Welcome to Isadora 2.5, the Creativity Server. Isadora 2.5 introduces all-new tools and features to unlock new interactive creativity, including:

  • The all-new GLSL Shader actor allows you to integrate stunning computer-generated imagery as well as new video effects into your projects
  • Get the big picture of your project, or focus in on the little details with Scene Editor and Control Panel Zoom
  • The new graphically-enhanced Toolbox allows to you to save and recall your favorite actors
  • From Aramaic to Vietnamese, Isadora now offers full international language support, so that you can render and manipulate text in nearly any language
  • Plug-and-play compatibility with the Leap Motion sensor via our new Leap Motion actor
  • Accelerated playback of AVI movies encoded with the HAP codec under Windows
  • Isadora is now “DPI Aware” under Windows, ensuring an extra crisp UI regardless of your display scaling options.
  • Awesome New Hotlinking Feature: Now you can connect two actors by bumping them together or insert an actor into a chain by dropping it on an existing link. (We’re still fiddling a bit with the algorithm, so this feature is turned off by default. To enable it, simply choose “Enable Hotlinking” in the View menu.)
  • Hard-core coders will love the line numbers, search and replace, and syntax coloring features in the code editor offered by the Javascript and GLSL Shader actors
  • New Logo and Icons: Isadora has a new logo which you’ll see in the redesigned application and document icons as well as the “splash screen.” We like to think that “Izzy Hot Pink” is the New Black. ;-)

If you are just now coming on board with Isadora 2.5, you should take the time to read the Isadora 2.2 release notes. There are several important crucial tips that will help you get the most out of Isadora 2.5.


Isadora 2.5 implements OpenGL Shading Language with a powerful new actor, which can be used by programmers and designers alike. The GLSL Shader Actor can create more interactive, graphically rich projects than ever before, with new custom interactive video filters, control of computer-generated geometric imagery, and much more.

The new GLSL Shader Actor means you can add new effects into Isadora without the need for updates and plugins -- simply copy and paste your favorite shader code, and Isadora can compile and run it right away! You can modify the code to create your own custom inputs and outputs for real-time interactive control and feedback on HD imagery. Sharing your work and updating are as easy as posting a text file. Be on the lookout for new forum pages on the TroikaTronix website where you can find and share community contributions.

Check out this new tutorial by Isadora creator Mark Coniglio to learn how you can use the new GLSL Shader Actor yourself! Be sure to visit ShaderToy and GLSL Sandbox for fantastic examples of GLSL programs you can use, too!


Starting with Isadora 2.5, you can zoom in or out in both the Scene Editor and Control Panel. Get the big picture view on your complex project with hundreds of actors, and then zoom in to focus on the small interactions. The new zoom function helps you make the most of your workspace, no matter how large your display or project!

You can use the magnifying glass icons near the bottom right to zoom in (+) and zoom out (-). Use the centre magnifying glass button to return to 100%.

To use the mouse wheel or a two-finger drag to soom in or out, hold down the OPTION key (OS X) or the ALT key (Windows). While holding the Option key, click and drag to move the view around. While zooming, the view centres on the cursor.

Finally, you can also use keyboard shortcuts to zoom. By default, use CMD SHIFT + or - to zoom in and out using the Keyboard. This zooms the current view of the Scene Editor focused on the center point of the current view. More Zoom option items can also be found under the View menu.


The Toolbox Filters have been updated with a new graphical interface. (You will still be able to see the name of each Toolbox Filter as your mouse rolls over the new icons.)

Newly added to the Toolbox Filter in Isadora 2.5 is a new “favorites” item. Click an actor and then the “heart” button to add it to the favorites, click an already favorited actor and click the heart button to remove it.

If you’d like to remove all your favorite actors, a new “Clear Toolbox Favorites” item has been added to the File menu.


This new feature is disabled by default because we’re still toying with the algorithm to reduce the number of unintended connections. That being said, many of our beta testers loved this feature so you can enable it if you want to try it out. To do so, you need only choose “Enable Hotlinking” in the View menu.

You can adjust how the hotlinking feature works in Isadora’s Preferences dialog.

When connecting two actors, the “Connect Distance” controls how far apart those actors must be before they are hotlinked. Our suggested setting for this is 10 pixels; values greater than this tend to make unintended connections. If a hotlink is in progress, the “Disconnect Distance” specifies how far apart you must drag an actor before the hotlink is disabled.

When the “Into Existing Links” checkbox is checked, you can insert a new actor between two existing actors by placing the new actor on the link. This feature only works with a horizontal link that is wide enough to accommodate the new actor. Hotlinking is not offered for diagonal or vertical links at this time.

Finally, if the “First Input/Output Only” checkbox is checked, then only the first input or output of an actor will be considered for hotlinking. Check this box to if you are seeing too many unintended connections.


The text through Isadora is now represented by UTF-8 strings. You can now use international characters in the Text Draw, Text/ure, Text Comparator and Text Chopper actors!


Take advantage of the innovative Leap Motion Sensor on your next project with direct integration through a built-in Isadora actor! There are a massive number of sensor inputs with the new leap motion actor to facilitate fine interactive control, including:

  • number of hands
  • Left and right palm position (x/y/z)
  • swipe L->R (trig)
  • swipe R->L (trig)
  • circleL (trig)
  • circleR (trig)
  • tap (trig)
  • left/right hand angle
  • left/right hand distance

The trigger outputs are when the system recognizes a gesture (swipe L->R, etc.) The others are continuous outputs. Check out a forthcoming tutorial for a full list of parameters and new uses!


The following actors have been updated to use GPU-based processing in Isadora 2.5:

  • Gaussian Blur (now just as beautiful as the CPU version)
  • Spinner
  • Slit Scan
  • Warp
  • Auto Fade
  • Explode

Also be sure to check out the new Pulse Values actor!


Isadora now supports accelerated playback on Windows using the HAP codec, offering incredible performance gains on SSD equipped computers. You should get started by installing the free HAP for DirectShow codec created by Renderheads. Use your favorite video editing software to create HAP encoded AVI files, and then simply drop them into Isadora. (Right now we know that you can encode successfully with Adobe Premiere and also with Vegas Pro. We will post a knowledge base article listing some free/inexpensive software that will do this encoding as soon as we’ve compiled a list.)


Isadora 2.5 introduces several improvements to the Javascript and GLSL Editor Windows, including:

  • Syntax Coloring and Line Numbers
  • Indent / Unindent text using Command-] and Command-[ (Mac) or Control-] and Control-[ (Windows)
  • Auto-indent. When you hit return, the new line will have the same tab/spaces as the previous line. This can be toggle on or off with Command-Shift-A (Mac) or Control-Shift-A (Windows)