Hey there..

Im taking some baby-steps into pFlow, and doing some tests.

In this one test the particles does an unwanted rotation flip, when their age is around 5-10. See the youtube link, for the animation.

And see the attached pictures for the pFlow, and where the particles flip. Is there a way to avoid this?

	Video

also is there a way to have the particles only cast shadows??

Can you upload your scene? Or some screen shots of the pflow events? Also what version of Max you’re using.

And you can make particles cast shadows only if you go into the object properties and uncheck visible to camera. Pflow is a little different because you have to go into the particle view and select either the main PF Source or a specific event, right-click and go to the properties there. Selecting the PF Source in the viewport, right-clicking and going to object properties won’t work.

3ds Max 2009 SP1, 2010 SP1
Maya 2012
Windows 7 Professional 64-bit
Dual Intel Xeon E5520, 6 GB Ram
NVIDIA GeForce GTX 460 OC

cool, thx for the hiding info:-)

Im using max 2010, and here is a picture of the pFlow;

The find target is rotating the particles because of the speed space follow. I made a work around example using a spherical gravity instead of the find target.

3ds Max 2009 SP1, 2010 SP1
Maya 2012
Windows 7 Professional 64-bit
Dual Intel Xeon E5520, 6 GB Ram
NVIDIA GeForce GTX 460 OC

	Attachment
pflow_speed_space_follow__max_2009.zip

cool:-) Ill have a go later today, with adjusting the pFLow.

Ive tried the pFlow that you suggested, and it work fine with cubes. But when you use planes thats when the flipping starts happening. See the youtube links for the two different previews. Also here are the pictures of the different pFlows:-

	Video

	Video

You’re right. I didn’t notice the cubes flipping because they flip exactly 180 degrees. What I did for a work around is to make the rotation operators unique and give the particles a 180 degree rotation. In my sample scene, they were flipping in the middle of the second event, so I split that into two events with an age test as close to the frame where they flip. If yours are flipping in between events, you wouldn’t need to do that. I still get the rare one that is flipped 180 degrees for one frame, but it shouldn’t be noticeable in your animation unless you’re looking for it.

I also used shape instance of a plane because Max 2009 doesn’t have 2D shapes in the shape operator.

3ds Max 2009 SP1, 2010 SP1
Maya 2012
Windows 7 Professional 64-bit
Dual Intel Xeon E5520, 6 GB Ram
NVIDIA GeForce GTX 460 OC

	Attachment
pflow_speed_space_follow_planes__max_2009.zip