DirectColor-visual?

[Harold L Hunt II]

Francisco,

Do you know what a DirectColor visual is?

Do you know why you would need a DirectColor visual?

Do you know of any Windows-based graphics cards that actually support 
DirectColor?


My understanding of DirectColor is that it allows you to specify the 
range of colors that will be used in a mode that is similar to 
TrueColor... however, I don't know of a single Windows graphics card 
that allows you to do that.  I don't know of any program that utilizes 
such a visual either.  As such, there is no support for DirectColor in 
Cygwin/XFree86.  I don't expect that there will ever be DirectColor 
support in Cygwin/XFree86 unless someone can explain to me that I am way 
wrong.

DirectColor seems like a lot of things in X: it was thought to be REALLY 
useful when X was designed, but it turned out to be anything but useful. 
  I read about those things once, then I ignore them after that.

So, anyone else know what DirectColor is?

Harold

Francisco Rojas wrote:
> I am running the lastest cygwin and xfree86.
> In 24 bit mode, I only get the TrueColor Visual.
> What I do I need to do to get a DirectColor Visual
>  listed using xdpyinfo ?
> 
> Currently, I am running a NVIDIA Gforce2 400?
> If I need to change videocards what are the recommended cards?
> I have not seen anything in the documentation or mailing lists.
> 
> 
> 
> 
> $ xdpyinfo
> name of display:    :0.0
> version number:    11.0
> vendor string:    The XFree86 Project, Inc
> vendor release number:    40200000
> XFree86 version: 4.2.0
> maximum request size:  4194300 bytes
> motion buffer size:  256
> bitmap unit, bit order, padding:    32, LSBFirst, 32
> image byte order:    LSBFirst
> number of supported pixmap formats:    7
> supported pixmap formats:
>     depth 1, bits_per_pixel 1, scanline_pad 32
>     depth 4, bits_per_pixel 8, scanline_pad 32
>     depth 8, bits_per_pixel 8, scanline_pad 32
>     depth 15, bits_per_pixel 16, scanline_pad 32
>     depth 16, bits_per_pixel 16, scanline_pad 32
>     depth 24, bits_per_pixel 32, scanline_pad 32
>     depth 32, bits_per_pixel 32, scanline_pad 32
> keycode range:    minimum 8, maximum 255
> focus:  window 0x400002, revert to PointerRoot
> number of extensions:    21
>     BIG-REQUESTS
>     DEC-XTRAP
>     DOUBLE-BUFFER
>     Extended-Visual-Information
>     FontCache
>     GLX
>     LBX
>     MIT-SUNDRY-NONSTANDARD
>     RECORD
>     RENDER
>     SECURITY
>     SGI-GLX
>     SHAPE
>     SYNC
>     TOG-CUP
>     XC-APPGROUP
>     XC-MISC
>     XFree86-Bigfont
>     XKEYBOARD
>     XTEST
>     XVideo
> default screen number:    0
> number of screens:    1
> 
> 
> screen #0:
>   dimensions:    1274x961 pixels (431x325 millimeters)
>   resolution:    75x75 dots per inch
>   depths (7):    24, 1, 4, 8, 15, 16, 32
>   root window id:    0x36
>   depth of root window:    24 planes
>   number of colormaps:    minimum 1, maximum 1
>   default colormap:    0x20
>   default number of colormap cells:    256
>   preallocated pixels:    black 0, white 16777215
>   options:    backing-store NO, save-unders NO
>   largest cursor:    1274x961
>   current input event mask:    0xd0001f
>     KeyPressMask             KeyReleaseMask           ButtonPressMask
>     ButtonReleaseMask        EnterWindowMask
> SubstructureRedirectMask
>     PropertyChangeMask       ColormapChangeMask
>   number of visuals:    2
>   default visual id:  0x22
>   visual:
>     visual id:    0x22
>     class:    TrueColor
>     depth:    24 planes
>     available colormap entries:    256 per subfield
>     red, green, blue masks:    0xff0000, 0xff00, 0xff
>     significant bits in color specification:    8 bits
>   visual:
>     visual id:    0x23
>     class:    TrueColor
>     depth:    24 planes
>     available colormap entries:    256 per subfield
>     red, green, blue masks:    0xff0000, 0xff00, 0xff
>     significant bits in color specification:    8 bits
> 
> 
> 
> Francisco Rojas
> Electrical and Computer Engineering Department
> University of Arizona, Tucson, Arizona
> OFFICE: ECE 408, 520.621.4554
> FAX   :          520.621.8076
> ----
>