Getting back the Red, Green, and Blue

This is a discussion on Getting back the Red, Green, and Blue within the Game Programming forums, part of the General Programming Boards category; If I use the code: #define RGB32BIT(a, r, g, b) ((b) + (g << 8) + (r << 16) + ...

  1. #1
    Captain - Lover of the C
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    Getting back the Red, Green, and Blue

    If I use the code:
    #define RGB32BIT(a, r, g, b) ((b) + (g << 8) + (r << 16) + (a << 24)

    buffer[y * lpitch32 + x] = RGB32BIT(0, 0, 255, 0);

    How do I get back the alpha, red, green, and blue values? Something like?

    UCHAR b = buffer[y * lpitch32 + x];
    UCHAR g = buffer[y * lpitch32 + x] >> 8;
    UCHAR r = buffer[y * lpitch32 + x] >> 16;
    UCHAR a = buffer[y * lpitch32 + x] >> 24;

  2. #2
    Has a Masters in B.S.
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    what you got should work theoretically?
    Last edited by no-one; 05-13-2005 at 09:36 PM.
    ADVISORY: This users posts are rated CP-MA, for Mature Audiences only.

  3. #3
    Super Moderator VirtualAce's Avatar
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    BYTE Red=(PixelColor & 0xFF0000) >> 16;
    BYTE Green=(PixelColor & 0xFF00) >>8;
    BYTE Blue=(PixelColor & 0xFF);

  4. #4
    Captain - Lover of the C
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    Turns out I was right after all. But the reply above mine works too even though the '& 0xFF' is pointless if you shift it anyway.

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