This is KLife, a Conway's Game of Life simulator, in a jetpack compose desktop window.

One goal was to explore Compose Desktop. A secondary goal was to test out Bazel in this compose context. That hasn't yet happened.

At present, it lets you

• lets you scale the world (min 6 pixels, max 20 pixels per "bit")
• lets you resize the window (and field)
• implements a toroidal world topology
• implements standard Conway rules
• supports a start/stop button
• supports a 'step' button for single manual stepping.
• supports editing the field by clicking on it, toggling the bit on and off, while the simulation is paused.
• Each window has its own separate world state, and it's easy to create a new window with the menu or ctrl-n.
• lets you save and load "life" files - text files with a very simple format. Here's an example with a 100x80 space, a 7dp-per-square scale, and a glider.

  ### Header Comment (ignored)
  size: 100,80
  scale: 7
  3,6
  4,6
  5,6
  5,5
  4,4
  

  • Note loading is currently broken - it loads, but doesn't properly adjust the window, which then resizes the space, which then loses some of the space.

• lets you load an image bitmap file (jpg/gif/png), doing a terrible job of interpolating a black and white on-and-off image.
  • The goal was to use pngs to store the bitmap, but I opted for a text format. Image loading remains as a neat gimick.
  • Images loaded do not use "scale" but each pixel in the image is a bit in the space. Best used with very small images, such as icons.

Known issues:

• Only tested on Mac
• Resizing has bugs which can crash the app
  • it breaks the field if you pull the mouse smaller than a certain threshold (even with the minimum size constraints in place). If you go far enough, it starts throwing exceptions around negative padding numbers, etc.
  • I probably need to do something to force minimum sizes of internal components, so the window can't go smaller, but I couldn't figure that out (yet)

Note: This is the first time I've used Compose, so it's probably terrible. I'm sure dispatching mutable state updates from a Timer is the wrong move, but it was a way to generate 'ticks' so I went for it.

Also, it's partly factored out in a way that would let me evolve this into a more general home for other simulators, but I may not take it that far, so some maybe unnecessary abstractions are present.

Also also, I really need to make it so it's not storing the whole universe in a 2d array. For this purpose a sparse array would be sufficient, and given that's how my storage format works, I ought to fix the in-memory model.