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(Created page with "{{DISPLAYTITLE:_FREEFONT}} The _FREEFONT statement frees a font handle that was created by _LOADFONT. {{PageSyntax}} :_FREEFONT ({{Parameter|fontHandle&}}) {{PageDescription}} * 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...") |
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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 [[ | **'''_FONT 8 ''' - default font for [[SCREEN]] 1, 2, 7, 8 or 13 | ||
**'''_FONT 14''' - default font for [[ | **'''_FONT 14''' - default font for [[SCREEN]] 9 or 10 | ||
**'''_FONT 16''' - default font for [[ | **'''_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.''' | ||
* You cannot free inbuilt/default QB64 fonts nor do they ever need freed. | * You cannot free inbuilt/default QB64 fonts nor do they ever need freed. | ||
{{PageExamples}} | {{PageExamples}} | ||
''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 | {{Cl|SCREEN}} {{Text|12|#F580B1}} | ||
path$ = "C:\WINDOWS\Fonts\" | 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" | style$ = {{Text|<nowiki>"monospace"</nowiki>|#FFB100}} {{Text|<nowiki>'set style to MONOSPACE</nowiki>|#919191}} | ||
{{Cl|OPEN}} "TTFonts.INF" {{Cl| | {{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| | {{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| | {{Cl|DO...LOOP|DO UNTIL}} {{Cl|EOF}}({{Text|1|#F580B1}}): found = found + {{Text|1|#F580B1}} | ||
{{Cl|LINE INPUT (file statement)|LINE INPUT}} #1, font$ | |||
f& = {{Cl|_LOADFONT}}(path$ + font$, {{Text|30|#F580B1}}, style$) | |||
{{Cl|IF}} f& > {{Text|0|#F580B1}} {{Cl|THEN}} {{Text|<nowiki>'check for valid handle values > 0</nowiki>|#919191}} | |||
OK = OK + {{Text|1|#F580B1}} | |||
{{Cl|PRINT (file statement)|PRINT}} #2, font$ | |||
{{Cl|_FONT}} f& {{Text|<nowiki>'will create error if handle is invalid!</nowiki>|#919191}} | |||
{{Cl|PRINT}} {{Text|<nowiki>"Hello World!"</nowiki>|#FFB100}} | |||
{{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} font$; f& | |||
{{Cl|PRINT}} {{Text|<nowiki>"Press any key."</nowiki>|#FFB100}} | |||
K$ = {{Cl|INPUT$}}({{Text|1|#F580B1}}) | |||
{{Cl|_FONT}} {{Text|16|#F580B1}} {{Text|<nowiki>'use QB64 default font to free tested font</nowiki>|#919191}} | |||
{{Cl|_FREEFONT}} f& {{Text|<nowiki>'returns an error if handle <= 0!</nowiki>|#919191}} | |||
{{Cl|CLS}} | |||
{{Cl|END IF}} | |||
{{Cl|PRINT}} | |||
{{Cl|IF}} K$ = {{Cl|CHR$}}(27) {{Cl|THEN}} {{Cl|EXIT DO}} | {{Cl|IF}} K$ = {{Cl|CHR$}}({{Text|27|#F580B1}}) {{Cl|THEN}} {{Cl|EXIT DO}} | ||
{{Cl|LOOP}} | {{Cl|LOOP}} | ||
{{Cl|CLOSE}} | {{Cl|CLOSE}} | ||
{{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} "Found"; found; "TTF files,"; OK; "can use Monospace," | {{Cl|PRINT}}: {{Cl|PRINT}}: {{Cl|PRINT}} {{Text|<nowiki>"Found"</nowiki>|#FFB100}}; found; {{Text|<nowiki>"TTF files,"</nowiki>|#FFB100}}; OK; {{Text|<nowiki>"can use Monospace,"</nowiki>|#FFB100}} | ||
{{Cl|END}} | {{Cl|END}} | ||
{{CodeEnd}} | {{CodeEnd}} | ||
{{ | {{Small|Code by Ted Weissgerber}} | ||
{{OutputStart}} | {{OutputStart}} | ||
Found 106 TTF files, 13 can use Monospace. | Found 106 TTF files, 13 can use Monospace. | ||
{{OutputEnd}} | {{OutputEnd}} | ||
---- | |||
''Example 2:'' Using a _FREEFONT sub-procedure. | ''Example 2:'' Using a _FREEFONT sub-procedure. | ||
{{CodeStart}} | {{CodeStart}} | ||
fontpath$ = {{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| | {{Cl|_FONT}} {{Text|16|#F580B1}} | ||
{{Cl|PRINT}} | {{Cl|PRINT}} | ||
{{Cl|PRINT}} "This is the QB64 default | {{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|DO}}: {{Cl|SLEEP}}: {{Cl|DO...LOOP|LOOP UNTIL}} {{Cl|INKEY$}} <> {{Text|<nowiki>""</nowiki>|#FFB100}} | ||
{{Cl|GOSUB}} ClearFont | {{Cl|GOSUB}} ClearFont {{Text|<nowiki>'call will not free anything if font& = 0</nowiki>|#919191}} | ||
font& = {{Cl|_LOADFONT}}(fontpath$, fontsize%, style$) | font& = {{Cl|_LOADFONT}}(fontpath$, fontsize%, style$) | ||
{{Cl|IF}} font > 0 THEN {{Cl | {{Cl|IF}} font > {{Text|0|#F580B1}} {{Cl|THEN}} {{Cl|_FONT}} font& {{Text|<nowiki>'NEVER try to load a font value less than 1!</nowiki>|#919191}} | ||
{{Cl|PRINT}} | {{Cl|PRINT}} | ||
{{Cl|PRINT}} "A NEW | {{Cl|PRINT}} {{Text|<nowiki>"A NEW _FONT style. To change to default, press any key!"</nowiki>|#FFB100}} | ||
{{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|LOOP | {{Cl|DO}}: {{Cl|SLEEP}}: {{Cl|DO...LOOP|LOOP UNTIL}} {{Cl|INKEY$}} <> {{Text|<nowiki>""</nowiki>|#FFB100}} | ||
{{Cl|GOSUB}} ClearFont | {{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| | {{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}} | ||
{{CodeEnd}} | {{CodeEnd}} | ||
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:
- 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$(27) THEN EXIT DO LOOP CLOSE PRINT: PRINT: PRINT "Found"; found; "TTF files,"; OK; "can use Monospace," END |
Found 106 TTF files, 13 can use Monospace. |
Example 2: Using a _FREEFONT sub-procedure.
fontpath$ = 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