turns complex information into clear, intuitive visuals, helping us better understand the world around us. We can use POPs to create data visualizations in a very simple and effective way. Let’s see how.
The Point File In POP is an operator that basically loads 3D point data from a single file or a sequence of files. While its primary use is for loading 3D models, we can use it to directly load 3D data for further manipulation.
For this purpose, we will use a dataset about air pollution in Italy and store three parameters as x, y and z data in a csv file.
Let’s load the file and apply some math for normalizing data. Then we use these data to feed a particle system, apply some transformation and render it. Et voilà, a simple but effective data visualization in just few operators.
Wrap Up
POPs are revolutionizing the way we work with point data in TouchDesigner. Thanks to their flexible and modular structure, they open entirely new possibilities for visual generation. The ways to get the most out of them are countless. As usual, the sky is the limit.
