visuals of different depths on same screen?

[Corné Beerse]

Jeff Boerio wrote:

> I'm trying to configure Xvnc so that it will accept multiple color
> depths on the same screen.  We have two applications, one which is
> required to run in 8-bit pseudocolor mode, and another which requires a
> 24-bit color depth.

For what I know of `Xvnc` is that it implements a basic X11 server with roughly 
not options included. Hence, multiple color depths is most likely not available.

However, if you use a vnc-variant that hooks into the console and sends that 
info, then it relies on the effective Xserver (XFree86 such) for the X11 options 
and hence all should somehow work.

Hence, for you: either use one of the vnc-variants that give access to the 
effective X11 server on the console (like vnc.so that comes with the new 
version). Or you should setup 2 dedicated vnc-servers for your applications.

Somewhere in the middle, if your 24-bit-color-hongry tool effectively only uses 
up to 150 or 200 colors, you should be able to use that on an 8-bit device with 
a pre-defined colormap. Then just give both tools their own set of 8-bit colors 
and use that in a vnc-session. I've seen this 24-bit-app-in-8-bit-device working 
on a Sunworkstation but I don't recal any details...


CBee

> 
> There are ways to tell the Xvnc server that you want to use multiple
> pixel color depths for a screen (specify "-pixdepths 8 24" on the
> command line), but I am not able to get multiple visuals to accept the
> 24-bit depth that is required.
> 
> If I have "Xvnc :1 -pixdepths 8 24 -depth 8 -cc 3", relevant information
> from xdpyinfo is as follows:
> ..
> number of supported pixmap formats:    3
> supported pixmap formats:
>     depth 1, bits_per_pixel 1, scanline_pad 32
>     depth 8, bits_per_pixel 8, scanline_pad 32
>     depth 24, bits_per_pixel 32, scanline_pad 32
> ..
> default screen number:    0
> number of screens:    1
> 
> screen #0:
>   dimensions:    1024x768 pixels (260x195 millimeters)
>   resolution:    100x100 dots per inch
>   depths (3):    1, 8, 24
> ..
>   number of visuals:    6
>   default visual id:  0x22
>   visual:
>     visual id:    0x22
>     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:    0x23
>     class:    GrayScale
>     depth:    8 planes
>     available colormap entries:    256
>     red, green, blue masks:    0x0, 0x0, 0x0
>     significant bits in color specification:    8 bits
>   visual:
>     visual id:    0x24
>     class:    StaticColor
>     depth:    8 planes
>     available colormap entries:    256
>     red, green, blue masks:    0x7, 0x38, 0xc0
>     significant bits in color specification:    8 bits
>   visual:
>     visual id:    0x25
>     class:    TrueColor
>     depth:    8 planes
>     available colormap entries:    8 per subfield
>     red, green, blue masks:    0x7, 0x38, 0xc0
>     significant bits in color specification:    8 bits
>   visual:
>     visual id:    0x26
>     class:    DirectColor
>     depth:    8 planes
>     available colormap entries:    8 per subfield
>     red, green, blue masks:    0x7, 0x38, 0xc0
>     significant bits in color specification:    8 bits
>   visual:
>     visual id:    0x27
>     class:    StaticGray
>     depth:    8 planes
>     available colormap entries:    256
>     red, green, blue masks:    0x0, 0x0, 0x0
>     significant bits in color specification:    8 bits
> 
> What I need to get to is a visual that has a class of PseudoColor, depth
> of 8, and 256 available colors at the same time there is another visual
> that is a TrueColor class, depth of 24 and the large colormap entry you
> would expect to have.
> 
> I have been able to get Xvnc to have multiple screens (Xvnc :1 -screen 0
> 800x600x8 -screen 1 800x600x24), each with its correct colormap, so
> there MUST be a way to have it all on the same screen.
> 
> Are there any X11 experts out there who can shed some light on how this
> might be achieved?
> 
>      - Jeff
> _______________________________________________
> VNC-List mailing list
> VNC-List "at" realvnc.com
> To remove yourself from the list visit:
> http://www.realvnc.com/mailman/listinfo/vnc-list