FREEIMAGE: Difference between revisions

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* '''It is important to free unused or unneeded images with [[_FREEIMAGE]] to prevent memory overflow errors.'''
* '''It is important to free unused or unneeded images with [[_FREEIMAGE]] to prevent memory overflow errors.'''
* '''Do not try to free image handles currently being used as the active [[SCREEN]]. Change screen modes first.'''
* '''Do not try to free image handles currently being used as the active [[SCREEN]]. Change screen modes first.'''
 
* '''Note that calling _FREEIMAGE only frees the handle.  It does NOT reset the variable used to store the handle back to 0.  (This is because 0 is often used as a short cut value for the current display, such as with _DEST 0.)'''


{{PageExamples}}
{{PageExamples}}
''Example:'' Loading a program splash screen and freeing image when no longer necessary:
''Example:'' Loading a program splash screen and freeing image when no longer necessary:
{{CodeStart}}
{{CodeStart}}
s& = {{Cl|_LOADIMAGE}}("SPLASH.BMP",32) 'load 32 bit(24 BPP) image
s& = {{Cl|_LOADIMAGE}}({{Text|<nowiki>"SPLASH.BMP"</nowiki>|#FFB100}}, {{Text|32|#F580B1}}) {{Text|<nowiki>'load 32 bit(24 BPP) image</nowiki>|#919191}}
{{Cl|IF}} s& < -1 THEN {{Cl|SCREEN (statement)|SCREEN}} s&   'use image as a 32 bit SCREEN
{{Cl|IF}} s& < {{Text|-1|#F580B1}} {{Cl|THEN}} {{Cl|SCREEN}} s& {{Text|<nowiki>'use image as a 32 bit SCREEN</nowiki>|#919191}}
{{Cl|_DELAY}} 6                         'display splash screen for 6 seconds
{{Cl|_DELAY}} {{Text|6|#F580B1}} {{Text|<nowiki>'display splash screen for 6 seconds</nowiki>|#919191}}
{{Cl|SCREEN (statement)|SCREEN}} 0      'MUST change screen mode before freeing a SCREEN image!
{{Cl|SCREEN}} {{Text|0|#F580B1}} {{Text|<nowiki>'MUST change screen mode before freeing a SCREEN image!</nowiki>|#919191}}
{{Cl|IF}} s& < -1 THEN {{Cl|_FREEIMAGE}} s& 'handle value MUST be less than -1 or error!
{{Cl|IF}} s& < {{Text|-1|#F580B1}} {{Cl|THEN}} {{Cl|_FREEIMAGE}} s& {{Text|<nowiki>'handle value MUST be less than -1 or error!</nowiki>|#919191}}
{{Cl|CLS}}
{{Cl|CLS}}
{{CodeEnd}}
{{CodeEnd}}
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* [[_SCREENIMAGE]]
* [[_SCREENIMAGE]]
* [[_COPYIMAGE]]
* [[_COPYIMAGE]]
* [[_SAVEIMAGE]]




{{PageNavigation}}
{{PageNavigation}}

Latest revision as of 08:21, 10 January 2024

The _FREEIMAGE statement releases the designated file image created by the _LOADIMAGE, _NEWIMAGE or _COPYIMAGE functions from memory when they are no longer needed.


Syntax

_FREEIMAGE [handle&]


Description

  • If handle& is omitted, the current destination image is freed from memory.
  • Freeing the destination image or source image will result in the display page being selected instead.
  • Invalid image handle values of -1 or 0 cannot be freed or an "Illegal Function" error will occur. Check the handle value first.
  • SCREEN modes in use cannot be freed or an "Illegal Function" error will occur. Change SCREEN modes before freeing.
  • Once a specific image handle is no longer used or referenced by your program, it can be freed with _FREEIMAGE.
  • Images are not deallocated when the SUB or FUNCTION they are created in ends. Free them with _FREEIMAGE.
  • It is important to free unused or unneeded images with _FREEIMAGE to prevent memory overflow errors.
  • Do not try to free image handles currently being used as the active SCREEN. Change screen modes first.
  • Note that calling _FREEIMAGE only frees the handle. It does NOT reset the variable used to store the handle back to 0. (This is because 0 is often used as a short cut value for the current display, such as with _DEST 0.)

Examples

Example: Loading a program splash screen and freeing image when no longer necessary:

s& = _LOADIMAGE("SPLASH.BMP", 32) 'load 32 bit(24 BPP) image
IF s& < -1 THEN SCREEN s& 'use image as a 32 bit SCREEN
_DELAY 6 'display splash screen for 6 seconds
SCREEN 0 'MUST change screen mode before freeing a SCREEN image!
IF s& < -1 THEN _FREEIMAGE s& 'handle value MUST be less than -1 or error!
CLS
Note: A valid image file name must be used by _LOADIMAGE or the invalid handle memory value will not need to be freed.


See also



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