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Particle system start speed (startSpeed) as a curve
It appears that in a particle system you can set the starting velocity of the particle not only to a scalar value, but also to a curve. Here's what the documentation says on the matter:
When using curves, this values acts as a scale on the curve.
This isn't even proper English.
It isn't clear what this means. So, how does the curve work as a start speed of the particle system? What can be accomplished with it?
Answer by cdr9042 · Dec 03, 2019 at 02:56 AM
the horizontal axis of the curve means the time passed during a particle system's duration. For example, if you turn off looping and set the particle's duration to 5 seconds, and set the start speed curve to go from 0 to 1, then when the particle starts firing, it will gradually increase the start speed from 0 to 1 during its 5 seconds duration.
Doesn't seem to be the case in 2019.3.7f1, only the leftmost curve value is used, i.e in your example speed will just stay at 0 :(
@MaxYari It is because all your particles are generated at time 0:00 . At time 0, the leftmost value is used. If you have particles generated at time 0:01, they will use speed at time 0:01 from the curve.
@MaxYari I think you are using Bursts in Emission and all your particles spawned at time 0. If you use Rate Over Time, you will see how the curve works.
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