[Ferenc Nagy]

I tried to extract from the font structure whether the font is monospace or proportional.
I could do it based on descriptions of the LOGFONT structure only if the font was selected by vpiCommonDialogs::getFont. The procedure fontCreateByName does not set some bytes of the font structure. Here are the differences

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The message font is Andale Mono.
Byte      Source    FontGetByCommonDial   FontCreatedByName Difference
v- Index  Size ->                    92                  92          0
 
23                        255         y        1 special  Different 
24                          1 special          0 special  Different 
25                          2 special          0 special  Different 
26                          1 special          0 special  Different 
27                         49         1        0 special  Different 

Sorry to say, according to http://msdn.microsoft.com/en-us/library ... 22837.aspx byte 27 contains the required info.

typedef struct tagLOGFONT {
00-03 LONG lfHeight;
04-07 LONG lfWidth;
08-11 LONG lfEscapement;
12-15 LONG lfOrientation;
16-19 LONG lfWeight;
20 BYTE lfItalic;
21 BYTE lfUnderline;
22 BYTE lfStrikeOut;
23 BYTE lfCharSet;
24 BYTE lfOutPrecision;
25 BYTE lfClipPrecision;
26 BYTE lfQuality;
27 BYTE lfPitchAndFamily;
28-... TCHAR lfFaceName[LF_FACESIZE];
} LOGFONT;

Member Value Description
FamilyDecorative 80 Specifies a novelty font; for example, Old English.
FamilyScript 64 Specifies a font that is designed to look like handwriting; for example, Script and Cursive.
FamilyModern 48 Specifies a monospace font with or without serifs. Monospace fonts are usually modern; examples include Pica, Elite, and Courier New.
FamilySwiss 32 Specifies a proportional font without serifs; for example, Arial.
FamilyRoman 16 Specifies a proportional font with serifs; for example, Times New Roman.
FamilyDoNotCare 0 Specifies a generic family name, which is used when information about a font does not exist or does not matter. The default font is used.
MonoFont 8 Specifies a monospace font.
VariablePitch 2 Specifies a variable-pitch font.
FixedPitch 1 Specifies a fixed-pitch font.
DefaultPitch 0 Specifies default pitch.

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predicates
  % 2014.10.22. Is the font monospace or proportional?
    fontClass:() -> font_class procedure.
 
    fontClassAux:(unsigned8 PitchAndFamily, unsigned8 Eigth) -> font_class procedure.
 
clauses
    fontClass()=fontClassAux(PitchAndFamily,PitchAndFamily div 8) :-
         F=selectedFont,
         PitchAndFamily=binary::getIndexed_unsigned8(F,27),
         succeed().
 
    fontClassAux(0,_)=fontClassFromCreation :-
         !.
    fontClassAux(_,1)=monospace :-
         !.
    fontClassAux(_,6)=monospace :-
         !.
    fontClassAux(_,_)=proportional.
 

Here fontClassFromCreation is a fact set by a constructor

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new_by_other_font_descriptor(fo(FontName,SSName,FontClass,IsBold,IsUnderlined,IsItalic,Size)) :-
        fontClassFromCreation:=FontClass,

[Thomas Linder Puls]

The LOGFONT structure specifies a logical font, not a physical font.

The LOGFONT is a "query" for a font. Windows will attempt to find a Physical font that matches the LOGFONT.

The getFont dialog look at physical fonts that installed on the computer and creates a LOGFONT structure that contains all the properties derived from the physical font.

createFontByName just creates a LOGFONT structure with name and size.