8.4 Font Attributes

The following paragraphs describe the CLX functions used to access font attributes.



font-all-chars-exist-p font Function
        
font
A font object.

Returns true if glyphs exist for all indexes in the range returned by font-min-char and font-max-char. Returns nil if an index in the range corresponds to empty glyph.

exists-p
Type boolean.


font-ascent font Function
        
font
A font object.

Returns the vertical ascent of the font used for interline spacing. The ascent defines the nominal distance in pixels from the baseline to the bottom of the previous line of text. Some font glyphs may actually extend beyond the font ascent.

ascent
Type int16.


font-default-char font Function
        
font
A font object.

Returns the index of the glyph drawn when an invalid or empty glyph index is specified. If the default index specifies an invalid or empty glyph, an invalid or empty index has no effect.

index
Type card16.


font-descent font Function
        
font
A font object.

Returns the vertical descent of the font used for interline spacing. The descent defines the nominal distance in pixels from the baseline to the top of the next line of text. Some font glyphs may actually extend beyond the font descent.

descent
Type int16.


font-direction font Function
        
font
A font object.

Returns the nominal drawing direction for the font. The font drawing direction is only a hint that indicates whether the char-width of most font glyphs is positive (:left-to-right direction) or negative (:right-to-left direction). Note that X does not provide any direct support for vertical text.

direction
Type draw-direction.


font-display font Function
        
font
A font object.

Returns the display object associated with the specified font.

display
Type display.


font-equal font-1 font-2 Function
        
font-1, font-2
The font objects.

Returns true if the two arguments refer to the same server resource and nil if they do not.



font-id font Function
        
font
A font object.

Returns the unique resource ID assigned to the specified font.

id
Type resource-id.


font-max-byte1 font Function
        
font
A font object.

Returns zero if the font uses linear index encoding. Otherwise, if the font uses matrix index encoding, a value between 1 and 255 is returned that specifies the maximum value for the most significant byte of font indexes.

max-byte1
Type card8.


font-max-byte2 font Function
        
font
A font object.

Returns zero if the font uses linear index encoding. Otherwise, if the font uses matrix index encoding, a value between 1 and 255 is returned that specifies the maximum value for the least significant byte of font indexes.

max-byte2
Type card8.


font-max-char font Function
        
font
A font object.

Returns the maximum valid value used for linear encoded indexes. This function is not meaningful for fonts that use matrix index encoding.

index
Type card16.


font-min-byte1 font Function
        
font
A font object.

Returns zero if the font uses linear index encoding. Otherwise, if the font uses matrix index encoding, a value between 1 and 255 is returned that specifies the minimum value for the most significant byte of font indexes.

min-byte1
Type card8.


font-min-byte2 font Function
        
font
A font object.

Returns zero if the font uses linear index encoding. Otherwise, if the font uses matrix index encoding, a value between 1 and 255 is returned that specifies the minimum value for the least significant byte of font indexes.

min-byte2
Type card8.


font-min-char font Function
        
font
A font object.

Returns the minimum valid value used for linear encoded indexes. This function is not meaningful for fonts that use matrix index encoding.

index
Type card16.


font-name font Function
        
font
A font object.

Returns the name of the font, or nil if font is a pseudo-font.

name
Type string or null.


font-p font Function
        

Returns true if the argument is a font object and nil otherwise.

font-p
Type boolean.


font-plist font Function
        
font
A font object.

Returns and (with setf) sets the property list for the specified font. This function provides a hook where extensions can add data.

plist
Type list.


font-properties font Function
        
font
A font object.

Returns the list of font properties recorded by the X server. The returned list is a property list of keyword/value pairs. The set of possible font property keywords is implementation-dependent.

properties
Type list.


font-property font name Function
        
font
A font object.
name
A font property keyword.

Returns the value of the font property specified by the name keyword. The property value, if it exists, is returned as an uninterpreted 32-bit integer.

property
Type int32 or null.


max-char-ascent font Function
        
font
A font object.

Returns the maximum char-ascent value for all characters in font.

ascent
Type int16.


max-char-attributes font Function
        
font
A font object.

Returns the maximum char-attributes value for all characters in font.

attributes
Type int16.


max-char-descent font Function
        
font
A font object.

Returns the maximum char-descent value for all characters in font.

descent
Type int16.


max-char-left-bearing font Function
        
font
A font object.

Returns the maximum char-left-bearing value for all characters in font.

left-bearing
Type int16.


max-char-right-bearing font Function
        
font
A font object.

Returns the maximum char-right-bearing value for all characters in font.

right-bearing
Type int16.


max-char-width font Function
        
font
A font object.

Returns the maximum char-width value for all characters in font.

width
Type int16.


min-char-ascent font Function
        
font
A font object.

Returns the minimum char-ascent for all characters in font.

ascent
Type int16.


min-char-attributes font Function
        
font
A font object.

Returns the minimum char-attributes for all characters in font.

attributes
Type int16.


min-char-descent font Function
        
font
A font object.

Returns the minimum char-descent for all characters in font.

descent
Type int16.


min-char-left-bearing font Function
        
font
A font object.

Returns the minimum char-left-bearing for all characters in font.

left-bearing
Type int16.


min-char-right-bearing font Function
        
font
A font object.

Returns the minimum char-right-bearing for all characters in font.

right-bearing
Type int16.


min-char-width font Function
        
font
A font object.

Returns the minimum char-width for all characters in font.

width
Type int16.