Strange ribbon emitter behavior

[Ardenian]

I played a bit around with ribbon emitters and there is a strange issue I cannot explain myself.

I use a SIN function to get the coordinates of half of a SIN period,
using the function y = SIN( 0,5*x) with x =< PI() and x >= 0

However, the emitted particles behave strange:

Why are they thinner in the middle ?
All ribbon emitters ( one per color) are attached to a bone moving the SIN function. But they are never rotated.
I thought about making them camera anchored, but apparently it crashes the WE.

 

[Hantoo]

Because the Line Stays horizontal, And they never rotated?
Why Not try to use a Circle or square instead?

 

[Ardenian]

Hm, thanks, I will try it! ( I actually just created a circle moving bone right before this post )

Though I wonder why it gets thinner.
I did some testing, making it an attachment like nyan cat, and it seems to get thinner when the unit/ the attachment changes its height.

It should not happen with a static model though.

 

[Hantoo]

Hm, thanks, I will try it! ( I actually just created a circle moving bone right before this post )

Though I wonder why it gets thinner.
I did some testing, making it an attachment like nyan cat, and it seems to get thinner when the unit/ the attachment changes its height.

It should not happen with a static model though.

See the GIF and you will understand

 

[Ardenian]

ohhh, well, that explains it. Thank you, Hayate

Couldn't I rotate the emitter to prevent this happening ?

 

[Hantoo]

ohhh, well, that explains it. Thank you, Hayate

Couldn't I rotate the emitter to prevent this happening ?

Well that i am not sue, the knowldge i have here is very limited

 

[Ardenian]

Well that i am not sue, the knowldge i have here is very limited

After the GIF you gave me it should, if ribbon emitters are emitting on a square based place, then rotating this place should retrieve what I would like to achieve.