$COLOR

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$COLOR is a metacommand that adds named color constants into a program, which then can be used instead of hardcoded literal color values.


Syntax

$COLOR:{0|32}


Parameters

  • The one and only parameter is a literal number designating either to include SCREEN 0 based color indexes, or full _RGB32 color values with full (opaque) alpha.


Description

  • $COLOR:0 adds constants for the colors 0-15 available in SCREEN 0, these do also match for the first 16 colors on 8-Bit (256 colors) graphic screens as long as they are not changed using PALETTE or _PALETTECOLOR. For the actual constant names see $COLOR:0 Name Table.
  • $COLOR:32 adds constants for full 32-Bit color values as used on 32-Bit screens created via _NEWIMAGE, similar to HTML color names. For the actual constant names see $COLOR:32 Name Table.
  • Prior to QB64-PE v0.5.0, $COLOR was not compatible with $NOPREFIX.
  • Since QB64-PE v0.5.0, $COLOR can now be used with $NOPREFIX, with a few notable differences to three conflicting colors -- Red, Green, Blue.
Red would conflict with _RED, Green would conflict with _GREEN, and Blue would conflict with _BLUE, once the underscore was removed from those commands with $NOPREFIX.
To prevent these conflicts, the COLOR values have had NP_ prepended to the front of them, to distinguish them from the non-prefixed command names. All other color names remain the same, with only the three colors in conflict having to use NP_ (for No Prefix) in front of them.
Note that $NOPREFIX was deprecated in QB64-PE v4.0.0 and so also the NP_ color names are gone.


Examples

Example 1
Adding named color constants for SCREEN 0.
$COLOR:0

COLOR BrightWhite, Red
PRINT "Bright white on red."
Bright white on red.

Example 2
Adding named color constants for 32-bit modes.
SCREEN _NEWIMAGE(640, 400, 32)
$COLOR:32

COLOR CrayolaGold, DarkCyan
PRINT "CrayolaGold on DarkCyan."
CrayolaGold on DarkCyan.

Example 3
Adding named color constants for 32-bit modes (with $NOPREFIX in effect).
$NOPREFIX

SCREEN NEWIMAGE(640, 400, 32)
$COLOR:32

COLOR NP_Red, White 'notice the NP_ in front of Red?
'This is to distinguish the color from the command with $NOPREFIX.
PRINT "Red on White."
Red on White.


See also



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