Pencil tool sometimes truncates lines making them too short
GIMP version: 2.8.18
Operating System: macOS High Sierra 10.13.6 (17G65)
Package: I think it is installed from http://gimp.lisanet.de/
Description of the bug
When I draw straight lines, the lines are sometimes too short.
Reproduction
Is the bug reproducible? Always, for a particular line length.
Reproduction steps:
- Select pencil tool, set to Pixel brush (1), size 20
- Click to draw a square.
- Shift-command drag to make a horizontal line.
- Move cursor until legend at bottom of screen says "20.0 pixels. Click to draw the line."
- Click to draw line.
Expected result:
The line should be 20 pixels long. The line should end where the dotted cursor was.
Actual result:
The line is 19 pixels long. The last column of pixels wasn't drawn.
Additional information
In the screen shot, I draw lines of various different lengths. First line: should be 20 pixels long, really 19. Second line: should be 21, really 19. Third, should be 22, really 21. Fourth, should be 23, really 21. Fifth, should be 48, really 48. Last, should be 50, really 48. There's no obvious pattern for which lengths work and which don't. It appears to be repeatable for any particular length. Starting position doesn't seem to matter.
A strange thing is after getting a truncated line, if I then draw a connected perpendicular line with shift-command-click, the missing pixels at the end get filled in and the perpendicular is drawn from where the line should have been. So it's not a problem of the mouse moving as I click causing the line to end in the wrong spot. Somehow gimp "knows" where the line ended, just doesn't draw it to that point.