The Ginsu tool is a visual-connection-of-realtime-components thing. Ginsu is capable of some simple delays, scale adjusting, and channel remapping.

Here's how you use Ginsu. First, bring up several instances of Ginsu. Use the "Connect" button on one to drag a line over to the other. You've now connected them. (Pressing the Connect button and *not* dragging it will show you the current connections.) You'll see that the "1" "1" buttons on the two tools have changed to "1" ">" and "<" and "1". Those buttons reflect the current "input" and "output" of each Ginsu. The "1" means "channel 1", and ">" means the output is connected to some other tool, and "<" means the input is connected to some other tool.

Now, play something on channel 1, on your midi controller. You should hear your synth playing normally - the first Ginsu tool is grabbing everything on channel 1, sending it to the second Ginsu tool, which then sends it out to channel 1. Both Ginsu's are set to do "Nothing".

Now, use the "Nothing" button on the *second* Ginsu and select "Delay". The contents of that Ginsu tool should change to show a "Quarter" button. That Ginsu tool is now a "delay line". Play something on channel 1, and it will be delayed for a quarter note (inside the second Ginsu tool) before being sent to the output.

Now, create a third instance of Ginsu, and connect the first Ginsu tool to it. The first Ginsu tool should now be connected to two other Ginsu tools - anything received by the first Ginsu tool will be sent to both of the other Ginsu tools. Now, change the third Ginsu tool from Nothing to "Delay", and set it's delay value to, say, "Sixteenth". Play something on channel 1 and you should hear two copies of whatever you play, one delayed by a quarter note, and one delayed by a sixteenth.

Now, in the first Ginsu tool, use the "Ginsu" menu button to select "Echo Input -> On". Now, it will echo everything it receives, so you'll be able to hear what you play, immediately, as well as the two delayed copies.

The "1" button menus can be used to change either the input channel (on the first Ginsu tool) or the output channel (on the other two Ginsu tools).

If you actually follow these instructions, you should now understand how Ginsu works from the outside.

Internally, Ginsu works as follows. Each item under the "Nothing" menu (currently, these items are "Delay", "Ornament", "Delay Continuous", "Scadjust", and "Filter") is implemented by a separate "proc" tool. These "proc" tools implement both the GUI part (e.g. the "Delay" value button) as well as the processing part (the realtime delay). The source code for these tools is in lib/procs.k. Use the "Delay" one as an example - it is "ptool_delay". The GUI code in these tools should be familiar to anyone who's done a KeyKit tool. What's unique about these tools is that they all have "process()" methods which Ginsu uses to process realtime messages. The process() method takes a MIDI message as input, and returns a MIDI message. It must handle individual note-on's and note-off's (i.e. it won't be getting complete notes, so processing isn't quite as convenient as it might appear, depending on what you want to do).

To add a new processing tool to the Ginsu tool, just implement a ptool_* class using ptool_delay as an example, and then add that item to the array that is initialized in proc_list() at the top of lib/procs.k. New processing tools don't have to be in lib/procs.k, you can put them in a separate file.