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{{DISPLAYTITLE:_FREEFONT}}
{{DISPLAYTITLE:_FREEFONT}}
The [[_FREEFONT]] statement frees a font handle that was created by [[_LOADFONT]].
The [[_FREEFONT]] statement frees a font handle that was created by [[_LOADFONT]].




Line 12: Line 11:
* You cannot free a font which is in use. Change the font to a QB64 default font size before freeing the handle (see example below).
* You cannot free a font which is in use. Change the font to a QB64 default font size before freeing the handle (see example below).
* Predefined '''QB64''' font handle numbers can be used before freeing a font:
* Predefined '''QB64''' font handle numbers can be used before freeing a font:
**'''_FONT 8 ''' - default font for [[SCREEN (statement)|SCREEN]] 1, 2, 7, 8 or 13
**'''_FONT 8 ''' - default font for [[SCREEN]] 1, 2, 7, 8 or 13
**'''_FONT 14''' - default font for [[SCREEN (statement)|SCREEN]] 9 or 10
**'''_FONT 14''' - default font for [[SCREEN]] 9 or 10
**'''_FONT 16''' - default font for [[SCREEN (statement)|SCREEN]] 0 ({{KW|WIDTH}} 80, 25 text only), 11 or 12
**'''_FONT 16''' - default font for [[SCREEN]] 0 ([[WIDTH]] 80, 25 text only), 11 or 12
**'''_FONT 9, 15''' and '''17''' are the double width versions of 8, 14 and 16 respectively in text '''SCREEN 0'''.
**'''_FONT 9, 15''' and '''17''' are the double width versions of 8, 14 and 16 respectively in text '''SCREEN 0'''.
* If the font handle is invalid (equals -1 or 0), an [[ERROR Codes|error]] will occur. '''Check handle values before using or freeing them.'''
* If the font handle is invalid (equals -1 or 0), an [[ERROR Codes|error]] will occur. '''Check handle values before using or freeing them.'''
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''Example 1:'' Previews and creates a file list of valid MONOSPACE TTF fonts by checking the [[_LOADFONT]] handle values.
''Example 1:'' Previews and creates a file list of valid MONOSPACE TTF fonts by checking the [[_LOADFONT]] handle values.
{{CodeStart}}
{{CodeStart}}
{{Cl|SCREEN (statement)|SCREEN}} 12
{{Cl|SCREEN}} {{Text|12|#F580B1}}
path$ = "C:\WINDOWS\Fonts\"                 'path to the font folder
path$ = {{Text|<nowiki>"C:\WINDOWS\Fonts\"</nowiki>|#FFB100}} {{Text|<nowiki>'path to the font folder</nowiki>|#919191}}
{{Cl|SHELL}} {{Cl|_HIDE}} "DIR /b " + path$ + "\*.ttf > TTFonts.INF"
{{Cl|SHELL}} {{Cl|_HIDE}} {{Text|<nowiki>"DIR /b "</nowiki>|#FFB100}} + path$ + {{Text|<nowiki>"\*.ttf > TTFonts.INF"</nowiki>|#FFB100}}
style$ = "monospace"                         'set style to MONOSPACE
style$ = {{Text|<nowiki>"monospace"</nowiki>|#FFB100}} {{Text|<nowiki>'set style to MONOSPACE</nowiki>|#919191}}
{{Cl|OPEN}} "TTFonts.INF" {{Cl|FOR (file statement)|FOR}} {{Cl|INPUT (file mode)|INPUT}} {{Cl|AS}} #1           'list of TTF fonts only
{{Cl|OPEN}} {{Text|<nowiki>"TTFonts.INF"</nowiki>|#FFB100}} {{Cl|OPEN#File_Access_Modes|FOR}} {{Cl|OPEN#File_Access_Modes|INPUT}} {{Cl|OPEN|AS}} #1 {{Text|<nowiki>'list of TTF fonts only</nowiki>|#919191}}
{{Cl|OPEN}} "TTFMono.INF" {{Cl|FOR (file statement)|FOR}} {{Cl|OUTPUT}} {{Cl|AS}} #2         'will hold list of valid MONOSPACE fonts
{{Cl|OPEN}} {{Text|<nowiki>"TTFMono.INF"</nowiki>|#FFB100}} {{Cl|OPEN#File_Access_Modes|FOR}} {{Cl|OPEN#File_Access_Modes|OUTPUT}} {{Cl|OPEN|AS}} #2 {{Text|<nowiki>'will hold list of valid MONOSPACE fonts</nowiki>|#919191}}


