Hi,
I've just released the first version of Fragmentarium (v0.5.6), an open source, cross-platform IDE for exploring pixel based graphics on the GPU.
It was mainly created for exploring Distance Estimated systems, such as Mandelbulbs or Kaleidoscopic IFS, but it can also be used for 2D systems.
It is inspired by Adobe's Pixel Bender, but uses pure GLSL, and is specifically created with fractals and generative systems in mind.
Features:
* Multi-tabbed IDE, with GLSL syntax highlighting
* Modular GLSL programming - include other fragments
* User widgets to manipulate parameter settings.
* Different 'mouse to GLSL' mapping schemes (2D and 3D)
* Includes raytracer for distance estimated systems
* Many examples including Mandelbulb, Mandelbox, Kaleidoscopic IFS, and Julia Quaternion (all systems found here on Fractal Forums)
Fragmentarium is supposed to make GPU programming as easy as possible. For instance, a Distance Estimated system can be formulated in a few lines:
#include "DE-Raytracer.frag"
void init() {}
float DE(vec3 pos) {
return abs(length(abs(pos)+vec3(-1.0))-1.2);
}
It is also simple to create a custom slider and bind it to a variable in the GLSL code:
uniform float Angle2; slider[-180,0,180]
The code above will create a slider in the GUI with minimum, default, and maximum values specified in the brackets.
Fragmentarium can be downloaded from:
http://syntopia.github.com/Fragmentarium/There are binaries for Windows, but for now you'll have to build it yourself for Mac and Linux. You will need a graphics card capable of running GLSL (any reasonably moderne discrete card will do).
Here is a screenshot:

There's also a gallery at Flickr:
http://www.flickr.com/groups/fragmentarium/Fragmentarium is not a mature application yet. Especially the camera handling needs some work in the next versions - camera settings are not saved as part of the parameters, no field-of-view control and you often have to compensate for clipping. For future versions I also plan arbitrary resolution renders (tile based rendering) and animations.
There are probably also many small quirks and bugs - I've had several problems with ATI drivers, which seems to be much more strict than Nvidias.
Regards,
Syntopia