I’ve always liked programs that feel a little alive, even on a machine like the ZX81. For Heart Beat, as usual, I was inspired by others. I ran across this EKG Heart program by Holger Palmroth for the Spectrum and decided to adapt and expand it for the ZX81.
I thought I’d try something a bit different this month. I’d been looking at different ways to build maps for years but never really did much with them. After watching a video on binary partitioning, I decided to see if I could build a simple map builder on the ZX81. This is the result.
I wrote this back in August and I’m finally getting around to publishing it. It was first shared in my BASIC group, but the ZX81 lacks a lot of the functionality needed for it to run well. Undeterred, I hacked at the program to not only display the twisted cylinder, but also add a bit of randomness to the demo.
As plans go, I actually have a few programs teed up to share. Many are smaller programs that I could work on here and there. Occasionally, I run across an idea that upends those plans and I end up going another direction. So, here we are in September with a math program for the Collatz Conjecture.
In my final article about Mandelbrot sets, I’m sharing the hybrid program built from the last two. After finishing the chunky graphics version, I envisioned a merged version. This split graphic version is a nice compromise to showcase the beauty of the fractal.
At the one level, you can sum up most programs into three big groups: business, gaming, or educational. Most of my programs fit into one of these base categories. The standouts are generally the animation or demo programs that really have no distinct genre. Even those, however, I can lump into one of the big three without much effort. There are times when these categories get blurred and a program can fit into two or more categories. This month’s program is one of those.
I’ve been a bit busy this month so I choose a relatively short program in order to not miss my self imposed deadline. To that end, I present to you April’s belated graphic program: Sphere. This program will easily run on a 2K ZX81. With some trimming, if you are so inclined, it will probably run in the original 1K of RAM as well. Although I doubt too many people with a ZX81 have less than 16K of RAM. Take a look at the listing to get a feel for how small this program really is.
I ran across some interesting Iterative Imaging Code that creates interesting fractal like graphics using POV-Ray. Basically, it creates the image and then uses that image to create the next one.
I was looking over my Lorenz Attractor images and wondered how the spiral would look close-up. So, I created another version looking down on the spiral with the tendrils coming up from the it. To make it stand out from the others, I changed the sphere colors to blue and added some filtered transparency to them. It makes them look a bit like beads of glass.
I was searching for some pov-ray liquid routines and ran into an interesting article on The Lorenz Attractor In 3D. The Lorenz Attractor is an interesting equation and surprisingly beautiful. Since there was a sample pov-ray macro on the site, I thought it would be fun to generate some pictures. I don't have much yet, but I think these look pretty cool. In some ways, these look like galaxies colliding. What do you think?