Handle newly encountered cases in BDF files.

[MattHeffron]

Better handling of a glyph with ENCODING of -1. (From Monaco-10.bdf converted mac font)
I treat it as the slug glyph, instead of the default of a solid block.
This addresses issue: #2014
None of my test cases had that any glyph with that ENCODING.

This same bdf file also caused corrupted bitmap glyphs due to glyphs with zero width bitmap and zero advance (escapement). This has been corrected in a separate commit.

[pamoroso]

On Linux Mint 22.1 Cinnamon I tested the changes up to edcc0e3 and now BDF:WRITE-BDF-TO-DISPLAYFONT-FILES processes the Commodore 64 font with no errors.

But how can I determine the name of the converted font to feed to the TEdit charlooks menu? I added the directory with the new font to DISPLAYFONTDIRECTORIES but entering c64, c64d, c6416, c6416-mrr, or anything else in the Other field of TEdit's charlooks menu yields Can't find OTHER font c6416-mrr.

[MattHeffron]

But how can I determine the name of the converted font to feed to the TEdit charlooks menu? I added the directory with the new font to DISPLAYFONTDIRECTORIES but entering c64, c64d, c6416, c6416-mrr, or anything else in the Other field of TEdit's charlooks menu yields Can't find OTHER font c6416-mrr.

This appears to be due to the way that font files are named.
Since there is no punctuation between the FAMILY and the SIZE in the file name (e.g. C6416 when FAMILY = C64 and SIZE = 16), calls to FONTSAVAILABLE will fail to report the font. (Internally, it does everything in UPPERCASE.)
It does find the file, then it takes apart that filename and checks that the pieces match the original FAMILY, SIZE, etc. original arguments. It takes the first character that is a digit as the beginning of the size. So, for c6416 it splits it to FAMILY = C and SIZE = 6416. The FAMILY doesn't match the C64 it was expecting, so it rejects the match.

Interestingly, calling (FONTCREATE 'C64 16) works correctly.
And, after creating that, FONTSAVAILABLE does succeed, as does using "Other" in TEDIT.

So, what should BDF:WRITE-BDF-TO-DISPLAYFONT-FILES do if the FAMILY argument provided, or internally determined FAMILY, contain any digits?

[nbriggs]

I don’t think it should do anything different, but the documentation should say “don’t name fonts with names that end in digits”

[MattHeffron]

“don’t name fonts with names that end in digits”

Actually the font FAMILY should not contain any digits, it's not just at the end.
Documented in latest commit, which includes some other ease of use changes.

[pamoroso]

I actually pass to BDF:READ-BDF c64d.bdf which doesn't end in digits but the function picks the name in the font metadata which does:

STARTFONT 2.1
FONT c64
SIZE 16 75 75
FONTBOUNDINGBOX 16 16 0 -4
STARTPROPERTIES 3
FONT_DESCENT 4
FONT_ASCENT 12 
DEFAULT_CHAR 0 
ENDPROPERTIES
CHARS 95
STARTCHAR C0032
ENCODING 32
SWIDTH 666 0
DWIDTH 16 0
BBX 16 16 0 -4
BITMAP
0000
...

Anyway I'd say READ-BDF works pretty well:

[MattHeffron]

I actually pass to BDF:READ-BDF c64d.bdf which doesn't end in digits but the function picks the name in the font metadata which does

It isn't the name of the file in the call to BDF:READ-BDF that matters, it is in BDF:WRITE-BDF-TO-DISPLAYFONT-FILES that the FAMILY argument provided, or internally determined from the metadata, that shouldn't contain digits (not just end with digits).

So, if you had entered
(PROG1 T (SETQ C64D (BDF:READ-BDF "c64d.bdf" T))) ; Using the VERBOSE parameter
it would have displayed:

Name: c64
Family: c64
Size: 16
Weight: MEDIUM
Slant: REGULAR
Expansion: REGULAR

(Wrapping with the (PROG1 T ...) prevents the printing of the BDF::BDF-FONT structure returned and enables seeing that display.)

If then you called
(BDF:WRITE-BDF-TO-DISPLAYFONT-FILES C64D "{DSK}my-font-path>" :FAMILY "Commodore")
it would have returned five values:

{COMMODORE16-MRR/743,121356}
(0 33 34 35 225 226 227 236 238 239 253)
NIL
NIL
NIL

(The 743,121356 is the address of the IL:FONTDESCRIPTOR object, and would be different every time.)
This would have written files named like: {DSK}my-font-path>c0>Commodore16-MRR-C0.DISPLAYFONT and it would have been findable in the TEdit Char Looks menu Other with the name "Commodore".

[pamoroso]

I updated to b3796eb and regenerated the font as you explained. Now TEdit detects the font with no issues.

[pamoroso]

Looks good to me.