Oscillation (Expression Function Reference)
The Function > Profiles > Oscillation command in the expression editor inserts the token oscil(<sf>,<ef>,<sp>,<ep>,<interp>,<sa>,<ea>,<interp>) at the insertion point in the editing pane. This token generates a complex oscillating function. Replace the dummy arguments as follows:
<sf> |
Replace with an expression for the start frame of the oscillation. The value is 0 before this frame. |
<ef> |
Replace with an expression for the end frame of the oscillation. The value is 0 after this frame. |
<sp> |
Replace with an expression for the starting half-period (half-wavelength) of the oscillation in frames. |
<ep> |
Replace with an expression for the first half-period of the final oscillation in frames. |
<interp> |
Replace with LinearInterp for a linear interpolation between <sp> and <ep>, or with SplineInterp for a spline (curved) interpolation. You can use the Function > Constant submenu to insert these strings. |
<sa> |
Replace with an expression for the starting amplitude (maximum height) of the oscillation in SOFTIMAGE units. |
<ea> |
Replace with an expression for the end amplitude (maximum height) of the oscillation in SOFTIMAGE units. |
<interp> |
Replace with LinearInterp for a linear interpolation between <sa> and <ea>, or with SplineInterp for a spline (curved) interpolation. You can use the Function > Constant submenu to insert these strings. |
Example
oscil(10,90,5,15,LinearInterp,1,20,SplineInterp)
Generates an oscillation that starts at frame 10 and ends at frame 90. The first half-period lasts 5 frames and grows linearly with the second-to-last half-period lasting 15 frames. The amplitude is initially 1 SOFTIMAGE unit and grows with a spline interpolation to 20.
SOFTIMAGE|XSI v.6.01