1
1
Fork 0
mirror of https://github.com/QB64-Phoenix-Edition/QB64pe.git synced 2024-06-29 10:30:36 +00:00
QB64-PE/internal/help/_COPYIMAGE.txt
SteveMcNeill 33adc04fc4 Add temp folder to repo. It's necessary as well!
Just more initial setting on... nothing much to see here.
2022-04-28 13:39:56 -04:00

74 lines
3.3 KiB
Plaintext

{{DISPLAYTITLE:_COPYIMAGE}}
The [[_COPYIMAGE]] function creates an identical designated image in memory with a different negative [[LONG]] handle value.
{{PageSyntax}}
: newhandle& = [[_COPYIMAGE]][({{Parameter|imageHandle&}}[, {{Parameter|mode%}})]]
{{Parameters}}
* The [[LONG]] ''newhandle&'' value returned will be different than the source handle value supplied.
* If ''imageHandle&'' parameter is omitted or zero is designated, the current software [[_DEST|destination]] screen or image is copied.
* If 1 is designated instead of an ''imageHandle&'', it designates the last OpenGL hardware surface to copy.
* ''Mode'' 32 can be used to convert 256 color images to 32 bit colors.
* ''Mode'' 33 images are hardware accelerated in '''version 1.000 and up''', and are created using [[_LOADIMAGE]] or [[_COPYIMAGE]].
{{PageDescription}}
* The function copies any image or screen handle to a new and unique negative [[LONG]] handle value.
* Valid copy handles are less than -1. Invalid handles return -1 or 0 if it was never created.
* Every attribute of the passed image or program screen is copied to a new handle value in memory.
* '''32 bit screen surface backgrounds (black) have zero [[_ALPHA]] so that they are transparent when placed over other surfaces.'''
: Use [[CLS]] or [[_DONTBLEND]] to make a new surface background [[_ALPHA]] 255 or opaque.
* '''Images are not deallocated when the [[SUB]] or [[FUNCTION]] they are created in ends. Free them with [[_FREEIMAGE]].'''
* '''It is important to free discarded images with [[_FREEIMAGE]] to prevent PC memory allocation errors!'''
* '''Do not try to free image handles currently being used as the active [[SCREEN]]. Change screen modes first.'''
{{PageExamples}}
''Example:'' Restoring a Legacy SCREEN using the _COPYIMAGE return value.
{{CodeStart}}'' ''
{{Cl|SCREEN}} 13
{{Cl|CIRCLE}} (160, 100), 100, 40
DO: {{Cl|SLEEP}}: {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|INKEY$}} <> ""
'backup screen before changing {{Cl|SCREEN}} mode
oldmode& = {{Cl|_COPYIMAGE}}(0) 'the 0 value designates the current destination {{Cl|SCREEN}}
s& = {{Cl|_NEWIMAGE}}(800, 600, 32)
{{Cl|SCREEN}} s&
{{Cl|LINE}} (100, 100)-(500, 500), {{Cl|_RGB}}(0, 255, 255), BF
DO: {{Cl|SLEEP}}: {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|INKEY$}} <> ""
{{Cl|SCREEN}} oldmode& 'restore original screen
{{Cl|IF...THEN|IF}} s& < -1 THEN {{Cl|_FREEIMAGE}} s&
{{Cl|END}} '' ''
{{CodeEnd}}
: ''Note:'' Only free valid handle values with [[_FREEIMAGE]] AFTER a new [[SCREEN]] mode is being used by the program.
''Example 2:'' Program that copies desktop to a hardware image to form a 3D triangle ('''version 1.000 and up'''):
{{CodeStart}} '' ''
{{Cl|SCREEN}} {{Cl|_NEWIMAGE}}(640, 480, 32)
my_hardware_handle = {{Cl|_COPYIMAGE}}({{Cl|_SCREENIMAGE}}, 33) 'take a screenshot and use it as our texture
{{Cl|_MAPTRIANGLE}} (0, 0)-(500, 0)-(250, 500), my_hardware_handle TO_
(-1, 0, -1)-(1, 0, -1)-(0, 5, -10), , _SMOOTH
{{Cl|_DISPLAY}}
{{Cl|DO...LOOP|DO}}: {{Cl|_LIMIT}} 30: {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|INKEY$}} <> "" '' ''
{{CodeEnd}}{{small|Code courtesy of Galleon}}
{{PageSeeAlso}}
* [[_LOADIMAGE]], [[_NEWIMAGE]]
* [[_PUTIMAGE]], [[_MAPTRIANGLE]]
* [[_SOURCE]], [[_DEST]]
* [[_FREEIMAGE]]
* [[_FILELIST$ (function)]] {{text|(Demo of _COPYIMAGE)}}
* [[_DISPLAYORDER]]
* [[Hardware images]]
{{PageNavigation}}
<