what i came up with was to generate a test tone wav file (using wavelab but i'm sure other software such as audacity can do this) with the following parameters...
- square tone, 60hz
- length = project length
- linear fade in from -20db to 0db applied across the entire length
once i had this "tone" generated, i added the wave file to magic and created a source "ToneGenerator" for it, and muted the track...
then, i created a global parameter sourcing the "ToneGenerator" audio file, and added a scale modifier of "600" (as this was for a 10 minute long song) to convert the volume level into seconds-cool!..now i have a variable that has the same value as the song position line....so -20db = 0 seconds and 0 db = 600 seconds...
from that point, i was able to link the video start time to this global...the trick now was to ensure that the video started anytime i manually scrubbed the transport "head"...
to do that, i linked the GoTo Start to a no-source ramp modifier...when the ramp reached 1, it activated the start button...as a ramp value of 1 = 1 seconds, changing the ramp value will be like specifying a frame rate so thus controlling how precise the re-triggering needed to be...i found that 5, thus 1/5 of a second, was generally fast enough and again, this can be increased to suit your needs...
now, you can also use the global parameter to trigger events at a specific time and/or time ranges etc...
as in the screen shot example, i used an input selector to apply a HueSaturation modifier during a specific time period (413-510 seconds) via an InputSelector switch...
the switch was then linked to the global parameter and an expression was applied, if((x>413 and x<510),1,0) , so that the HueSaturation would be the selected input for that time range...
alternatively, i could have simply linked the HueSaturation's bypass to achieve the same results but just wanted to demonstrate the "switch" method to open up other types of "processing" possibilities (such and scene module switching etc.)...
anyway, i know eric has something in the works that will allow us to directly tap into the current song position time, but until that is incorporated in a future release, this, for me, is an effective alternative
hope this "trick" may be helpful...
cheers!