Bug report: Xterm problems with Greek pi (π) and box-drawing
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I submitted the following to the Debian bug tracker #931305.
While using proportional fonts, the Greek letter pi (π) is treated as a box-drawing character or, more likely, as missing from the proportional font altogether. This happens only at certain point sizes AND/OR only with specific fonts.
Scenario 1: Greek pi works, but box-drawing does not
With these settings:
xterm.vt100.faceName: DejaVu Sans Mono
xterm.vt100.faceSize: 10
XTerm.vt100.forceBoxChars: false
The greek letter pi is displayed correctly, but the second vertical line (drawn with U+2502) is almost the same as the first one (drawn with U+007C).
Scenario 2: Greek pi does not work, but box-drawing does
With these settings:
xterm.vt100.faceName: DejaVu Sans Mono
xterm.vt100.faceSize: 10
XTerm.vt100.forceBoxChars: true
The Greek letter pi is drawn using a fixed-size (bitmap) font. The second vertical line is properly displayed using box-drawing characters.
Scenario 3: faceSize: 9.5 forceBoxChars: false works for both
With these settings:
xterm.vt100.faceName: DejaVu Sans Mono
xterm.vt100.faceSize: 9.5
XTerm.vt100.forceBoxChars: false
Everything appears to work as intended.
Scenario 4: Fira Code works using settings from scenarios 1 and 3
With these:
xterm.vt100.faceName: Fira Code
xterm.vt100.faceSize: 10
XTerm.vt100.forceBoxChars: false
Or this changed:
xterm.vt100.faceSize: 9.5
Everything seems to work as intended.
Scenario 5: forceBoxChars always breaks Greek letter pi (π)
With these settings:
xterm.vt100.faceName: Fira Code
xterm.vt100.faceSize: 10
XTerm.vt100.forceBoxChars: true
Regardless of typeface, enabling forceBoxChars will always draw the letter pi in a bitmap font.
