Switches between network branches based on an expression or keyframe animation.
This node passes the input specified in the Select input parameter to the output. The input numbering starts at 0. You can control the parameter with an expression or animate it.
For example, you could use the expression $F - 1 to switch to the
first input at frame 1, the second input at frame 2, and so on. Use the
expression ($F >= 5) to use the first input for the first five frames,
and the second input afterward (boolean operators such as >= return
0 for false and 1 for true, so the switch will select input 0 when
the expression is false and input 1 when the expression is true).
Tip
Often, you can use a Switch in a network that could potentially have errors to bypass the failing nodes. One way to do this is to use the following expression in the Select input parameter:
if (strmatch("*Error:*", run("opinfo " + opfullpath("../" + opinput(".", 1)))), 0, 1)
With this expression, the switch will use the second input, unless
it has an error, in which case it will switch to the first input.
The expression gets the operator info string (using run
expression function to call the opinfo HScript command)
of the second input (opinput(".", 1). The inputs are zero-based,
so 1 refers to the second input). If strmatch finds
an error string, the if function returns 0 (use first
input), otherwise it returns 1 (use second input).
Parameters
| Select Input | The input number (starting at 0) to pass to the output. You can use an expression to control this or animate the parameter value. |