_DISPLAY (function)

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The _DISPLAY function returns the handle of the current image that is displayed on the screen.


Syntax

currentImage& = _DISPLAY


Description

  • Returns the current image handle value that is being displayed. Returns 0 if in the default screen image.
  • Not to be confused with the _DISPLAY statement that displays the screen when not using _AUTODISPLAY.


Examples

Example: Creating a mouse cursor using a page number that you create in memory without setting up page flipping.

SCREEN _NEWIMAGE(640, 480, 32) 'any graphics mode should work without setting up pages
_MOUSEHIDE
SetupCursor
PRINT "Hello World!"
DO: _LIMIT 30
    DO WHILE _MOUSEINPUT: LOOP 'main loop must contain _MOUSEINPUT
    '       other program code
LOOP

SUB SetupCursor
    ON TIMER(0.02) UpdateCursor
    TIMER ON
END SUB

SUB UpdateCursor
    PCOPY _DISPLAY, 100 'any page number as desination with the _DISPLAY function as source
    PSET (_MOUSEX, _MOUSEY), _RGB(0, 255, 0)
    DRAW "ND10F10L3F5L4H5L3"
    _DISPLAY 'statement shows image
    PCOPY 100, _DISPLAY 'with the function return as destination page
END SUB

Note: Works with the _DISPLAY function return as the other page. If mouse reads are not crucial, put the _MOUSEINPUT loop inside of the UpdateCursor SUB.


See also



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