3d track motion question

epirb wrote on 5/19/2004, 5:27 PM
Can somebody explain to me why this happens.....I'm sure it's doing what it's supposed to.I just need help understanding the concept/theory.
The setup:
4 video tracks with clips,
>set track 1 T/M to 3d souce alpha and lets say rotate on the y axis 60 degrees
then reduce the size so it fits into the title safe area(to make it easy)
>do the same to track 2 except set y to -60 degrees to oppose it.
so far so good ,and you can see track 3 in the backround.
>now set track 3 to 3d track alpa like tracks 1 & 2. and posistion it by rotating it upwards, say by just setting the x rotation to 60.

So here's my question,why doesn't the backround show track 4?
it's just black. keep in mind I have left track 4's track motion to its default source alpha setting.
I can either turn on track 4's T/M , but then it intersects the other three top layers.
I know if I set tracks 2&3 to become child tracks of 1 then the image appears the way I want it.
so why does it work that way? help splain to me Lucy !?
Maybe if I can wrap my head around this I will answer my next question regarding keyframing the upper tracks.

Comments

Cheno wrote on 5/19/2004, 6:30 PM
This is strange.. not sure the reasoning behind it... however if you add a blank track as a parent above 1, 2 and 3 and then child them to it, leave 4 alone.. you'll be fine.

Mike
epirb wrote on 5/20/2004, 5:46 AM
Thanks Mike ,
I'll give that a try, but I'm still kinda wondering why when you get to 4 tracks the fourth is black, I wanna keyframe the other three tracks individualy.