Category Archives: personal

Homemade ink timelapse

February 21, 2023 Cassidy Curtis Leave a comment

My dear friend Eric Rodenbeck has been experimenting with creating his own homemade inks and paints from natural materials. Some of the inks mysteriously change in texture, and even color, as they dry. After months of looking at Eric’s paintings, I was intensely curious to see how these changes would look as they were happening. So, of course, I had to shoot some timelapse footage.

The inks I used here are hibiscus + lemon (pale red), hibiscus + orange peel (magenta), carrot greens + alum (yellow), and a sprinkling of sea salt for texture. Time span: about 1 hour.

If you pay close attention, something really strange happens about 11 seconds in to the video, when I added some yellow ink: wherever the yellow mixes with the magenta, the mixture turns a deep bluish green! What is going on there?

Timelapse video of homemade inks flowing across watercolor paper. Some yellow ink flows into a puddle of magenta, and wherever the two inks touch, the mixture turns a deep bluish green color. — *Magenta + Yellow = Green?*

It turns out that hibiscus gets its color from a type of pigment called an anthocyanin, whose structure and color are pH-sensitive. In an acidic environment, it’s red, but when exposed to an alkaline it turns blue. Since the yellow ink is alkaline, it turns the red hibiscus blue on contact, which then mixes with the ink’s yellow pigment, becoming a lovely vibrant green.

Here are some more photos from the day. Hopefully this will be the first of many such experiments!

alphabet, animation, art, fun, graphics, npar, personal, video

Impossible Paint: Asemic Writing

January 15, 2023 Cassidy Curtis Leave a comment

The Genuary prompt for day 14 is “asemic”, i.e. writing without meaning, which is something I’ve always loved. I thought it might be fun to try doing that with my watercolor simulation. Reader, I was not disappointed.

When we rerun the simulation with a different random seed each time, it comes to life in a different way. It turns out the Perlin noise that drives the brush movement isn’t affected by the seed, so “what” it writes stays the same, while “how” it’s written changes. The consistency seems to deepen the illusion of intentionality, which makes me super happy.

This isn’t my first time tinkering with procedurally generated asemic writing. That was in 1996, when I was working at PDI in Sunnyvale. There was a small group of us who were curious about algorithmic art, and we formed a short-lived club (unofficially known as “Pacific Dada Images”) that was much in the spirit of Genuary: we’d set ourselves a challenge, go off to our desks to tinker, and then meet in the screening room to share the results. The video above came from the challenge: “you have one hour to generate one minute of footage, using any of the software in PDI’s toolset”. I generated the curves in PDI’s homegrown script programming language, and rendered them using a command line tool called mp2r (which Drew Olbrich had written for me to use on Brick-a-Brac).

animation, effects, fun, graphics, npar, personal, video

Genuary 2023: Impossible Paint

January 8, 2023 Cassidy Curtis Leave a comment

I love to tinker with code that makes pictures. Most of that tinkering happens in private, often because it’s for a project that’s still under wraps. But I so enjoy watching the process and progress of generative artists who post their work online, and I’ve always thought it would be fun to share my own stuff that way. So when I heard about Genuary, the pull was too strong to resist.

Here’s a snapshot of some work in progress, using a realtime watercolor simulator I’ve been writing in Unity. Some thoughts on what I’m doing here: it turns out I’m not super interested in mimicking reality. But I get really excited about the qualia of real materials, because they kick back at you in such wonderful and unexpected ways. What I seem to be after is a sort of caricature of those phenomena: I want it to give me those feelings, and if it bends the laws of physics, so much the better. Thus, Impossible Paint.

fun, graphics, personal, photos, travel

Branching sand patterns

July 20, 2022 Cassidy Curtis 2 Comments

Here in Sargí, Brazil, when it isn’t raining, we get to take a lot of long walks on the beach. One feature we noticed right away were these unusual patterns just on top of the surface: little clusters of wiggly lines made of light sand that contrasted sharply against the dark, damp, compact sand beneath. Some were small and isolated, while others formed dense networks. We wondered out loud: what were these shapes, and where did they come from? Were they the trails of some tiny worm or crustacean? Detritus tossed up from the digging of underground warrens? That was our best guess on the first day. But the shapes were so tiny— barely wider than a few grains of sand— and we never saw any evidence of whatever life we imagined was creating them.

Later in the week, the weather changed, and the shapes changed too. The lines got longer, and they seemed to favor certain directions more than others. In particular, there was a strong breeze blowing up the coast, and the lines were oriented in the direction of the wind. Also there was something vaguely familiar about the way the shapes branched out and meandered, but I couldn’t put my finger on it.