The Loop COP is a COP subnet container. It cooks the COP network inside it multiple times. It either feeds the loop output back into the loop input, or accumulates the results by adding the loop output images together.
The Loop COP can iterate over a single frame multiple times or iterate from the first frame to the currently cooked frame, acting more like a simulation.
Inside the Loop COP, there is a Loop Data COP which is connected to the first subnet input. The results of the previous iteration will be fed back to this node. The first iteration will use the first input’s images.
Single Frame loop mode, the
$AI local variable can be used within
the loop subnet to access the loop iteration (starting at 0 for the first
iteration). When in
From Start Frame loop mode,
$F can be used as usual.
There are some restrictions placed on the COP network within the Loop COP. The network cannot change the frame range, image resolution, or add, remove, or modify planes (an error will result if you do). The Loop Data COP should always be connected directly to the first subnet input and all COPs within the Loop subnet should use it the first input instead of the first subnet input connector. The other inputs (2-4) can be used directly.
Finally, the COP with the Render flag set is used as the loop output (as COPs allow multiple display flags to be set).
Selects the looping mode.
Loops multiple times over the same frame. This can be used to apply the same effect multiple times.
From Start Frame
Loops from the start frame of the sequence to the current frame.
When used with
Feedback loop mode, the effect of the COP
network is applied gradually over time like a simulation.
Single Frame looping, this parameter determines the
number of times to loop.