Using powermate dials with PyMOL
From OS X Scientific Computing
Contents |
How to get the Powermate Dial to play nicely with PyMol
Description
First, put lines similar to those in the example below into your .pymolrc file (or however you get startup commands into pymol). Pymol lets you define some keys (the function keys, ALT-[A-Z,0-9], left, right, up, down, etc) as pythonic pymol commands, like those below. I chose 2 degree increments for rotation and 0.5 for translations because these values give a visually smooth response, but change this to suit your own taste. Type help set_key in pymol for more information.
The code below dynamically assigns functions to the four programmed keys by running python scripts in pymol to reset the key bindings. Clicking the Powermate to activate the toggle function (assigned to F5) allows you to toggle cyclically through dial functionality options, thus giving you three sets of rotations and translations.
In other words, turn the dial right or left to rotate in the plus y or minus y directions. Push down while turning right or left to get the plus and minus y translations. Click the dial (press down and release rapidly) to toggle to an analogous dial set for z, and then click again for x, and then again for y.
.pymolrc
from pymol import cmd
# Define aliases for mapping in [x,y,z] rotations and translations into a single Powermate
# dial. Toggling between the three is possible if you then assign these to special keys.
# Functions for x,y,z rotations and translations using Powermate dial
# Program F1 and F2 for Rotate Right and Rotate Left
# Program F3 and F4 for Click & Rotate Right and Click & Rotate Left
# Program F5 for Click (to toggle between dialsets)
# dialset = 2
def dialx(): \
global dialset \
dialset = 1 \
cmd.set_key ('F1', cmd.turn,('x',-2.0)) \
cmd.set_key ('F2', cmd.turn,('x',2.0)) \
cmd.set_key ('F3', cmd.move,('x',-0.5)) \
cmd.set_key ('F4', cmd.move,('x',0.5)) \
print "dialset ", dialset, " [ X ]\n" \
return dialset
def dialy(): \
global dialset \
dialset = 2 \
cmd.set_key ('F1', cmd.turn,('y',-2.0)) \
cmd.set_key ('F2', cmd.turn,('y',2.0)) \
cmd.set_key ('F3', cmd.move,('y',-0.5)) \
cmd.set_key ('F4', cmd.move,('y',0.5)) \
print "dialset ", dialset, " [ Y ]\n" \
return dialset
def dialz(): \
global dialset \
dialset = 3 \
cmd.set_key ('F1', cmd.turn,('z',-2.0)) \
cmd.set_key ('F2', cmd.turn,('z',2.0)) \
cmd.set_key ('F3', cmd.move,('z',-0.5)) \
cmd.set_key ('F4', cmd.move,('z',0.5)) \
print "dialset ", dialset, " [ Z ]\n" \
return dialset
def toggle_dial(): \
if dialset == 1 : \
print "Changing to y" \
dialy() \
elif dialset == 2 : \
print "Changing to z" \
dialz() \
elif dialset == 3 : \
print "Changing to x" \
dialx() \
else: print "Dial assignment isn't working"
cmd.set_key ('F5', toggle_dial)
# Start default dial state for rotate y (arbitrary choice)
dialy()
alias ribbonize,\
hide; show cartoon; set cartoon_fancy_helices, 1; \
hide cartoon, ( resname A or resname G or resname C or resname U or resname T ); \
show sticks, ( resname A or resname G or resname C or resname U or resname T ); \
util.rainbow; color hotpink, ( resname A or resname G or resname C or resname U or resname T )
# END COMMANDS
_ feedback pop
print "PowerMate Dial interface has been enabled"
print "Finished reading ~/.pymolrc"
Here is a link to my .pymolrc in case the above is borked.
Configuring Powermate
Install the Powermate driver and reboot the system. Open up "System Preferences" and you will find a new preference pane called "PowerMate." When you open it up, you should see something similar to what is pictured below. Use "Add Settings" to add PyMol to the pulldown list you see when you go to the "Global Settings pull-down".
"Setting" should now indicate "PyMOL" or "MacPyMOL". Go below to "User Action" and set it to "Rotate Right" if it is not already showing this. Then where it says "Computer Action", change the selection at the tip of the arrow above from "No Action" as is shown in the picture immediately below to "Send Key" as is shown in the third picture.
Now press the "Change Key" button that is circled below. This allows you to change the key from the default setting to something more useful.
After you hit the "Change Key" button, you will get a second dialog box as shown below. Where I have circled "F1", you want to put in whatever you have chosen as the key equivalent with the pymol set_key function. To do so, simply push the relevant button on your keyboard. (You don't type into this box.) Then hit the OK button.
Repeat this for "Rotate Left". I also programmed "Click and Rotate Right (Left)" to send the "F3" ("F4") function keys that I had programmed into pymol. This enables me to push down on the dial to translate the molecule. Clicking the dial (program Click to send F5) toggles between dialsets for x, y and z.
