@JP_Roy i missed that one (the last one) and now it starts to make sense. how do you usually handle the fact that probalby led 1-200 is one visual part, 201 to 400 a second one and so on ? is there a best practice ? actually i wanted to handle them directly so. part one do this part two do that and so on.
It’s for a object programmer a bit hard to change the brain thinking to one single thing 
but i will be able to do that.
Hi @carole_Tschan , 1st let me say that I am not an experienced programmer. I actually consider myself a ‘barely mediocre but enthusiastic’ programmer
I am not sure I understand the question here but I guess you are describing the LED addressing in your program vs the physical position of that LED in your build.
For example, for my cube that is physically wired up in a weird zig-zag pattern in 3 dimensions, I had to write a function that maps X0-X7, Y0-Y7, Z0-Z7 into a number from 0-511.
For the infinity mirror with 780 LEDs, I understand that he will have ‘One big rectangle containing 3 circles’ he will obviously have a very different mapping from physical LED placement to 0-779 led Addressing !
Did that help any ??
@JP_Roy sorry my wife logget into her google+ and i didn’t see it. 
so still me yeah as i thought you just map certain ranges to certain areas and then control them over the functions. Actually i have two rectangles of nearly the same size (outside and inside the mirror) once for some light and once for the effect. I will mount the mirror to the what comes next ( floor, walls, ?). Sorry but english isn’t obviously my main language. 
and yes id did help. So far i see multithreading is not supported by both chips.
I’m now still wondering if what i get from the ws2812 is fast enough. But we will see you could still go faster in your animation? I saw a delay of 20ms in your code… That doesn’t seem to be much delay
Hi @Severin_N , that posted code is my very first attempt at adapting code from someone else and I only added the 20 ms to slow down the animation that was going too fast for nice viewing.
I since modified that sketch a lot and instead of adding delays, I make more precise calculations that results in much smoother movements while also slowing down the animation.
With a very minimal sketch, I can update the 512 LEDs in my cube about 500 times per second !! With more complex calculations there is less time for so many LED updates but in your case, I really think it should be plenty !!!
@JP_Roy thanks very much that whole conversation and your patient was exactly what i was looking for when i came up with my question. i now have a much better feeling about this. i have the feeling that i’m ready to crawl… which i wasn’t until now