RGBA32: Difference between revisions

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{{PageDescription}}
{{PageDescription}}
* The value returned is a 32-bit [[_UNSIGNED]] [[LONG]] color value.  
* The value returned is a 32-bit [[_UNSIGNED]] [[LONG]] color value.
* '''Return variable types must be [[_UNSIGNED]] [[LONG]] or resulting color may lose the [[_BLUE]] value.'''
* '''Return variable types must be [[_UNSIGNED]] [[LONG]] or resulting color may lose the [[_BLUE]] value.'''
* {{Parameter|red&}} specifies the red component intensity from 0 to 255.
* {{Parameter|red&}} specifies the red component intensity from 0 to 255.
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* {{Parameter|alpha&}} specifies the [[_ALPHA|''alpha'']] component transparency value from 0 (fully transparent) to 255 (opaque).
* {{Parameter|alpha&}} specifies the [[_ALPHA|''alpha'']] component transparency value from 0 (fully transparent) to 255 (opaque).
* Alpha or intensity values outside of the valid range of 0 to 255 are clipped.
* Alpha or intensity values outside of the valid range of 0 to 255 are clipped.
* Returns [[LONG]] 32-bit hexadecimal values from '''&H00{{text|00|red}}{{text|00|green}}{{text|00|blue}}''' to '''&HFF{{text|FF|red}}{{text|FF|green}}{{text|FF|blue}}''' with varying [[_ALPHA]] transparency.
* Returns [[LONG]] 32-bit hexadecimal values from '''&H00{{Text|00|red}}{{Text|00|green}}{{Text|00|blue}}''' to '''&HFF{{Text|FF|red}}{{Text|FF|green}}{{Text|FF|blue}}''' with varying [[_ALPHA]] transparency.
* When [[LONG]] values are [[PUT]] to file, the ARGB values become BGRA. Use [[LEFT$]]([[MKL$]]({{Parameter|color32value~&}}), 3) to place 3 colors.
* When [[LONG]] values are [[PUT]] to file, the ARGB values become BGRA. Use [[LEFT$]]([[MKL$]]({{Parameter|color32value~&}}), 3) to place 3 colors.
* '''NOTE: Default 32-bit backgrounds are clear black or [[_RGBA]](0, 0, 0, 0). Use [[CLS]] to make the black opaque.'''
* '''NOTE: Default 32-bit backgrounds are clear black or [[_RGBA]](0, 0, 0, 0). Use [[CLS]] to make the black opaque.'''
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{{PageExamples}}
{{PageExamples}}
''Example:'' Changing the [[ALPHA]] value to fade an image in and out using a 32 bit PNG image.
''Example:'' Changing the [[ALPHA]] value to fade an image in and out using a 32 bit PNG image.
{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|SCREEN (statement)|SCREEN}} {{Cl|_NEWIMAGE}}(600, 400, 32)
{{Cl|SCREEN}} {{Cl|_NEWIMAGE}}(600, 400, 32)


