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{{DISPLAYTITLE:_RGB}}
{{DISPLAYTITLE:_RGB}}
The [[_RGB]] function returns the closest palette attribute index (legacy SCREEN modes) OR the [[LONG]] 32-bit color value (32-bit screens).  
The [[_RGB]] function returns the closest palette attribute index (legacy SCREEN modes) OR the [[LONG]] 32-bit color value (32-bit screens).




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{{PageDescription}}
{{PageDescription}}
* The value returned is either the closest color attribute number or a 32-bit [[_UNSIGNED]] [[LONG]] color value.  
* The value returned is either the closest color attribute number or a 32-bit [[_UNSIGNED]] [[LONG]] color value.
* '''Return variable types must be [[LONG]] or resulting color may lose the [[_BLUE]] value.'''
* '''Return variable types must be [[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|blue&}} specifies the blue component intensity from 0 to 255.
* {{Parameter|blue&}} specifies the blue component intensity from 0 to 255.
* Intensity values outside the valid range are clipped.
* Intensity values outside the valid range are clipped.
* Returns [[LONG]] 32-bit hexadecimal values from '''&HFF{{text|00|red}}{{text|00|green}}{{text|00|blue}}''' to '''&HFF{{text|FF|red}}{{text|FF|green}}{{text|FF|blue}}''', always with full [[_ALPHA]].
* Returns [[LONG]] 32-bit hexadecimal values from '''&HFF{{Text|00|red}}{{Text|00|green}}{{Text|00|blue}}''' to '''&HFF{{Text|FF|red}}{{Text|FF|green}}{{Text|FF|blue}}''', always with full [[_ALPHA]].
* When [[LONG]] values are [[PUT]] to file, the ARGB values become BGRA. Use [[LEFT$]]([[MKL$]]({{Parameter|colorIndex~&}}), 3) to place 3 colors.
* When [[LONG]] values are [[PUT]] to file, the ARGB values become BGRA. Use [[LEFT$]]([[MKL$]]({{Parameter|colorIndex~&}}), 3) to place 3 colors.
* If the {{Parameter|imageHandle&}} is omitted the image is assumed to be the current [[_DEST|destination]] or [[SCREEN]] page.
* If the {{Parameter|imageHandle&}} is omitted the image is assumed to be the current [[_DEST|destination]] or [[SCREEN]] page.
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{{PageExamples}}
{{PageExamples}}
''Example:'' Converting the color port RGB intensity palette values 0 to 63 to 32 bit hexadecimal values.  
''Example:'' Converting the color port RGB intensity palette values 0 to 63 to 32 bit hexadecimal values.
{{CodeStart}}
{{CodeStart}}
{{Cl|SCREEN}} 12
{{Cl|SCREEN}} 12
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   {{Cl|COLOR}} attribute
   {{Cl|COLOR}} attribute
   {{Cl|PRINT}} "{{Cl|COLOR}}" + {{Cl|STR$}}({{Cl|_RGB}}(red, grn, blu)) + " = " + hex32$(attribute)  'closest attribute
   {{Cl|PRINT}} "{{Cl|COLOR}}" + {{Cl|STR$}}({{Cl|_RGB}}(red, grn, blu)) + " = " + hex32$(attribute)  'closest attribute
{{Cl|NEXT}}  
{{Cl|NEXT}}
{{CodeEnd}}
{{CodeEnd}}
{{OutputStart}}{{text|COLOR 1 <nowiki>=</nowiki> &HFF0000A8|#0000A8}}
{{OutputStart}}{{Text|COLOR 1 <nowiki>=</nowiki> &HFF0000A8|#0000A8}}
{{text|COLOR 2 <nowiki>=</nowiki> &HFF00A800|#00A800}}
{{Text|COLOR 2 <nowiki>=</nowiki> &HFF00A800|#00A800}}
{{text|COLOR 3 <nowiki>=</nowiki> &HFF00A8A8|#00A8A8}}
{{Text|COLOR 3 <nowiki>=</nowiki> &HFF00A8A8|#00A8A8}}
{{text|COLOR 4 <nowiki>=</nowiki> &HFFA80000|#A80000}}
{{Text|COLOR 4 <nowiki>=</nowiki> &HFFA80000|#A80000}}
{{text|COLOR 5 <nowiki>=</nowiki> &HFFA800A8|#A800A8}}
{{Text|COLOR 5 <nowiki>=</nowiki> &HFFA800A8|#A800A8}}
{{text|COLOR 6 <nowiki>=</nowiki> &HFFA85400|#A85400}}
{{Text|COLOR 6 <nowiki>=</nowiki> &HFFA85400|#A85400}}
{{text|COLOR 7 <nowiki>=</nowiki> &HFFA8A8A8|#A8A8A8}}
{{Text|COLOR 7 <nowiki>=</nowiki> &HFFA8A8A8|#A8A8A8}}
{{text|COLOR 8 <nowiki>=</nowiki> &HFF545454|#545454}}
{{Text|COLOR 8 <nowiki>=</nowiki> &HFF545454|#545454}}
{{text|COLOR 9 <nowiki>=</nowiki> &HFF5454FC|#5454FC}}
{{Text|COLOR 9 <nowiki>=</nowiki> &HFF5454FC|#5454FC}}
{{text|COLOR 10 <nowiki>=</nowiki> &HFF54FC54|#54FC54}}
{{Text|COLOR 10 <nowiki>=</nowiki> &HFF54FC54|#54FC54}}
{{text|COLOR 11 <nowiki>=</nowiki> &HFF54FCFC|#54FCFC}}
{{Text|COLOR 11 <nowiki>=</nowiki> &HFF54FCFC|#54FCFC}}
{{text|COLOR 12 <nowiki>=</nowiki> &HFFFC5454|#FC5454}}
{{Text|COLOR 12 <nowiki>=</nowiki> &HFFFC5454|#FC5454}}
{{text|COLOR 13 <nowiki>=</nowiki> &HFFFC54FC|#FC54FC}}
{{Text|COLOR 13 <nowiki>=</nowiki> &HFFFC54FC|#FC54FC}}
{{text|COLOR 14 <nowiki>=</nowiki> &HFFFCFC54|#FCFC54}}
{{Text|COLOR 14 <nowiki>=</nowiki> &HFFFCFC54|#FCFC54}}
{{text|COLOR 15 <nowiki>=</nowiki> &HFFFCFCFC|#FCFCFC}}
{{Text|COLOR 15 <nowiki>=</nowiki> &HFFFCFCFC|#FCFCFC}}
{{OutputEnd}}
{{OutputEnd}}
:''Note:'' This procedure also shows how the returns from [[_RGB]] and [[_RGB32]] differ in a non-32 bit screen mode.
:''Note:'' This procedure also shows how the returns from [[_RGB]] and [[_RGB32]] differ in a non-32 bit screen mode.
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* [[_LOADIMAGE]], [[_NEWIMAGE]]
* [[_LOADIMAGE]], [[_NEWIMAGE]]
* [[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 20:04, 5 January 2024

