Difference between revisions of "RED"

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(Redirected page to Color Components)
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#REDIRECT [[Color Components]]
The [[_RED]] function returns the palette index or the red component intensity of a 32-bit image color.
:: redintensity& = '''_RED('''{{Parameter|rgbaColorIndex&}}[, {{Parameter|imageHandle&}}]''')'''
* {{Parameter|rgbaColorIndex&}} is the ''RGBA'' color value or palette index of the color to retrieve the red component intensity from.
* The [[LONG]] intensity value returned ranges from 0 (no intensity, not present) to 255 (full intensity).
* If {{Parameter|imageHandle&}} specifies a 32-bit color image, {{Parameter|rgbaColorIndex&}} is interpreted as a 32-bit ''RGBA'' color value.
* If {{Parameter|imageHandle&}} specifies an image that uses a palette, {{Parameter|rgbaColorIndex&}} is interpreted as a palette index.
* If {{Parameter|imageHandle&}} is not specified, it is assumed to be the current write page.
* If {{Parameter|imageHandle&}} is an invalid handle, an [[ERROR Codes|invalid handle]] error occurs.
* If {{Parameter|rgbaColorIndex&}} is outside the range of valid indexes for a given image mode, an [[ERROR Codes|illegal function call]] error occurs.
* Uses index parameters passed by the {{KW|_RGB}}, {{KW|_RGBA}}, {{KW|_RGB32}} or {{KW|_RGBA32}} funtions.
* An image handle is optional.
''See Example:''
* [[POINT]]
* [[_GREEN]], [[_BLUE]]
* [[_RGB]], [[RGB32]]

Revision as of 03:42, 25 July 2017

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