3.4 Null TOPs and Select TOPs
In contrast to expensive TOPs, like the Blur TOP, some TOPs are 'free', and should be used generously! Two specific examples are Null TOPs and Select TOPs. These two Operators, although they don't alter any pixel, are incredibly helpful in creating more efficient workflows.
The difference between an illegible network, with wires overlapping and sprawled everywhere, and an easily followable Network are some properly placed Null TOPs and Select TOPs. Open examples 'Null_1.toe' and 'Null_2.toe'. The first file is a mish-mash of TOPs which are composited together. In this file, there is little regard for the layout of the Network, and the wires are overlapped by other Operators and other wires, making it difficult to trace any particular series of Operators. In 'Null_2.toe' a column of Null TOPs are laid out to gather all the signals before they are composited. This column of Null TOPs can serve as a checkpoint, and even at quick glance, makes it much easier to follow series of operations.
The same case can be made for Select TOPs. When working with nested Networks, using the Out TOP and pulling connections between containers can lead to the same situation as above, where Networks become illegible rather quickly. The Select TOPs can quickly and neatly reference other TOPs. Open example 'Select_1.toe'. This examples demonstrates how using In TOPs and Out TOPs can lead to extra clutter. This example is only replicating the movie 12 times! What would happen if there needed to be 100 of them? This is where the Select TOP comes in handy.
Open example 'Select_2.toe'. This example exponentially increases the amount of replicated components while being simultaneously more legible. Even more interesting is the dynamic selection system created using the Select TOPs. This is much more efficient than the manual method from before, and allows a Python script in the Select TOP's 'Select' parameter to automatically reference the corresponding replicated TOPs from the Network above, based on the digits in their names. To take this concept one step further, a Select DAT is used to drive a Replicator COMP that creates a new Select TOP, and automatically wires it to the Composite TOP every time a new item is added with the first Replicator COMP. Don't worry if this example seems daunting, Replicators and Scripting will be covered in later examples. For now, the important thing to note is that by using Select TOPs and very simple scripting, this component is relatively future-proof and won't require much maintenance. When it comes time to replicate more items, it's as easy as adding a row to a table.