Helmuth:
nice work man, try it with the plasma @Skorn showed here: http://arduino.cc/forum/index.php/topic,151306.0.html(very easy to adapt, but you have to slow it down...)
Please, do the next video in a dark environment, than we can enjoy more of the colors.
Thanks Helmuth, for the flowers XD
I already tried some plasma effects and the fire simulation from this thread. But the distance from the LEDs to the surface of the orb is to big to have a smooth and valid animation. I also tried with one of the acrylic glass cylinders from my first lamp, but even for this the distance was to big.
For the next project I will use a bigger tube inside the cylinder and also use 8 instead of 4 or 6 columns. This will end up in a at least 8 by 8 or 8 by 10 matrix. The LEDs will be more compact on the surface of the tube they are mounted on, so I hope this will be better for such cool animations with plasma, fire etc.
@fungus: Thanks for the tip. I will give it a try on my next project. The fastest solution would be a 255 values precalculated hue table with the according RGB data, causing 765 bytes in progmem.