img& = {{Cl|_LOADIMAGE}}("qb64_trans.png")  'use any 24/32 bit image
img& = {{Cl|_LOADIMAGE}}("qb64_trans.png")  'use any 24/32 bit image
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' Fade in
' Fade in
{{Cl|FOR...NEXT|FOR}} i% = 255 {{Cl|TO}} 0 {{Cl|STEP}} -5
{{Cl|FOR...NEXT|FOR}} i% = 255 {{Cl|TO}} 0 {{Cl|STEP}} -5
   {{Cl|_LIMIT}} 20                          'control fade speed  
   {{Cl|_LIMIT}} 20                          'control fade speed
   {{Cl|_PUTIMAGE}} (0, 0)-(600, 400), img&
   {{Cl|_PUTIMAGE}} (0, 0)-(600, 400), img&
   {{Cl|LINE}} (0, 0)-(600, 400), {{Cl|_RGBA}}(0, 0, 0, i%), BF 'decrease black box transparency
   {{Cl|LINE}} (0, 0)-(600, 400), {{Cl|_RGBA}}(0, 0, 0, i%), BF 'decrease black box transparency
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' Fade out
' Fade out
{{Cl|FOR...NEXT|FOR}} i% = 0 {{Cl|TO}} 255 {{Cl|STEP}} 5
{{Cl|FOR...NEXT|FOR}} i% = 0 {{Cl|TO}} 255 {{Cl|STEP}} 5
   {{Cl|_LIMIT}} 20                          'control fade speed  
   {{Cl|_LIMIT}} 20                          'control fade speed
   {{Cl|_PUTIMAGE}} (0, 0)-(600, 400), img&
   {{Cl|_PUTIMAGE}} (0, 0)-(600, 400), img&
   {{Cl|LINE}} (0, 0)-(600, 400), {{Cl|_RGBA}}(0, 0, 0, i%), BF 'increase black box transparency
   {{Cl|LINE}} (0, 0)-(600, 400), {{Cl|_RGBA}}(0, 0, 0, i%), BF 'increase black box transparency
   {{Cl|_DISPLAY}}
   {{Cl|_DISPLAY}}
{{Cl|NEXT}}
{{Cl|NEXT}}
{{Cl|END}} '' ''
{{Cl|END}}
{{CodeEnd}}
{{CodeEnd}}
{{small|Code by Unseen Machine}}
{{Small|Code by Unseen Machine}}




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* [[_RED32]], [[_GREEN32]], [[_BLUE32]]
* [[_RED32]], [[_GREEN32]], [[_BLUE32]]
* [[HEX$ 32 Bit Values]], [[POINT]]
* [[HEX$ 32 Bit Values]], [[POINT]]
* [[SAVEIMAGE]]
* [[SaveImage SUB]]
* [http://www.w3schools.com/html/html_colornames.asp Hexadecimal Color Values]
* [http://www.w3schools.com/html/html_colornames.asp Hexadecimal Color Values]




{{PageNavigation}}
{{PageNavigation}}

Latest revision as of 20:05, 5 January 2024

The _RGBA32 function returns the 32-bit RGBA color value with the specified red, green, blue and alpha component intensities.


Syntax

color32value~& = _RGBA32(red&, green&, blue&, alpha&)


Description

  • The value returned is a 32-bit _UNSIGNED LONG color value.
  • Return variable types must be _UNSIGNED LONG or resulting color may lose the _BLUE value.
  • red& specifies the red component intensity from 0 to 255.
  • green& specifies the green component intensity from 0 to 255.
  • blue& specifies the blue component intensity from 0 to 255.
  • alpha& specifies the alpha component transparency value from 0 (fully transparent) to 255 (opaque).
  • Alpha or intensity values outside of the valid range of 0 to 255 are clipped.
  • Returns LONG 32-bit hexadecimal values from &H00000000 to &HFFFFFFFF with varying _ALPHA transparency.
  • When LONG values are PUT to file, the ARGB values become BGRA. Use LEFT$(MKL$(color32value~&), 3) to place 3 colors.
  • NOTE: Default 32-bit backgrounds are clear black or _RGBA(0, 0, 0, 0). Use CLS to make the black opaque.


Examples

Example: Changing the ALPHA value to fade an image in and out using a 32 bit PNG image. 

SCREEN _NEWIMAGE(600, 400, 32)

img& = _LOADIMAGE("qb64_trans.png")  'use any 24/32 bit image
'Turn off auto display
_DISPLAY

' Fade in
FOR i% = 255 TO 0 STEP -5
  _LIMIT 20                          'control fade speed
  _PUTIMAGE (0, 0)-(600, 400), img&
  LINE (0, 0)-(600, 400), _RGBA(0, 0, 0, i%), BF 'decrease black box transparency
  _DISPLAY
NEXT

' Fade out
FOR i% = 0 TO 255 STEP 5
  _LIMIT 20                          'control fade speed
  _PUTIMAGE (0, 0)-(600, 400), img&
  LINE (0, 0)-(600, 400), _RGBA(0, 0, 0, i%), BF 'increase black box transparency
  _DISPLAY
NEXT
END
Code by Unseen Machine


See also


Navigation:
Main Page with Articles and Tutorials
Keyword Reference - Alphabetical
Keyword Reference - By usage
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