{{Cl|DO}} {{Cl|UNTIL}} {{Cl|EOF}}(1): found = found + 1
{{Cl|DO...LOOP|DO UNTIL}} {{Cl|EOF}}({{Text|1|#F580B1}}): found = found + {{Text|1|#F580B1}}
  {{Cl|LINE INPUT (file statement)|LINE INPUT}} #1, font$
    {{Cl|LINE INPUT (file statement)|LINE INPUT}} #1, font$
  f& ={{Cl|_LOADFONT}}(path$ + font$, 30, style$)
    f& = {{Cl|_LOADFONT}}(path$ + font$, {{Text|30|#F580B1}}, style$)
  {{Cl|IF}} f& > 0 {{Cl|THEN}}                 'check for valid handle values > 0
    {{Cl|IF}} f& > {{Text|0|#F580B1}} {{Cl|THEN}} {{Text|<nowiki>'check for valid handle values > 0</nowiki>|#919191}}
    OK = OK + 1
        OK = OK + {{Text|1|#F580B1}}
    {{Cl|PRINT (file statement)|PRINT}} #2, font$
        {{Cl|PRINT (file statement)|PRINT}} #2, font$
    {{Cl|_FONT}} f&                     'will create error if handle is invalid!
        {{Cl|_FONT}} f& {{Text|<nowiki>'will create error if handle is invalid!</nowiki>|#919191}}
    {{Cl|PRINT}} "Hello World!"
        {{Cl|PRINT}} {{Text|<nowiki>"Hello World!"</nowiki>|#FFB100}}
    {{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} font$; f&
        {{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} font$; f&
    {{Cl|PRINT}} "Press any key."
        {{Cl|PRINT}} {{Text|<nowiki>"Press any key."</nowiki>|#FFB100}}
    K$ = {{Cl|INPUT$}}(1)
        K$ = {{Cl|INPUT$}}({{Text|1|#F580B1}})
    {{Cl|_FONT}} 16                     'use QB64 default font to free tested font
        {{Cl|_FONT}} {{Text|16|#F580B1}} {{Text|<nowiki>'use QB64 default font to free tested font</nowiki>|#919191}}
    {{Cl|_FREEFONT}} f&                 'returns an error if handle <= 0!
        {{Cl|_FREEFONT}} f& {{Text|<nowiki>'returns an error if handle <= 0!</nowiki>|#919191}}
    {{Cl|CLS}}
        {{Cl|CLS}}
  {{Cl|END IF}}
    {{Cl|END IF}}
  {{Cl|PRINT}}
    {{Cl|PRINT}}
{{Cl|IF}} K$ = {{Cl|CHR$}}(27) {{Cl|THEN}} {{Cl|EXIT DO}}
    {{Cl|IF}} K$ = {{Cl|CHR$}}({{Text|27|#F580B1}}) {{Cl|THEN}} {{Cl|EXIT DO}}
{{Cl|LOOP}}
{{Cl|LOOP}}
{{Cl|CLOSE}}
{{Cl|CLOSE}}
{{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} "Found"; found; "TTF files,"; OK; "can use Monospace,"
{{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} {{Text|<nowiki>"Found"</nowiki>|#FFB100}}; found; {{Text|<nowiki>"TTF files,"</nowiki>|#FFB100}}; OK; {{Text|<nowiki>"can use Monospace,"</nowiki>|#FFB100}}
{{Cl|END}}
{{Cl|END}}
{{CodeEnd}}
{{CodeEnd}}
{{small|Code by Ted Weissgerber}}
{{Small|Code by Ted Weissgerber}}
{{OutputStart}}
{{OutputStart}}
Found 106 TTF files, 13 can use Monospace.
Found 106 TTF files, 13 can use Monospace.
{{OutputEnd}}
{{OutputEnd}}


