[RWP] Using Midi Learn, the Answer to How to Prevent Sudden Jumps of Values

[Indigo]

The first part of this is on midi learn in plugIns, so don't let that 
put you off, we'll soon have AHK scripts to find the midi learn button 
in new plugs.
Farther down you get the answer about the different midi CC assignment 
modes, which to use when assigning a control surface to either Reaper 
actions or to control effects plugIns; by midi learn.
  Soft TakeOver prevents sudden jumps, so put a checkmark on that.
These relative modes are still perplexing to me, except I know they're 
for use with endless rotary encoders.

snip:
How to use MIDI Learn
1 MIDI learning in Reaper
2 MIDI learning from Actions list (Reaper 3 content)
2.1 Relative modes
MIDI learning in Reaper
Additional discussion: http://www.cockos.com/forum/showthread.php?t=4721
First, you need to make sure your controller is enabled as a control 
device. just for reference, this is what the prefs should look like
on your vsti, look in the upper right hand corner, and you will see the 
"learn" button.
Button.jpg
it will give a drop down menu:
First.jpg
select the parameter you want to automate, in this case I'll try the 
rotator speed... then you will see this box.
First-2.jpg
Move the knob of any controller that is enabled as a control in the 
preferences, and you will get this:
First-3.jpg
Here it shows exactly what is being sent to reaper. We need to go to the 
envelopes button on the track.
Choose.jpg
Now it will bring up a list of all the available envelopes to automate.
Third.jpg
(shortcut) in the latest versions (1.7x +) there are "learn buttons" 
right in the envelopes dialog:
Learneasier.jpg
with this it is one simple step, you don't have to select it from the 
GUI if you dont want :)
You have to select the same parameter you just selected for midi learn. 
make it visible and arm it. It would be nice to have this step 
bypassed... a bit tedious, but anyway... Next you want to make sure the 
right automation mode is selected. In this case, latch automation (not 
sure why)
Autolatch.jpg
After moving the knob around during playback, or in this case recording, 
of the track --
Result-A.jpg

VOILA!

MIDI learning from Actions list (Reaper 3 content)
Midilrn.gif

If your controller uses common potentiometers as knobs, use the Absolute 
mode, and it is recommended that you turn "Soft takeover" on, to prevent 
sudden jumps. If your controller uses endless rotary encoders, use one 
of three Relative modes (you will probably have to try them out to see 
which one works best with your controller).
Relative modes
Relative 1: CC value of 127 decreases the parameter value by one, CC 
value of 0 increases the parameter value by one.
Relative 2: CC value of 63 decreases the parameter value by one, CC 
value of 65 increases the parameter value by one.
Relative 3: CC value of 65 decreases the parameter value by one, CC 
value of 0 increases the parameter value by one.

That's about it!
End snip.