Built-in Variables and Functions
The following built-in variables are available for defining actor motion equations or custom parameters with the Script Actor tool.
| Variable | Description |
|---|---|
| frame | frame number |
| pi | the mathematical value, Pi, which is equal to the angle covered by one-half of a circle |
| tSeconds | elapsed time from beginning of sequence (frame 0) in seconds |
| beginFrame | beginning frame of the section currently being recorded |
| endFrame | end frame of the section currently being recorded |
| minFrame | first frame number at which action is defined (frame 0); also first frame of a preview |
| maxFrame | last frame number at which action is defined; also last frame of a preview |
| beginSequence | frame number of the start of the current script |
| endSequence | last frame number of the current script |
| sequenceLength | length of the current script in frames |
| tSecondsSequence | elapsed time (in seconds) from beginning of the current script |
The elapsed time tSeconds is derived as follows:
tSeconds = frames/frames per second
For example, if you set frames per second to 30, tSeconds equals 1 second at frame 30, 2 seconds at frame 60 and so on.
You set the number of frames per second in the Animation Settings dialog, which is opened by selecting Settings > General in the Animation Producer dialog.
The following built-in functions are available for defining actor motion equations or custom parameters with the Script Actor tool. These functions are identical to those in the standard C math library, except that all angular values are expected and returned in degrees rather than radians.
| Function | Description |
|---|---|
| radiansFromDegrees(d) | radians from degrees |
| degreesFromRadians(r) | degrees from radians |
| secondsFromFrame(f) | seconds from frame number |
| cos(angle) | trigonometric cosine of angle |
| acos(value) | arc cosine of value |
| sin(angle) | sine of angle |
| asin(value) | arc sine of value |
| atan(value) | arc tangent of value |
| atan2(valueY, valueX) | arc tangent of valueY/valueX |
| tan(angle) | tangent of angle |
| cosh(value) | hyperbolic cosine of value |
| sinh(value) | hyperbolic sine of value |
| tanh(value) | hyperbolic tangent of value |
| exp(value) | exponential of x |
| log(value) | natural logarithm of value |
| log10(value) | base 10 logarithm of value |
| pow(x,y) | x to y power |
| sqrt(value) | square root of value |
| fabs(value) | absolute value of |
| ceil(value) | smallest integer not less than value |
| floor(value) | largest integer not greater than value |
| fmod(x,y) | floating point remainder of x/y |
| rand() | pseudo random number |
| srand(x) | set random seed |