Help me repeat this effect

Hi all. I want to make a backlight for the car and I don’t know how to create this effect. I’m trying to do it through segments, but due to the fact that my tape does not divide exactly in half, I cannot start the rainbow effect with the desired color.

Not sure what issue you’re having exactly?
How is the strip layed out on the vehicle, a “U” shape with the open end at the rear?
You state

So I’m guessing the legs of the “U” are unequal lengths? I’m also guessing the data from your MCU comes in on the longer leg?
If so, you could use a few different techniques to even things out.

  1. Create a segment that starts 10 pixels (or however many it takes to even the lengths of the sides)
    Apply the effect to that with Mirror on to get both sides the same.
  2. Create an Ledmap that skips the required pixels and apply the mirrored effect.
  3. make 2 segments that go from the start to the middle and from the middle to the end (they won’t be equal lengths) Reverse the direction of the first segment and apply the effect equally to both.

There may be other/better suggestions, but without a complete description of what your layout looks like and what equipment you’re using,it’s hard to tell.

I don’t understand the problem either. Each segment can be set to whatever length you want.
You can have different effects for each segment.
Where your strip divides has nothing to do with it. Just count the number of LEDs to get to the right start point.

Here’s a visual diagram. I need the rainbow to separate from the front in the middle and join at the back in the middle

Looks like you’ll need a combination of solutions.

Ignoring the 4 corner pinks for the moment,

  1. Make two segments that are the Right and Left pixel numbers of your diagram and don’t include the 4 pink corners. On your diagram, right would be 0 - 9 (0 - Stop 10) and Left would be be 12 - 21 (12 Stop 10)
    Apply your effect with Mirror On to each of them.
  2. Create an ledmap file to move those 4 corner elements to the end (or beginning) of your strip. Create a 3rd segment for those elements and apply the final colour you need to that segment.

When you create and apply the ledmap, you’ll actually have to renumber your Left segment (probably) as the easiest “move” will be to have the Left LEDs appear just after the Right ones. So the Left segment will now be 10 - 19 (10 Stop 10).

You could do all this in one step and just apply the ledmap 1st, but I think it’ll be a little more clear if you play with mirrored segments before you add the complexity of ledmaps.

And of course, now that I look again, you could just ledmap the whole thing so that the centre of the Right strip is the start and it continues all the way around.
Then you just make 2 segments - 1 starts at the middle Right and goes up and to middle Left and the 2nd starts at middle Left and goes down and finishes at middle Right.

Apply the effect to both segments and reverse one of them.
Probably can make mirror on the just the whole mapped strip work too.