PDA

View Full Version : Flocking Heading



rcallicotte
05-16-2012, 09:52 PM
I searched and found nothing about this. As you can see by the images, when I begin the Flock at Frame 0, the horse and rider face one direction (toward the Director), but as soon as I move the director even one frame, the Flock changes 180 degrees.

How do I control the direction of my instances in a Flock?

Lewis
05-17-2012, 12:31 AM
Hmm yes it happened to me also recently and i can't remember how how i solved it. Hmm you might wanna wait for James to show up. Maybe you could for now start complete flocking below frame 0 (like -10 or so).

EDIT: Does your mesh (model) facing z+ axis in modeler ? If is rotated other way (regardless how you rotated it in layout) that might be problem here.

jameswillmott
05-17-2012, 01:05 AM
Send the scene to Fogbugz please!!! Agents shouldn't suddenly snap round.

rcallicotte
05-17-2012, 05:54 AM
Where is Fogbugz?

Here is the scene without the LWOs.


Send the scene to Fogbugz please!!! Agents shouldn't suddenly snap round.

rcallicotte
05-17-2012, 06:00 AM
In Layout, my Mesh(es) face(s) Z-.

In Modeler, Z-.


Hmm yes it happened to me also recently and i can't remember how how i solved it. Hmm you might wanna wait for James to show up. Maybe you could for now start complete flocking below frame 0 (like -10 or so).

EDIT: Does your mesh (model) facing z+ axis in modeler ? If is rotated other way (regardless how you rotated it in layout) that might be problem here.

Lewis
05-17-2012, 06:09 AM
Try to rotate mesh in modeler to Z+ axis and save it, then check scene in layout.

rcallicotte
05-17-2012, 06:39 AM
Lewis, I will this afternoon. I can't access it right now. Thanks!

If anyone wants to check it out, I attached it above without the mesh.


Try to rotate mesh in modeler to Z+ axis and save it, then check scene in layout.

RebelHill
05-17-2012, 06:44 AM
Where is Fogbugz?

send it to [email protected]

rcallicotte
05-17-2012, 07:44 AM
Thank you.



send it to [email protected]

rcallicotte
05-22-2012, 06:36 AM
Got this from LW-bugs --

I don't think it's a bug per se, what is happening is the direction is derived from the velocity using the current system.

At frame 0 the velocity is 0 and the agents default to facing along +Z, as soon as the simulation moves to frame 1 there is a tiny acceleration along -Z and the new rotation switches 180 degrees.

To 'fix' this would involve a rewrite, or alternatively start rendering from frame 1 and ignore the shift on frame 0, or rotate the scene so the goal directors are in front of the flock from frame 0.

Future behaviours for flocking agents are planned to have a dampening effect on the rotation so your agents would turn slowly and not snap, but that is out of scope for any bug fix release.

Afalk
05-22-2012, 07:32 AM
Got this from LW-bugs --

I don't think it's a bug per se, what is happening is the direction is derived from the velocity using the current system.

At frame 0 the velocity is 0 and the agents default to facing along +Z, as soon as the simulation moves to frame 1 there is a tiny acceleration along -Z and the new rotation switches 180 degrees.

To 'fix' this would involve a rewrite, or alternatively start rendering from frame 1 and ignore the shift on frame 0, or rotate the scene so the goal directors are in front of the flock from frame 0.

Future behaviours for flocking agents are planned to have a dampening effect on the rotation so your agents would turn slowly and not snap, but that is out of scope for any bug fix release.

Why not just start the sim at frame -5, typically that's easy enough to pull off in a scene from my exp. :D

rcallicotte
05-22-2012, 08:12 AM
Setting my object correctly in Modeler to Z+ fixed it for me.