----


''Example 2:'' Using a _FREEFONT sub-procedure.
''Example 2:'' Using a _FREEFONT sub-procedure.
{{CodeStart}}
{{CodeStart}}
fontpath$ = {{Cl|ENVIRON$}}("SYSTEMROOT") + "\fonts\lucon.ttf"
fontpath$ = {{Cl|ENVIRON$}}({{Text|<nowiki>"SYSTEMROOT"</nowiki>|#FFB100}}) + {{Text|<nowiki>"\fonts\lucon.ttf"</nowiki>|#FFB100}}
style$ = "MONOSPACE, ITALIC, BOLD"
style$ = {{Text|<nowiki>"MONOSPACE, ITALIC, BOLD"</nowiki>|#FFB100}}
fontsize% = 20
fontsize% = {{Text|20|#F580B1}}


{{Cl|_FONT|_FONT }}16
{{Cl|_FONT}} {{Text|16|#F580B1}}
{{Cl|PRINT}}
{{Cl|PRINT}}
{{Cl|PRINT}} "This is the QB64 default {{Cl|_FONT|_FONT }}16! To change, press any key!"
{{Cl|PRINT}} {{Text|<nowiki>"This is the QB64 default _FONT 16! To change, press any key!"</nowiki>|#FFB100}}
{{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|INKEY$}} <> ""
{{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|DO...LOOP|LOOP UNTIL}} {{Cl|INKEY$}} <> {{Text|<nowiki>""</nowiki>|#FFB100}}


{{Cl|GOSUB}} ClearFont 'call will not free anything if font& = 0
{{Cl|GOSUB}} ClearFont {{Text|<nowiki>'call will not free anything if font& = 0</nowiki>|#919191}}


font& = {{Cl|_LOADFONT}}(fontpath$, fontsize%, style$)
font& = {{Cl|_LOADFONT}}(fontpath$, fontsize%, style$)
{{Cl|IF}} font > 0 THEN {{Cl|_FONT|_FONT}} font& 'NEVER try to load a font value less than 1!
{{Cl|IF}} font > {{Text|0|#F580B1}} {{Cl|THEN}} {{Cl|_FONT}} font& {{Text|<nowiki>'NEVER try to load a font value less than 1!</nowiki>|#919191}}
{{Cl|PRINT}}
{{Cl|PRINT}}
{{Cl|PRINT}} "A NEW {{Cl|_FONT|_FONT}} style. To change to default, press any key!"
{{Cl|PRINT}} {{Text|<nowiki>"A NEW _FONT style. To change to default, press any key!"</nowiki>|#FFB100}}
{{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|INKEY$}} <> ""
{{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|DO...LOOP|LOOP UNTIL}} {{Cl|INKEY$}} <> {{Text|<nowiki>""</nowiki>|#FFB100}}


{{Cl|GOSUB}} ClearFont 'call will free a valid font handle from memory
{{Cl|GOSUB}} ClearFont {{Text|<nowiki>'call will free a valid font handle from memory</nowiki>|#919191}}


{{Cl|END}}
{{Cl|END}}


ClearFont:
ClearFont:
{{Cl|IF}} font& > 0 {{Cl|THEN}}
{{Cl|IF}} font& > {{Text|0|#F580B1}} {{Cl|THEN}}
     {{Cl|_FONT|_FONT }}16  'change used font to the QB64 8x16 default font
     {{Cl|_FONT}} {{Text|16|#F580B1}} {{Text|<nowiki>'change used font to the QB64 8x16 default font</nowiki>|#919191}}
     {{Cl|_FREEFONT}} font&
     {{Cl|_FREEFONT}} font&
     {{Cl|PRINT}}: {{Cl|PRINT}} "The previous font was freed with _FREEFONT!"
     {{Cl|PRINT}}: {{Cl|PRINT}} {{Text|<nowiki>"The previous font was freed with _FREEFONT!"</nowiki>|#FFB100}}
{{Cl|ELSE}} : {{Cl|PRINT}}: {{Cl|PRINT}} "_FREEFONT was not used!"
{{Cl|ELSE}}: {{Cl|PRINT}}: {{Cl|PRINT}} {{Text|<nowiki>"_FREEFONT was not used!"</nowiki>|#FFB100}}
{{Cl|END IF}}
{{Cl|END IF}}
{{Cl|RETURN}}
{{Cl|RETURN}}

Latest revision as of 10:24, 29 March 2023

The _FREEFONT statement frees a font handle that was created by _LOADFONT.


