Pencil tool draws strangely jagged lines at 45°
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
If I draw a 45° line, it is jagged and uneven. (See black line in screenshot.) I expect pixel-level jaggies (like the green line), but I get 2-pixel jaggies. In addition, the line is uneven, with some 1-pixel jaggies, so it's not a simple explanation of being drawn at half-resolution or something.
Reproduction
Is the bug reproducible? Always
Reproduction steps:
- Select pencil tool, set to Pixel brush (1), size 20
- Click canvas to draw a square.
- Shift-command-click to draw a 45° line.
Expected result:
Should draw a line with smooth border, i.e. pixel-resolution stairstep.
Actual result: Line is both jagged and uneven, with a mixture of 2-pixel and 1-pixel steps.
Additional information
In the screenshot, the black line was drawn with the pencil tool. Note the nasty edges. The green line was retouched manually to show the expected line quality.
Clicking "smooth stroke" makes no difference. I don't have any weird pencil options like "angle" selected that might make lines strange (see tool screenshot).