Geom-e-Tree in Action

Here is our instructional video on YouTube. It takes 5 minutes, so arrange your schedule accordingly!
  • Learn the "moves", see how it works - first 3 minutes.
  • Learn two "tips" in the 4th minute.
  • See more "by-hand" demonstrations of Tree and Twee in the last minute.

NOTE on 4/21: the segment on Changing Number needs to be redone to reflect the change in gesture. We will replace the video ASAP.

Geom-e-Tree "101" (41 seconds)

This is a short animation of a visual experience you might have with the Geom-e-Tree app. This is a prepared, computed sequence, not produced directly by the Geom-e-Tree app. (The instructional video above shows Tree in action.)

It begins with a binary tree opening up and touring around to some special trees while forming hexagonal, isometric, and rectangular grids, then closes back up only to re-open as a ternary tree which likewise does some of the same tricks, while morphing into a pentagram, a triangle, a diamond, and other shapes! See the script below for the whole story.

Some Geom-e-Tree Themes (28 seconds)

This short shows off eight of Geom-e-Tree's twenty themes, including one "Psych-e-Delic" theme. It's just a binary tree opening up nicely, changing its theme every 45 degrees. There is a surprise at the end when the last theme goes a little wild.

Geom-e-Tree: The Senary (6-branching) Tree (26 seconds)

This is simply the six-branched tree going opening up to 359 degrees between all branches. It seems to "go around" several times. To see what's going on, pay attention to any particular yellow branch as you re-watch. The theme is Spectrum #1. Most iDevices would have no trouble doing this in Real time using the Geom-e-Tree app.

Geom-e-Tree: Magpie Breathing Muscle (29 seconds)

This explores a very odd corner of the Geom-e-Tree pattern space, using the black & white "Magpie" theme. The angles between the branches of a binary tree open up to 340, 350, even 358 degrees and the common ratio varies between 0.80 and ~1.1. These patterns can be patiently explored with iPhone 4 and iPad or iPad 2, but will bog down an iPhone 3GS and older.

Because the common ratio (reduction factor) less than 1.0, the branches of the tree get longer instead of shorter, so there is a lot of drawing time for the app as the lines criss-cross the display many times. (By comparison, "normal" tree branches get shorter, and so drawing time is less for other trees.)


While you can do these things on your iPad or iPhone, you can't make a recording of either using the Geom-e-Tree app itself. The app is an immersive experience, not a movie-maker. These animations were produced in our lab frame-by-frame on July 29, 2011, and then merged using the P2M Mac App. We obviously don't show changing themes, or fingers on the screen, etc. The number of trees per second that the Geom-e-Tree App itself can produce depends on your device and the total length and width of all the lines that it must render to draw each tree.

Script for Geom-e-Tree "101"

You wanted to know, so here is the complete script for the tour taken by the trees in Geom-e-Tree 101. Tree pauses are not noted. Gestures are not noted below because this is a scripted animation, not "finger driven". Decreasing or increasing the angle would be done by moving one finger up or down on display. Changing the common ratio is done on the device by pinching or spreading two fingers.

You can refer to our FAQ, Q6 and Q7, for more about Common Ratio and Perfect Reduction Factor Mode (PRF Mode).

  1. We started with a binary tree using the Spectrum #1 theme, open to just 1°
  2. The tree was put into perfect reduction factor mode (PRF).
  3. The tree angle was opened up to 270°
  4. The common ratio (aka reduction factor) was changed to 1.0 (PRF mode off)
  5. The angle was then reduced down to 60°
  6. The common ratio was changed to 0.5
  7. The angle was further reduced to 30°
  8. The common ratio was changed to 2.0
  9. The angle was reduced to 1°
  10. Then a Ternary tree is started at 1° in the same Spectrum #1 theme, in PRF mode.
  11. The angle was opened to 120°
  12. We cheated and turned the PRF Mode off.
  13. The angle was increased to 144°
  14. The common ratio was changed to 1.0, and then further down to 0.5
  15. The angle was lowered to 120°
  16. The common ratio was changed to 1.0, then to 0.5, then back to 1.0
  17. The angle was lowered to 90°
  18. We're almost there!
  19. The common ratio was changed to 0.5
  20. The angle was lowered to 72°
  21. The common ratio was changed to 1.0
  22. The angle was lowered to 60°
  23. The common ratio was increased to ~2.4
  24. The common ratio was lowered to 0.5
  25. The angle was lowered to 45°
  26. The common ratio was increased to 1.0
  27. The common ratio was raised to ~2.5
  28. The angle was lowered to 1°
  29. The End!
It's not intended that anyone try to reproduce this sequence manually! The animation is very robotic or mechanical looking. You'll see all this stuff eventually just by exploring the Geom-e-Tree space. Feel free to wander. -- jm

Geom-e-Tree Animation (1980)

We made a computer-animated film in 1979-80 using a Super8 (8mm) film camera.

You can see a (blurry) digital transfer of Geom-e-Tree Animation (1980) on YouTube. This first attempt doesn't show the detail that was in the original film. We will transfer a better version of the 8mm movie ASAP, and have it done professionally.

Geom-e-Tree Animation remade for YouTube

You can see a digital replica, Geom-e-Tree Animation (2011), on YouTube. These are the same trees used in the original. The binary tree does not open as fully as it could because at the time I figured 180 degrees was wide open. --jm
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