Task #2 - Be like Water

For Task #2, you’ll have an example of what the results might look like, but you are and should feel free to put your spin on this.

Sometimes you see a cool effect and you want to reproduce it. This is one of those times.

The effect:

This was done by the folks at Adafruit, and it’s not on a Pixelblaze.

Your task: Produce this effect

Summary: “liquid” should build up at one end of the strand… Pick a spot that is the “edge”, and when the pool of liquid builds up enough, a drop should “fall” down the strand, picking up speed, and move fast enough to skip some pixels, and hit at a spot at the end of the strand.

You could make it water, ooze, blood, liquid gold, any color. Feel free to play with viscosity and gravity, but the goal is for this to look “real” like something is dripping down the strand.

There is code to crib from, but of course it’s not PB, so you’ll have to understand HOW it works and copy the technique. Also to be clear like water: You only are doing ONE drip, not many like their code… One strand of lights, which if you turn so that pixel 0 is on top, the last pixel (or for a really long strand, maybe something reasonable) is where the drop will hit. Splashing is optional.

This is meant to be a challenge, so if you don’t get it right in one try, don’t give up. We absolutely will be discussing how this works.

Big hint: you can use @wizard 's awesome KITT tutorial/code as a base… That makes a dot move down the strand… but instead of moving uniformly back and forth, we’re going to move slowly at first, then fast(er), and then splat at the end, and then a new drop will fall.

Btw, those Icicle/Meteor string lights you can buy:


are similar but after we do this task, you’ll realize how poorly they compare.


Very cool but that is a pretty big leap from the first assignment to the second… unless I am totally missing the obvious solution here. I must sit in my pondering chair and ponder this.
At this rate we will be using a PB as a guidance computer to land on the moon before the year is out. :smiley: But challenge accepted! I should post my solution to the first now.

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Actually it’s cooler looking than the difficulty level.

My hint of using KITT as a base should help a great deal. Just take each part one step at a time. Break the problem down.

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SpaceX tickets at a discount, if you bring your own ESP32 guidance computer.

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If anyone else is looking at the arduino code from Adafruit like I am… and are wondering (like I am) what an easing function is… https://easings.net/ :slight_smile: but be careful there are rabbit holes all over this assignment :smiley:


Neat find. TIL about easing functions myself.

I spent some time weekend working on a cloud. Still uncompleted, but it’s looking good regardless.

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Ya a weather cloud is on my list. Are you going to add speakers in it for some sound?

It’s one of a pair we’re doing (my partner is helping, she likes the cloud idea), so each is going to get one of a pair of tiny usb/battery Bluetooth speakers, which connect via Bluetooth together as stereo, and they will be placed at one end of each cloud. Each cloud will be 3 foot long, with a wooden ruler inside for central support, so the inside of the cloud will be for sound reverb. Then both will get hung in a room with 2 skylights.

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