The Data Looper plugin in VDMX lets you create tracks that record data (values) from a data source, and then loop that data back, publishing it to the track's data source. Recording and playback is always quantized to the chosen clock, and the plugin also has a built-in editor that allows for quick and extensive modification of the recorded data, including scaling, warping, translation, and deletion.
In this tutorial we'll be looking at how to use the Data Looper to record incoming MIDI data and loop it quantized to the VDMX clock. For more information also see the Data Looper section of the VDMX wiki.
Playback and recording is track-based: a single plugin can have multiple tracks. Each track's value is published as a data source in VDMX. You can map these data source using any of the usual means, or by ctrl-click-dragging from the track preview (or the track editor) to any UI item. All tracks in a plugin instance are quantized to the same clock, which is selected by the pop-up button in the top-right of the plugin window. This means that all recording and playback is quantized- as long as your clock is in sync with the real world, everything you record and loop will also be in sync.
In the main plugin interface choosing "View All" displays an thumbnail preview and basic controls for every track in the plugin. Each track has its own set of controls for recording and playing back data, which are visible in this view- there's a pop-up button for changing the track's mode, and a value slider which is used by many of the modes. Every track has a "mode"- this mode determines what the track is doing at any given point of time.
For making adjustments to the recorded data the track editor interface allows you to make chronological modifications to the track's data. You can switch to the editor UI by either double-clicking on a preview in "View All" or selecting a specific track from the plugin's pop-up button. The main editor area has three basic sections- there's a small strip along the bottom that can be used to change the duration of the track. This automatically quantizes edits to the nearest full measure. Along the top of the editor is another strip- this strip lets you create or reposition warp points. Warp points are temporary markers that are used to distort or rearrange the data in a track. You click in the strip to make a warp point, and if you want to reposition a warp point you just click and drag it around. Warp points can be deleted by "tearing them off" the strip. The majority of the editor is taken up by a preview of the data you recorded. if you click on a warp marker in this area and drag it, the data on either side of it will be distorted. you can also click and drag on the space between warp points to slide it around, and rearrange the track data. If you hold down option while you click and drag, you'll copy the data before moving it.