Problem with Particle Rotation in PF Source

[Anonymous]

I'm having a problem rotating my particles along the axis of their line of travel.  I don't see many, but of the video tutorials on the web for rotating particles using Speed Space Follow or Speed Follow in PF Source, they always skip over how  3DSM knows what the front end of the particle (instance) is that then points toward the destination along the path it is following.  In these tutorials, it always just seems to be pointing in the right direction as soon as they choose either of the above 2 parameters.  My instanced particle is a shape like a cross between an egg and a rocket.  But when I use Speed Space Follow, the particles line up in a cockeyed way.  The front, pointy end of the "rocket" is pointing off to the side randomly.  So then I have to tweak the x,y and z axises in the rotate parameter.  This is fine until I realized that I want the particles to rotate around the axis of their path.  I can't do that because of the above issue.  If I choose to animate the rotation of either the x, y or z axis, it ends up being a cockeyed, askew rotation rather than cleanly rotating around the axis of it's trajectory.  Does any body know how to line it up so that the particles rotate around the line of their trajectory as well as lining up the particles so the front end (what I mean to be the front end, not what 3dsm picks randomly) points along the axis and leads in the particles' trajectory with Speed Space Follow???  Hope this makes sense.  Thanks a ton.

[Anonymous]

P.S  I've tried adding spin to my PF source.  Although I can get the particles to spin along the axis of their trajectory when the animation is stopped, when I try to a animate that, the numbers rise on the amount of spin but the particles do not spin.  So the animation seems to effect the project numerically only.  It doesn't translate to a spin on the particles.  I'm using Autokey for this.  I'd really appreciate if someone could help me.  Thanks.

[Anonymous · Accepted solution]

I found the way to make it work (I seem to be having this conversation with myself, lol, but I'll post this in case it helps with someone in the future).

Apparently 3DSM imports instanced objects in a different orientation than how they are modeled, but the orientation seems to be off by clean increments of 90 degrees.  I was confused because the original object I had chose for the instanced particle was clearly facing down at 90 degrees form the horizon/table line yet it showed up as a bunch of particle at many odd angles.  Not knowing that despite how it looked, they were only off by multiple of 90 degrees, I messed with the x, y and z rotation amounts to try to get the particles to face forward as they traversed on their path (speed space follow) and my numbers were not increments of 90.  But they were close.  When I started messing with those rotation parameters, it occurred to me to see if they still looked right when those numbers were at mulitples of 90.  So I rounded them to that and they looked right.  Once I did that, the y parameter became the one that allowed clean rotation around the axis of the trajectory.  So it was just a matter of knowing that the adjustments I made in x and z had to be in amounts of 90 degrees and then the y parameter lined up with the trajectory so I  could rotate the particles around it.  It wouldn't work in Speed Space, only Speed Space Follow.  This doesn't make sense to me as the trajectory of the particles is a straight line for each of them (though a spray for the whole of them, like a cone).  Nevertheless, my issue is solved.  Hope that helps someone.  Cheers.