Hey, i'm making a tutorial on particle glows and I ran into a problem that had not come up when I created this the first time.
My particles seem to be following the layer based priority rather than the Z space priority, meaning, I put some text in my project then put some particles and all of the particles are floating infront of the text even if they are behind it in z space.
I made sure its a 3D layer, it has Depth Ordered checked, its on Global 3D and none of my other groups have Layer Order checked.
Like I said, i've done this project before and this did not happen... this is just one of the many bumps I came into while recreating my OWN project. There is always a problem in motion, things just dont like to work the way you would think they should.
You probably did something to cause your group(s) to become rasterized - you can tell because the icon for the group changes from a stack of three rectangles to the same stack but with a box around it. Things that can cause rasterization (or "precomping") including changing opacity of a group, changing the blend mode, or certain filters applied to the group. Look in the Properties Inspector with the rasterized group selected - the offending parameter will have a blue led light next to it.
Freelance Producer/Editor/Motion Graphics Artist
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Author, Motion 4 from Peachpit Press http://www.applemotion.net