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I use Path sample- to make circle of riding particle

But i cant understand- how change speed of this particle effect!

Here a link to video of my progress

by sergrlager (280 points)
if i use
float st=spawner.LifeRatio;
Position = 1*Path_1.samplePosition(st);
I have- 1xSpeed
Position = 1*Path_1.samplePosition(wavesaw(3*st));    
Position = 1*Path_1.samplePosition(frac(3*st));
i have 3x speed
but i cant understand -how do -for example- 0.5 of speed?

1 Answer

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Best answer

You are using the spawner's liferatio, which is the liferatio of the emitter (layer), not the particle.

You could try:

Position = Path_1.samplePosition(LifeRatio);, but not in the spawner script, in an evolver script.

This will move your particles during their lifetime along the path. From that you can start experimenting and just do:

Position = Path_1.samplePosition(LifeRatio * 0.5); and it'll work correctly.

by HugoPKFX (17.7k points)
the main problem is that Life ratio is (0..1)
And when you have Position = Path_1.samplePosition(LifeRatio * 0.5);
You will have only half of path- because in 1 it will be only 0.5!
When you have Position = Path_1.samplePosition(LifeRatio * 3);
its not problem- its faster! i dont know why- you must have Life ratio max =3 in this case- but is can be (0..1)
Maybe- its mean that its max - 3 of path- and its like 1 (one point on the path)
but for >=1 Its work
if its <1 - not work! its only part of path!
Maybe- because its mean that all point of path is (0..0.5) in this case<1!
That is because of the particle's Life is 1 second by default (you can change that in the spawner's script Life = 2; for example)

LifeRatio is the particle's normalize age, when the particle spawns, it has a LifeRatio of 0, when it dies it's 1, so no matter what you plug in Life, LifeRatio will always be [0-1]

You can try Position = Path_1.samplePosition(LifeRatio); and try tweaking the Life, it should modify how fast the particle moves along the path

You could also use, spawner.age, scene.time, Age which are other helpful properties

ok. Can you write common parameters for layer
 and script in evolver- to have 0.5 of speed of it? thanks
I will try it! and make video!
Because- because i try all variants- what you say- and have no result!
Here is a quick example: https://youtu.be/oovY4HRbpI4

Does it help ?
Yes- thanks! my mistake was that i use Loop particle System from start!
Yes the loop button is tricky sometimes, I am flagging the question answered then

But if i need Loop - because i need non stop effect in my scene!
and if i use for example two of it - its loks not very good in final!
I did only like this!