Grease Pencil: Secondary strokes get terminated early when drawing in Continuous Drawing mode #44259

New Issue

Joshua Leung · 2015-04-04T12:46:22+02:00

Joshua Leung commented

2015-04-04 12:46:22 +02:00

System Information
Windows 8.1, 64-bit
Tested with Logitec G400s mouse

Blender Version
Broken: After Sticky Keys commit
Worked: (optional)

There seem to be two variations of these problems :/

Version 1:
When trying to draw strokes using Grease Pencil with the "Continuous Drawing" (sketching sessions) toggle enabled, the first stroke still works as expected, but all subsequent strokes will be abruptly cut off.

That is, it seems to work normally for ~300-1000 ms, before something in the event handling internals things that the mouse-held state is no longer needed/valid, and either sends a mouse-released OR just stops sending mouse moved events. The result is that no further mouse movements get registered as needing to be added to that stroke.

Enable "Continuous Drawing" from the toolbar (below the Grease Pencil Drawing operators)
Hold DKEY, then press+hold down the LMB and start scribbling a long squiggle for several seconds.
Release DKEY and LMB together
Press+hold down the LMB again, and start slowly dragging the mouse diagonally. <-- Notice how for < 1 second initially, everything seems fine working, but then the stroke stops growing even as the mouse moves.
Release the LMB. <--- Apart from the cursor changing back to normal, the stroke does no get any longer.
Repeat steps 4 and 5, and note how the same thing happens each time. It appears that the length of the stroke that does register depends on the speed with which you move the mouse only.

Version 2:
Again, this is with "Continuous Drawing" enabled. In this case, the problem is a lot more sporadic.

Hold down DKEY. Pause ~500ms - 2 seconds (NOTE: assume that even with those users with very agile reflexes cannot activate keys very quickly)
Now, start trying to draw the stroke by holding down LMB. This is recognised as a single dot - i.e. press then instant release.
Release LMB and Release DKEY. Either simultaneously, or with a delay. It doesn't seem to affect things.
Go back to 1 and try again. Note the varying results.

EDIT: Upon further testing, this second case seems to be more predictable than I initially thought. It's merely a case of how quickly after pressing the DKEY the user starts to draw the stroke. "Almost immediately" works most of the time, but is not flawless. However, even the slightest hesitation, and it starts doing dots, or devolves into case 1. The key point probably is how long this initial pause lasts.

The problem here is that most users do not really have the agility to strike multiple keys at the kinds of intervals this requires. Also, many have gotten into the habit of doing (i.e. holding on to A continously, and often for a long gap before issuing the next keys/clicks)

**System Information** Windows 8.1, 64-bit Tested with Logitec G400s mouse **Blender Version** Broken: After Sticky Keys commit Worked: (optional) There seem to be two variations of these problems :/ **Version 1:** When trying to draw strokes using Grease Pencil with the "Continuous Drawing" (sketching sessions) toggle enabled, the first stroke still works as expected, but all subsequent strokes will be abruptly cut off. That is, it seems to work normally for ~300-1000 ms, before something in the event handling internals things that the mouse-held state is no longer needed/valid, and either sends a mouse-released OR just stops sending mouse moved events. The result is that no further mouse movements get registered as needing to be added to that stroke. 1. Enable "Continuous Drawing" from the toolbar (below the Grease Pencil Drawing operators) 2. Hold DKEY, then press+hold down the LMB and start scribbling a long squiggle for several seconds. 3. Release DKEY and LMB together 4. Press+hold down the LMB again, and start slowly dragging the mouse diagonally. <-- Notice how for < 1 second initially, everything seems fine working, but then the stroke stops growing even as the mouse moves. 5. Release the LMB. <--- Apart from the cursor changing back to normal, the stroke does no get any longer. 6. Repeat steps 4 and 5, and note how the same thing happens each time. It appears that the length of the stroke that does register depends on the speed with which you move the mouse only. **Version 2:** Again, this is with "Continuous Drawing" enabled. In this case, the problem is a lot more sporadic. 1. Hold down DKEY. Pause ~500ms - 2 seconds (NOTE: assume that even with those users with very agile reflexes cannot activate keys very quickly) 2. Now, start trying to draw the stroke by holding down LMB. This is recognised as a single dot - i.e. press then instant release. 3. Release LMB and Release DKEY. Either simultaneously, or with a delay. It doesn't seem to affect things. 4. Go back to 1 and try again. Note the varying results. EDIT: Upon further testing, this second case seems to be more predictable than I initially thought. It's merely a case of how quickly after pressing the DKEY the user starts to draw the stroke. "Almost immediately" works most of the time, but is not flawless. However, even the slightest hesitation, and it starts doing dots, or devolves into case 1. The key point probably is how long this initial pause lasts. The problem here is that most users do not really have the agility to strike multiple keys at the kinds of intervals this requires. Also, many have gotten into the habit of doing <A----------------><b--><c-><d> <A---------------> <A-----------><b> <A-----><b> (i.e. holding on to A continously, and often for a long gap before issuing the next keys/clicks)

Joshua Leung commented

2015-04-04 12:46:22 +02:00

Changed status to: 'Open'

Julian Eisel was assigned by Joshua Leung

2015-04-04 12:46:22 +02:00

Joshua Leung commented

2015-04-04 12:46:22 +02:00

Added subscriber: @JoshuaLeung

Bastien Montagne commented

2015-04-04 12:48:29 +02:00

Added subscriber: @mont29

Julian Eisel commented

2015-04-04 13:03:40 +02:00

Can confirm that here. I expected these kind of glitches, modal operations like this need to be a tiny little bit more careful in their event handling than without stickies. I tried to eliminate all the glitches I could find and I asked for testing early on (which even worked out quite well), but of course I can't test every tool in blender ;) That's also why I wanted to merge in Bcon1 if possible. Anyway, should be an easy fix, will have a look in an a bit.