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Thomas Leitner
03-23-2014, 07:34 AM
Hi,
is there something Iīm missing or does Instances on flocking particles donīt align to path?
I have made a flock of birds.
Then I have assigned Instancing to it.
I use the Particles type for instancing and for Rotation Alignment "Particles".
The instances donīt align to path (they donīt rotate at all).

I have also looked into the "Sparrow_Murmuration" scene from the LW 11.5 Content, but this birds donīt align, too.

Please help.
ciao
Thomas

p.s.: I use 11.5 (64 bit) for this.

Ma3rk
03-23-2014, 01:56 PM
The Sparrows scene isn't using a path; they're just pursing a Goal Director.

In general, you'd create a Null and then add a Flock Generator to that, not the Sparrow object itself.

You might want to take a look at the Flying Probes scene instead as that uses several paths.

Thomas Leitner
03-23-2014, 02:08 PM
The Sparrows scene isn't using a path; they're just pursing a Goal Director.

In general, you'd create a Null and then add a Flock Generator to that, not the Sparrow object itself.

You might want to take a look at the Flying Probes scene instead as that uses several paths.

Hi Ma3rk,
thank you for your answer.
My problem isnīt the flocking setup. My problem is that the instanced birds donīt look in the direction of flight but all look in the same direction.
Strangely enough, it worked once, but with other settings (for the flocking particles) it does not work anymore.
And if I use a target object to look at LW crashes until rendering...

ciao
Thomas

Thomas Leitner
03-24-2014, 01:41 AM
To show my problem:
Here is a picture from the "Sparrow_Murmuration" scene from the LW 11.5 Content.

120962

I simulated the flocking and changed the visibility of the instances to solid. They all look in the same direction and donīt align to their flying direction.

ciao
Thomas

LW 11.5 (64 bit)

Thomas Leitner
03-24-2014, 02:15 AM
It seems that this is a bug.
If you calculate the flocking for the whole range of the timeline the alignment works!
If you stop the calculation of the flocking before the end of the timeline the instances donīt align right.

ciao
Thomas

BeeVee
03-24-2014, 04:38 AM
Is there a reason you are still using 11.5?

B

jameswillmott
03-24-2014, 05:45 AM
Ah yes, this was by design. The positions are calculated, then a smoothing algorithm is run over them, then rotation is calculated based on the smoothed path. This is to stop small jiggles in the motion from causing sudden jerks in the orientation. If you let the sim run all the way through as you've found it works properly. If you abort halfway through, the orientation never gets calculated. I'll make a note to change this so orientation is calculated even if you abort.

Thomas Leitner
03-24-2014, 11:12 AM
Is there a reason you are still using 11.5?

B
Hi,
yes. I'm in the middle of a job. Therefore, I would not change the version.


Ah yes, this was by design. The positions are calculated, then a smoothing algorithm is run over them, then rotation is calculated based on the smoothed path. This is to stop small jiggles in the motion from causing sudden jerks in the orientation. If you let the sim run all the way through as you've found it works properly. If you abort halfway through, the orientation never gets calculated. I'll make a note to change this so orientation is calculated even if you abort.

Thank you.

ciao
Thomas

Mr_Q
03-24-2014, 11:32 AM
This is fixed in 11.6.2.