The _RGB function returns the closest palette attribute index (legacy SCREEN modes) OR the LONG 32-bit color value (32-bit screens).


Syntax

colorIndex~& = _RGB(red&, green&, blue&[, imageHandle&])


Description

  • The value returned is either the closest color attribute number or a 32-bit _UNSIGNED LONG color value.
  • Return variable types must be 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.
  • Intensity values outside the valid range are clipped.
  • Returns LONG 32-bit hexadecimal values from &HFF000000 to &HFFFFFFFF, always with full _ALPHA.
  • When LONG values are PUT to file, the ARGB values become BGRA. Use LEFT$(MKL$(colorIndex~&), 3) to place 3 colors.
  • If the imageHandle& is omitted the image is assumed to be the current destination or SCREEN page.
  • Colors returned are always opaque as the transparency value is always 255. Use _ALPHA or _CLEARCOLOR to change it.
  • NOTE: Default 32-bit backgrounds are clear black or _RGBA(0, 0, 0, 0). Use CLS to make the black opaque.


Examples

Example: Converting the color port RGB intensity palette values 0 to 63 to 32 bit hexadecimal values. 

SCREEN 12
DIM hex32$(15)
FOR attribute = 1 TO 15
  OUT &H3C7, attribute      'set color attribute to read
  red = INP(&H3C9) * 4      'multiply by 4 to convert intensity to 0 to 255 RGB values
  grn = INP(&H3C9) * 4
  blu = INP(&H3C9) * 4
  hex32$(attribute) = "&H" + HEX$(_RGB32(red, grn, blu))   'always returns the 32 bit value
  COLOR attribute
  PRINT "COLOR" + STR$(_RGB(red, grn, blu)) + " = " + hex32$(attribute)  'closest attribute
NEXT

COLOR 1 = &HFF0000A8
COLOR 2 = &HFF00A800
COLOR 3 = &HFF00A8A8
COLOR 4 = &HFFA80000
COLOR 5 = &HFFA800A8
COLOR 6 = &HFFA85400
COLOR 7 = &HFFA8A8A8
COLOR 8 = &HFF545454
COLOR 9 = &HFF5454FC
COLOR 10 = &HFF54FC54
COLOR 11 = &HFF54FCFC
COLOR 12 = &HFFFC5454
COLOR 13 = &HFFFC54FC
COLOR 14 = &HFFFCFC54
COLOR 15 = &HFFFCFCFC
Note: This procedure also shows how the returns from _RGB and _RGB32 differ in a non-32 bit screen mode.


See also


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