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  • Adam Jackson's avatar
    EDID: Hack for 1366x768 in standard timing descriptors · 20ac3140
    Adam Jackson authored
    All you get for standard timing descriptors is horizontal size in
    multiples of 8 pixels (which means you can't say 1366) and height in
    terms of aspect ratio (which means you can't say 768).  You'd like to
    just fuzzy-match this by walking the DMT list for sufficiently close
    modes, but you can't because DMT is useless and only defines a 1360x768
    mode, because it's _also_ specified in terms of character cells despite
    providing pixel exact timings.  Neither can you use CVT or GTF to
    generate the timings, because they _also_ believe that modes have to be
    a multiple of 8 pixels.
    
    You'd also hope you could find a timing definition for this in CEA, but
    you can't because CEA only defines transmission formats that actually
    exist.  So there's 480p, 720p, and 1080p, but no 768p.  And why would
    there be, after all, the encoded signal is never 768p so obviously no
    one would ever make a display in that format.
    
    So instead, make a CVT mode since that's likely to be handled well by
    just about everything, smash the horizontal active down by 2, and shift
    the sync pulse by 1.  Underscanning the hard way.
    
    Pass the suicide.
    20ac3140