From: Bogdan Costescu (Bogdan.Costescu_at_IWR.Uni-Heidelberg.De)
Date: Thu Mar 09 2000 - 08:00:27 CST

On Wed, 8 Mar 2000, John Stone wrote:

> We weren't able to provide any help on this because we don't have
> access any O2's that can do stereo at all.

Sorry for being a little acid, I would have expected at least this
statement from the beginning and maybe some kind of dialog
try-this-and-tell-me-if-it-works...

> So you're running in 12-bit color???
> What does xdpyinfo tell you about your screen?

With a simple code from OpenGL documentation, I'm able to get 4 bits/color
and 5 bits/color for both 16 and 24 depth, but nothing (tried 1,2,4,5,8
as bits/color) for depth 32. However, I only tried 4 bits/color adn
depth 16 with VMD; if is good to know how the other modes are behaving,
I can try them too... At the end of the message you can find the ouput
from xdpyinfo.

> If you have a machine that will support both 24-bit color without stereo,
> or 12-bit color WITH stereo, which mode would you want VMD to "prefer"???
> Presently, there is no mechanism for VMD to know which of those two options
> the user would prefer. I can certainly modify VMD to choose all
> stereo-capable modes as being preferred to non-stereo modes, but this may
> not be what the majority of users want. Comments anyone?

An automatic mechanism will surely upset somebody. I would suggest a
config option (better) or a command-line option (worse) to force
video mode. If I get poor video because the automatic mechanism is also
looking for stereo, I can say "No more stereo" and get better video; at
this point, if the user chooses a true stereo mode from the Display form,
an error message should be displayed. If, on the other hand, I want
stereo by all means (like I do), I can force it to pick the best video
mode with stereo support, but I know that the eventual poorer video
quality is because I forced it.
Of course, all of the above should be clearly stated in the docs and
maybe a short message at the beginning telling which mode is chosen
(instead of "Stereo in a window is NOT supported.").

xdypinfo output:

name of display: :0.0
version number: 11.0
vendor string: Silicon Graphics
vendor release number: 6300
maximum request size: 262140 bytes
motion buffer size: 0
bitmap unit, bit order, padding: 32, MSBFirst, 32
image byte order: MSBFirst
number of supported pixmap formats: 5
supported pixmap formats:
    depth 1, bits_per_pixel 1, scanline_pad 32
    depth 8, bits_per_pixel 8, scanline_pad 32
    depth 12, bits_per_pixel 16, scanline_pad 32
    depth 15, bits_per_pixel 16, scanline_pad 32
    depth 24, bits_per_pixel 32, scanline_pad 32
keycode range: minimum 15, maximum 149
focus: window 0x4c00004, revert to PointerRoot
number of extensions: 28
    Adobe-DPS-Extension
    DCShare
    DEC-XTRAP
    DOUBLE-BUFFER
    DPSExtension
    Extended-Visual-Information
    GLX
    LBX
    MIT-SHM
    MIT-SUNDRY-NONSTANDARD
    Multi-Buffering
    READDISPLAY
    RECORD
    ReadDisplay
    SCREEN-SAVER
    SGI-NewMultibuffering
    SGI-SCREEN-CAPTURE
    SGI-SUNDRY-NONSTANDARD
    SGI-VIDEO-CONTROL
    SGIFullScreenStereo
    SHAPE
    SYNC
    XC-APPGROUP
    XC-MISC
    XInputExtension
    XKEYBOARD
    XTEST
    XVideo
default screen number: 0
number of screens: 1

screen #0:
  dimensions: 1280x1024 pixels (350x280 millimeters)
  resolution: 93x93 dots per inch
  depths (5): 1, 8, 12, 15, 24
  root window id: 0x40
  depth of root window: 8 planes
  number of colormaps: minimum 1, maximum 11
  default colormap: 0x3d
  default number of colormap cells: 256
  preallocated pixels: black 0, white 7
  options: backing-store NO, save-unders NO
  largest cursor: 32x32
  current input event mask: 0x72003c
    ButtonPressMask ButtonReleaseMask EnterWindowMask
    LeaveWindowMask StructureNotifyMask SubstructureRedirectMask
    FocusChangeMask PropertyChangeMask
  number of visuals: 29
  default visual id: 0x20
  visual:
    visual id: 0x20
    class: PseudoColor
    depth: 8 planes
    available colormap entries: 256
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x21
    class: PseudoColor
    depth: 8 planes
    available colormap entries: 256
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x22
    class: StaticColor
    depth: 8 planes
    available colormap entries: 256
    red, green, blue masks: 0xe0, 0x1c, 0x3
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x23
    class: TrueColor
    depth: 8 planes
    available colormap entries: 8 per subfield
    red, green, blue masks: 0xe0, 0x1c, 0x3
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x24
    class: TrueColor
    depth: 8 planes
    available colormap entries: 8 per subfield
    red, green, blue masks: 0xe0, 0x1c, 0x3
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x25
    class: PseudoColor
    depth: 8 planes
    available colormap entries: 256
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x26
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x27
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x28
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x29
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2a
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2b
    class: PseudoColor
    depth: 12 planes
    available colormap entries: 4096
    red, green, blue masks: 0x0, 0x0, 0x0
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2c
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2d
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2e
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x2f
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x30
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x31
    class: TrueColor
    depth: 15 planes
    available colormap entries: 32 per subfield
    red, green, blue masks: 0x7c00, 0x3e0, 0x1f
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x32
    class: TrueColor
    depth: 24 planes
    available colormap entries: 256 per subfield
    red, green, blue masks: 0xff, 0xff00, 0xff0000
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x33
    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: 0x34
    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: 0x35
    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: 0x36
    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: 0x37
    class: TrueColor
    depth: 24 planes
    available colormap entries: 256 per subfield
    red, green, blue masks: 0xff, 0xff00, 0xff0000
    significant bits in color specification: 8 bits
  visual:
    visual id: 0x38
    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: 0x39
    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: 0x3a
    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: 0x3b
    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: 0x3c
    class: DirectColor
    depth: 24 planes
    available colormap entries: 256 per subfield
    red, green, blue masks: 0xff0000, 0xff00, 0xff
    significant bits in color specification: 8 bits

Bogdan Costescu

IWR - Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen
Universitaet Heidelberg, INF 368, D-69120 Heidelberg, GERMANY
Telephone: +49 6221 54 8869, Telefax: +49 6221 54 8868
E-mail: Bogdan.Costescu_at_IWR.Uni-Heidelberg.De