Computes a valid color value for hi/truecolor modes
Syntax
Usage
result = RGB(red, green, blue)
Parameters
red
red color component value
green
green color component value
blue
blue color component value
Return Value
The combined color.
Description
red,
green and
blue are components ranging
0..
255.
The
RGB function can be used to compute a valid color value for use while in hi/truecolor modes. It returns an unsigned integer in the format
&hAARRGGBB, where
RR,
GG and
BB equal the values passed to this function, in hexadecimal format.
AA is the implicit alpha value and is automatically set to
&hFF (opaque).
It is possible to retrieve the red, green, blue and alpha values from a color value, by using a combination of
And and
Shr. The second example below shows how to
#define and use macros to do this.
Note for Windows API programmers: The macro named
RGB in the Windows references has been renamed
BGR in the FB headers for Windows to avoid collisions.
Example
See
Put (Graphics) example in addition.
ScreenRes 640,480,32 '32 bit color
Line(0,0)-(319,479), RGB(255,0,0) 'draws a bright red box on the left side of the window
Line(639,0)-(320,479), RGB(0,0,255) 'draws a bright blue box on the right side of the window
Sleep 'wait before exiting
'' setting and retrieving Red, Green, Blue and Alpha values
#define RGBA_R( c ) ( CUInt( c ) Shr 16 And 255 )
#define RGBA_G( c ) ( CUInt( c ) Shr 8 And 255 )
#define RGBA_B( c ) ( CUInt( c ) And 255 )
#define RGBA_A( c ) ( CUInt( c ) Shr 24 )
Dim As UInteger r, g, b, a
Dim As UInteger col = RGB(128, 192, 64)
Print Using "Color: _&H\ \"; Hex(col, 8)
r = RGBA_R( col )
g = RGBA_G( col )
b = RGBA_B( col )
a = RGBA_A( col )
Print
Print Using "Red: _&H\\ = ###"; Hex(r, 2); r
Print Using "Green: _&H\\ = ###"; Hex(g, 2); g
Print Using "Blue: _&H\\ = ###"; Hex(b, 2); b
Print Using "Alpha: _&H\\ = ###"; Hex(a, 2); a
Dialect Differences
Differences from QB
See also