Syntax

_FREEFONT (fontHandle&)


Description

  • Unloads fonts that are no longer in use or needed in order to free program memory and resources.
  • You cannot free a font which is in use. Change the font to a QB64 default font size before freeing the handle (see example below).
  • Predefined QB64 font handle numbers can be used before freeing a font:
    • _FONT 8 - default font for SCREEN 1, 2, 7, 8 or 13
    • _FONT 14 - default font for SCREEN 9 or 10
    • _FONT 16 - default font for SCREEN 0 (WIDTH 80, 25 text only), 11 or 12
    • _FONT 9, 15 and 17 are the double width versions of 8, 14 and 16 respectively in text SCREEN 0.
  • If the font handle is invalid (equals -1 or 0), an error will occur. Check handle values before using or freeing them.
  • You cannot free inbuilt/default QB64 fonts nor do they ever need freed.


Examples

Example 1: Previews and creates a file list of valid MONOSPACE TTF fonts by checking the _LOADFONT handle values. 

SCREEN 12
path$ = "C:\WINDOWS\Fonts\" 'path to the font folder
SHELL _HIDE "DIR /b " + path$ + "\*.ttf > TTFonts.INF"
style$ = "monospace" 'set style to MONOSPACE
OPEN "TTFonts.INF" FOR INPUT AS #1 'list of TTF fonts only
OPEN "TTFMono.INF" FOR OUTPUT AS #2 'will hold list of valid MONOSPACE fonts

DO UNTIL EOF(1): found = found + 1
    LINE INPUT #1, font$
    f& = _LOADFONT(path$ + font$, 30, style$)
    IF f& > 0 THEN 'check for valid handle values > 0
        OK = OK + 1
        PRINT #2, font$
        _FONT f& 'will create error if handle is invalid!
        PRINT "Hello World!"
        PRINT: PRINT: PRINT font$; f&
        PRINT "Press any key."
        K$ = INPUT$(1)
        _FONT 16 'use QB64 default font to free tested font
        _FREEFONT f& 'returns an error if handle <= 0!
        CLS
    END IF
    PRINT
    IF K$ = CHR$(27) THEN EXIT DO
LOOP
CLOSE
PRINT: PRINT: PRINT "Found"; found; "TTF files,"; OK; "can use Monospace,"
END
Code by Ted Weissgerber
Found 106 TTF files, 13 can use Monospace.

Example 2: Using a _FREEFONT sub-procedure. 

fontpath$ = ENVIRON$("SYSTEMROOT") + "\fonts\lucon.ttf"
style$ = "MONOSPACE, ITALIC, BOLD"
fontsize% = 20

_FONT 16
PRINT
PRINT "This is the QB64 default _FONT 16! To change, press any key!"
DO: SLEEP: LOOP UNTIL INKEY$ <> ""

GOSUB ClearFont 'call will not free anything if font& = 0

font& = _LOADFONT(fontpath$, fontsize%, style$)
IF font > 0 THEN _FONT font& 'NEVER try to load a font value less than 1!
PRINT
PRINT "A NEW _FONT style. To change to default, press any key!"
DO: SLEEP: LOOP UNTIL INKEY$ <> ""

GOSUB ClearFont 'call will free a valid font handle from memory

END

ClearFont:
IF font& > 0 THEN
    _FONT 16 'change used font to the QB64 8x16 default font
    _FREEFONT font&
    PRINT: PRINT "The previous font was freed with _FREEFONT!"
ELSE: PRINT: PRINT "_FREEFONT was not used!"
END IF
RETURN


See also


Navigation:
Main Page with Articles and Tutorials
Keyword Reference - Alphabetical
Keyword Reference - By usage
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