Difference between revisions of "DISPLAY (function)"

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imported>SMcNeill
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The _DISPLAY function returns the handle of the current image that is displayed on the screen.
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{{DISPLAYTITLE:_DISPLAY (function)}}
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The [[_DISPLAY]] function returns the handle of the current image that is displayed on the screen.
  
''Syntax:'' displayedimage = _DISPLAY
 
  
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{{PageSyntax}}
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:{{Parameter|currentImage&}} = [[_DISPLAY]]
  
  
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{{PageDescription}}
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* Returns the current image handle value that is being displayed. Returns 0 if in the default [[SCREEN|screen]] image.
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* Not to be confused with the [[_DISPLAY]] statement that displays the screen when not using [[_AUTODISPLAY]].
  
''See also:'' [[SCREEN]] (note the QB64 use of SCREEN to set which image to display)
 
  
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{{PageExamples}}
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''Example:'' Creating a mouse cursor using a page number that '''you create''' in memory without setting up page flipping.
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{{CodeStart}}
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{{Cl|SCREEN}} {{Cl|_NEWIMAGE}}(640, 480, 32) 'any graphics mode should work without setting up pages
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{{Cl|_MOUSEHIDE}}
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SetupCursor
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{{Cl|PRINT}} "Hello World!"
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{{Cl|DO}}: {{Cl|_LIMIT}} 30
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  {{Cl|DO}} {{Cl|WHILE}} {{Cl|_MOUSEINPUT}}: {{Cl|LOOP}} 'main loop must contain _MOUSEINPUT 
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'      other program code   
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{{Cl|LOOP}}
  
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{{Cl|SUB}} SetupCursor
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{{Cl|ON TIMER(n)|ON TIMER}}(0.02) UpdateCursor
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{{Cl|TIMER}} ON
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{{Cl|END SUB}}
  
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{{Cl|SUB}} UpdateCursor
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{{Cl|PCOPY}} {{Cl|_DISPLAY (function)|_DISPLAY}}, 100  'any page number as desination with the _DISPLAY function as source
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{{Cl|PSET}} ({{Cl|_MOUSEX}}, {{Cl|_MOUSEY}}), {{Cl|_RGB}}(0, 255, 0)
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{{Cl|DRAW}} "ND10F10L3F5L4H5L3"
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{{Cl|_DISPLAY}}                  'statement shows image
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{{Cl|PCOPY}} 100, {{Cl|_DISPLAY (function)|_DISPLAY}} 'with the function return as destination page
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{{Cl|END SUB}} '' ''
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{{CodeEnd}}
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''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.
  
==Navigation:==
 
  
[[Keyword_Reference_-_Alphabetical|Go to Keyword Reference - Alphabetical]]
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{{PageSeeAlso}}
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* [[SCREEN]]
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* [[PCOPY]]
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* [[_DISPLAY]] {{text|(statement)}}
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* [[_AUTODISPLAY]] {{text|(default mode)}}
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* [[_DISPLAYORDER]] {{text|(statement)}}
  
[[Keyword Reference - By usage|Go to Keyword Reference - By usage]]
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{{PageNavigation}}

Latest revision as of 20:46, 24 September 2017

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



Navigation:
Keyword Reference - Alphabetical
Keyword Reference - By Usage
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