kevinkennedy / tree

Tempest in a Tree

I like to do interactive projects and the holidays are a great excuse. Holidays also make for a firm deadline - which I need. A few years ago I did a project using Kinect for Windows to control lights and wanted to do something again this year. After seeing this video by Bob at "I Like To Make Stuff" it was clear I needed to make Tempest in a Tree.

Hardware

Hardware is pretty straightforward. A Particle Photon controls everything. The LEDs are standard WS2811 strips. The rotary encoder is some random one I found at Amazon. And the buttons are arcade buttons.

The Photon and controls are all mounted in a control box I built. I don't really have plans for it - just made it on the fly. There is a piano hinge on the back and a lock on the front. I can't say it's secure at all - just to keep people from unintentionally opening it up. The cover is acrylic I bent into shape with a heat gun. The hope is to reduce the amount of rain that gets into things. Nothing here is really waterproof so I'm doing what I can. I used this technique to drill the holes for the mounting screws.

The LEDs are mounted on green chicken fence I got at the hardware store. That's held up on some mounts I built. There are cinder blocks at the base to, hopefully, keep things from falling down. Everything is pretty wind-transparent so there shouldn't be much force from nature to knock things over.

Software

The game engine is written from scratch. There is an LED animation library included that I used for a different lighting project. I also use the NeoPixel library. In order to read the rotary encoder consistently I needed to tweak the neopixel library to re-enable interrupts after shifting out each LED. Otherwise we'd miss signals from the rotary encoder spinning. The Particle OS was also causing the LEDs to glitch during updates. This isn't a big deal during development but for the final deployment I added a call to SYSTEM_MODE(MANUAL) to disable all the Particle stuff. There is probably a cleaner way to do this.

There are some unit tests that I mostly used during development to make sure I didn't have off-by-one errors in the LED stuff. It's pretty minimal.

The code is a bit of a mess - inconsistent naming conventions, inconcistent use of #define VS const, ordering of stuff, etc. Deadlines and all :-)

Cut features

Because you can't change the date of Christmas, I needed to cut some features. Maybe next year

• Score, level, and remaining life display on the control panel
• More festive idle animations that don't bug the neighbors
• A better player died animation (currently it's one I hacked in during testing that was good enough)
• Sound - This would be so much better with sound
• Highlight the lane where your shot will go. This would actually only take a few minutes to add but you just have to stop at a certain point.
• Enemies that change lanes as they descend. Again, another 20 minute feature - but stuff like this are what keeps you from making a deadline
• More play testing - it was just me and my daughters
• Use Vinyl-cut lettering for the directions. COVID took away my access to a bunch of cool tools (laser cutters, vinyl cutter, Circut, etc.) so these things needed to wait