I just found a really nice gestures application for Linux called easystroke. I found it mentioned together with Kupfer in a Youtube comment and it lit up; Abracadabra!
This is how you can trigger any Kupfer command with mouse gestures from easystroke, without any integration "applied". Maybe in the future, we can develop a true easystrokes plug-in for Kupfer, to make this really easy.
Create the command you want to tie to a gesture. Here we make sure we have text selected somewhere and search for Selected Text, action Search With and indirect object Google. Then you press Ctrl+Return to turn this command into an object as shown below.
Save this object into a file by using the Save As... action. Choose a good name for it, and press Return. Kupfer will give you the command-as-file selected. We now press Ctrl+C to copy the path of this file to the clipboard, and we are done in Kupfer.
Now open Easystroke, add a new (global) action. Choose type "Command" and paste in the full path to the Kupfer .kfcom file in the "Details" field. Then configure a gesture (Choose a big G for Google) and you're done! As long as kupfer is running, performing the gesture should make easystroke run the command file, and make kupfer carry out the command.
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