▼The Racket Drawing Toolkit
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find-family-default-font-id
find-or-create-font-id
get-face-name
get-family
get-font-id
get-post-script-name
get-screen-name
set-post-script-name
set-screen-name
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font-name-directory<%> : interface?
There is one font-name-directory<%> object: the-font-name-directory. It implements a mapping from font specifications (face, family, style, and weight) to information for rendering text on a specific device. Programmers rarely need to directly invoke methods of the-font-name-directory. It is used automatically when drawing text to a dc<%> object. Nevertheless, the-font-name-directory is available so that programmers can query or modify the mapping manually. A programmer may also need to understand how the face-and-family mapping works.

To extract mapping information from the-font-name-directory, first obtain a font ID, which is an index based on a family and optional face string. Font IDs are returned by find-or-create-font-id and get-font-id . A Font ID can be combined with a weight and style to obtain a specific mapping value via get-screen-name or get-post-script-name.

For a family without a face string, the corresponding font ID has a useful built-in mapping for every platform and device. For a family with a face string, the-font-name-directory interprets the string (in a platform-specific way) to generate a mapping for “screen” drawing (to a canvas’s dc<%>, a bitmap-dc%, or a printer-dc%). When drawing to a post-script-dc% object, the face-specific mapping defaults to the family’s mapping.

(send a-font-name-directory find-family-default-font-id family)
 → exact-integer?
  family : 
(one-of/c 'default 'decorative 'roman 'script
          'swiss 'modern 'symbol 'system)
Gets the font ID representing the default font for a family. See font% for information about font families.

(send a-font-name-directory find-or-create-font-id name 
  family) 
 → exact-integer?
  name : string?
  family : 
(one-of/c 'default 'decorative 'roman 'script
          'swiss 'modern 'symbol 'system)
Gets the face name for a font ID, initializing the mapping for the face name if necessary.

Font ID are useful only as mapping indices for the-font-name-directory.

(send a-font-name-directory get-face-name font-id)
 → (or/c string? false/c)
  font-id : exact-integer?
Gets the face name for a font ID. If the font ID corresponds to the default font for a particular family, #f is returned.

(send a-font-name-directory get-family font-id)
 → 
(one-of/c 'default 'decorative 'roman 'script
          'swiss 'modern 'symbol 'system)
  font-id : exact-integer?
Gets the family for a font ID. See font% for information about font families.

(send a-font-name-directory get-font-id name 
  family) 
 → exact-integer?
  name : string?
  family : 
(one-of/c 'default 'decorative 'roman 'script
          'swiss 'modern 'symbol 'system)
Gets the font ID for a face name paired with a default family. If the mapping for the given pair is not already initialized, 0 is returned. See also find-or-create-font-id.

Font ID are useful only as mapping indices for the-font-name-directory.

(send a-font-name-directory get-post-script-name font-id 
  weight 
  style) 
 → (or/c string? false/c)
  font-id : exact-integer?
  weight : (one-of/c 'normal 'bold 'light)
  style : (one-of/c 'normal 'italic 'slant)
Gets a PostScript font name for a font ID, weight, and style combination.

See font% for information about weight and style.

(send a-font-name-directory get-screen-name font-id 
  weight 
  style) 
 → (or/c string? false/c)
  font-id : exact-integer?
  weight : (one-of/c 'normal 'bold 'light)
  style : (one-of/c 'normal 'italic 'slant)
Gets a platform-dependent screen font name (used for drawing to a canvas’s dc<%>, a bitmap-dc%, or a printer-dc%) for a font ID, weight, and style combination.

See font% for information about weight and style.

(send a-font-name-directory set-post-script-name font-id 
  weight 
  style 
  name) 
 → void?
  font-id : exact-integer?
  weight : (one-of/c 'normal 'bold 'light)
  style : (one-of/c 'normal 'italic 'slant)
  name : string?
Sets a PostScript font name for a font ID, weight, and style combination. See also get-post-script-name.

See font% for information about weight and style.

(send a-font-name-directory set-screen-name font-id    
  weight    
  style    
  name) → void?
  font-id : exact-integer?
  weight : (one-of/c 'normal 'bold 'light)
  style : (one-of/c 'normal 'italic 'slant)
  name : string?
Sets a platform-dependent screen font name (used for drawing to a canvas’s dc<%>, a bitmap-dc%, or a printer-dc%) for a font ID, weight, and style combination.

See font% for information about weight and style.

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