I’ve been using 2.77 pre-release builds for a while, and today also tested the stable release, and have never gotten the Stroke Sculpting to fully work.
The default way to sculpt Grease Pencil strokes is to go into Edit Mode and hold E and draw with the LMB, much like D+LMB is used to draw the strokes in the first place. I can draw strokes just fine, but I cannot sculpt strokes at all.
If I hold E and drag, the stroke vertex nearest to the pointer gets selected and grab-mode gets turned on. No sculpt brush appears as intended.
But if I use the D+E pie menu for Stroke Sculpting, and click the Sculpt button to the left the brush appears just fine and I can sculpt as intended. It’s just the E+LMB hotkey that’s not working.
The shortcut, E+LMB is set in my configs, as it should be by default, but it simply doesn’t work. yet, the default D+LMB shortcut for drawing strokes is also set and works just fine.
The only other mention of this problem I’ve seen so far has been on a comment on the first Stroke Sculpting demo video. I don’t think comments can be permalinked to on Youtube; it should be the very first comment by ‘johan tri handoyo’ who replies to Aligorth that the shortcut isn’t working on 2.77 RC 1 on Ubuntu.
I am also on (X)Ubuntu 14.04, 64bit, and have used tested using builds from Thomas Schiex’ PPA, which is my main install, and the official 2.77 Linux build from Blender.org
Any help as to what I’m doing wrong will be appreciated.
At the moment, I can’t test the problem on other Linux or Windows machines very soon, so I’m looking for some confirmations and will report to the tracker afterwards: To recreate the problem, (on 2.77) simply draw any strokes with Grease Pencil, go into edit mode, and try to sculpt the strokes with E+LMB.