Bug 427309

Summary: Japanese Glyphs have unreliable Cell Widths
Product: [Applications] konsole Reporter: FlyingWaffle <flyingwaffle>
Component: fontAssignee: Konsole Developer <konsole-devel>
Status: REPORTED ---    
Severity: normal CC: flyingwaffle
Priority: NOR    
Version: 20.08.1   
Target Milestone: ---   
Platform: Gentoo Packages   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description FlyingWaffle 2020-10-03 20:41:47 UTC
SUMMARY
Japanese glyphs have unreliable cell widths, causing entire lines to shift left/right with certain glyphs.  This was noticed while playing around with the unimatrix script: https://github.com/will8211/unimatrix

STEPS TO REPRODUCE
1. Get unimatrix script: https://github.com/will8211/unimatrix
2. Run it with 'unimatrix -s 80 -l k' or 'unimatrix -s 80 -l m' (higher number will have faster scrolling).
3. Watch as the glyphs scroll past, it will be noticeable that when including Japanese glyphs the lines will shift left/right as the fall past.  Comparison with other terminal emulators makes this much easier to notice.

OBSERVED RESULT
Shifting left/right of lines with certain Japanese font glyphs.

EXPECTED RESULT
Consistent spacing and width of lines that contain Japanese font glyphs.

SOFTWARE/OS VERSIONS
Operating System: Gentoo Linux
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.15.1
Kernel Version: 5.8.13-gentoo
OS Type: 64-bit
Processors: 8 × AMD Ryzen 7 PRO 3700U w/ Radeon Vega Mobile Gfx
Memory: 13.6 GiB of RAM
Graphics Processor: AMD RAVEN