Getting rid of delay() and for loops; un-delay2 is out

[J-M-L]

here is an example

LED strip animation change

Hi, When I press my button to change my LED strips animation from 'rainbow' to 'drip', it clears the strip then plays the first of the next animation, which it's meant to do, but then it goes back to play out the rest of 'rainbow'. I've tried debugging it using the 'if (mode != 0)' in the for loops of 'rainbow' but I still can't get it to change over without it playing out the rest of rainbow. Once it has finished the rainbow animation the drip animation works without issue. I assume that ther…

(quick search in the forum, I've seen many)