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Old 08-28-06, 05:27 PM   #2
NVIDIA Corporation
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Join Date: Mar 2005
Posts: 2,487
Default Re: PseudoColor overlay bits

Hi begal,

I assume you're talking about visuals that look like this (from xdpyinfo):
    visual id:    0x70
    class:    PseudoColor
    depth:    8 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0x0, 0x0, 0x0
    significant bits in color specification:    5 bits
This means that the visual has 8 planes, for a total of 256 colormap entries. Each colormap entry has a depth of 15 bits (5 bits per channel) for a total of 32,768 colors per colormap entry. The reason it's 5 bits per channel and not 8 is because the overlay hardware only supports depth 15.
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