Flash Animation & Tempo - Page 2

Here is an example:

Basic Math
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(32 Frames Per Second) * (60 Seconds) = 1920 Frames Per Minute
(1920 fpm) / (140 bpm) = 13.71 Frames Per Beat or a [Quarter Note]

// 4/4 Timing
----------------------------
(13.71 fpb) * 2 = 27.42 Frames or a [Half Note]
(13.71 fpb) * 4 = 54.85 Frames per Measure
(54.85 fpb) * 4 = 219.42 //4 Measures
(219.42 fpb) * 4 = 877.71 //16 Measures
(877.71 fpb) * 4 = 3510.85 //64 Measures

13.71 / 2 = 6.85 Frames or an [Eighth Note]
6.85 / 2 = 3.42 Frames or a [Sixteenth Note]

As you notice, at this specific Tempo & Frame Rate the calculations do not give us whole numbers. And there is no such thing as decimal place frame numbers. Since there is no such thing as frames that resolve on decimal points, we are forced to round to the closest frame number. We always divide by 2. We are trying to get 2 to be the least common denominator for all the beats. When the number doesn't divide by 2 evenly, we are then forced to round. We round up one number and down the other. So if we had: 5 / 2 = 2.5 we would give 3 to the first set and 2 to the second set. This makes it so that the calculations can never be more than 1 frames worth off. Thus the closest you can possibly get.

To get a better understanding here is a visual.

Exp. If 9 had to be divided by 4.

Top
— — — — — — — — —  ( 9 Dashes )
— — — — —|— — — —  ( Notice on this line there are 5 dashes to the left(first set) and only 4 dashes to the right ) 
— — —|— —|— —|— —  ( And so forth )
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Here's a preview of the Flash files:

The Frame lables act as markers.