Version 3·1·0

Ephemeral is a screen saver that draws animated IFS fractals, giving an ever-changing display of complex, natural shapes. The fractals evoke the structure of many objects found in nature such as plants, crystals, fire, and clouds.

The fractals are drawn as a swarm of hundreds of thousands of dots, with each one following a unique path. The relationship between these paths brings the dots together to reveal the structure inherent in the mathematical rules that define the fractal.

Try running Ephemeral a few times to get an idea of the variety it’s capable of producing: there’s always something new to see!

This screen saver is an evolution of my Windows-only Ephemera screen saver that I first released way back in 1997.


  • macOS 10·13 High Sierra or later.


Some legacy versions of Ephemeral are still available for download, but are no longer supported. However, if your Mac is running a version of macOS older than 10·13, or if your Mac is having problems with its Metal drivers, then these versions may work for you:


Release Notes

  • Version 3·1·0 — 16th January 2023
    • Ephemeral is now built as a Universal Binary, meaning it will run natively on Apple Silicon Macs. This may result in a slight improvement in efficiency, but really shouldn’t work any differently.
    • Added a workaround to fix a problem with screen savers built using Xcode 14·2 failing to show the preview in System Preferences.
  • Version 3·0·1 — 25th September 2021
    • Fixed an issue that could potentially affect the drawing process (read/write texture access), though I’m not aware of it actually causing any problems.
    • The Ephemeral screen saver is now signed and notarized by Apple, meaning it will run without trouble on recent versions of macOS.
  • Version 3·0·0 — 3rd August 2020
    • Drawing has been improved so that when different parts of the image overlap they blend together, giving a colourful, translucent appearance.
    • Animation is even smoother with Ephemeral now running at the same rate as the screen. Previously it was limited to 30 frames per second.
    • The Metal kernel used for drawing has been rewritten for much improved efficiency.
    • Metal is now a requirement as OpenGL/OpenCL support has been removed. Ephemeral 2·0·0 and 2·3·0 are still available for older Macs.
  • Version 2·3·0 — 21st March 2020
    • Fixed a bug that had the potential to cause instability.
    • Changed the defaults to give a more mellow style: slower motion with longer trails.
  • Version 2·2·1 — 1st October 2019
    • Fixed a bug where the mini-preview was blanked out in the System Preferences when the screen saver options was opened.
    • The screen saver options are now more legible in Dark Mode.
    • A few other small fixes and improvements.
  • Version 2·2·0 — 23rd November 2018
    • Rendering will use Metal on macOS 10·13 High Sierra or later, falling back to OpenGL/OpenCL.
    • The dot size is scaled to suit the screen (Metal only). This means, for example, that the mini-preview in System Preferences will draw with smaller dots on Retina displays. And when running as a screen saver on on a large high-resolution screen it will draw with larger dots.
    • Drawing is smoother due to the animation being locked to the refresh rate of each screen.
  • Version 2·1·0 (Felix Feles) — 25th September 2016
    • Significant improvements to the rendering engine have resulted in it running about 15% faster.
    • Improved smoothness of the animation.
    • There have been a large number of improvements made to the code resulting in improved efficiency and robustness.
    • All persisted defaults are removed when the Option key is held when the “Reset to Defaults” button is pressed.
  • Version 2·0·0 — 28th August 2016
    • Greatly improved appearance: the images now fade out with a gentle blur effect. Note that if your GPU doesn’t allow Ephemeral to access the graphics system, it falls back to simpler drawing with the CPU.
    • Ephemeral now draws on all screens, instead of just the primary screen. This can be changed in the screen saver options.
    • Fully rewritten rendering engine for greater efficiency.
    • Now requires OS X 10·8 Mountain Lion or later.
  • Version 1·1·2 — 12th August 2012
    • Fixed a crash on exit problem when running on OS X 10·8 Mountain Lion.
  • Version 1·1·1 — 1st August 2011
    • Ephemeral now regenerates the OpenCL kernels each time OS X is updated. This ensures that Ephemeral picks up any updates to OpenCL, and helps to retain compatibility with new versions of OS X.
  • Version 1·1·0 — 1st May 2011
    • Added a CPU mode to allow Ephemeral to run with GPUs that don’t provide the OpenCL features required.
    • Fixed a drawing glitch (occasional frame tearing).
    • Fade in over 2 seconds on start up.
  • Version 1·0·4 — 17th January 2010
    • If your Mac doesn’t support everything required by Ephemeral you will see an orange screen with a message that describes the incompatibility.
    • If any other error occurs then you will see a red screen with a message stating the nature of the problem, along with an invitation to send an error report. This is now as easy as clicking on a “Send Error Report” link in Ephemeral’s configuration options.
  • Version 1·0·1 — 19th December 2009
    • Initial public release.