rdesktop color depth

[Avinoam]

hello

i implemented the rdesktop system on my network, the problem is that i can only work with 8bpp color depth ( 256 colors)when working with Win2K TS or WinXP .
how can i indrease the color depth ?

[Dorothee Singer]

have you tried the -C option?
for me it works fine.
yours
doro

[Avinoam]

can you write me your comman line with the -C option

thanks Avinoam

[Dorothee Singer · Accepted solution]

sorry, that i'm so late in answering - didn't get a notification from hp.

here is my complete command:
./rdesktop -g 1268x985 -C -u singer 192.168.2.211

sorry again for being so late.
yours
doro

[Avinoam]

hey doro

i still have this problem and i wonder if you solve it ..
i use redhat-9 as the rdesktop client , if i simply run ./rdeskrop 192.168.1.3 i get the windows screen but i only have 256 ( color )
and when i use the -C switch ( like the command you wrote me ) i get the following error :

X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 78 (X_CreateColormap)
Serial number of failed request: 23
Current serial number in output stream: 32

if you solve it i will be happy to hear how, if you havent sen that i will be more the happy to know which linux and which version of rdesktop u used ?

thanks for your help !!

Avinoam

[Alex Glennie]

I suspect the rdesktop utility has been written on a native Xserver which by default will only expect to have access to 256 colors.

The Bad mismatch error suggests rdesktop is trying to use it's own colormap which is different/conflicting to the default visual on your local display. ie without changing rdesktop code I'm not sure this maybe possible.

Breif discussion :

The number of colors that are available on a display is determined by
both the graphics card and the Xserver, and by default can not exceed
256. The following is a brief discussion of how colors are allocated.

Generally, X applications will use the default colormap, which, by
default, has 256 colormap slots available for color allocation
and is shared by all other clients that use the default colormap.

As you allocate unique colors, the map slots are marked "in use" and
after 256 unique colors are allocated (between all users using this
colormap) the colormap is full and no more colors can be allocated.

The map slots are shared (by default) and users requesting colors that
are already allocated will use the already allocated map slots (however,
users can attempt to allocate private color cells in the color map and
these color cells will not be shared with other users, even if the
colors are the same as already allocated colors).

Applications that are color intensive sometimes create their own
colormap (this is what netscape does when invoked with the install
option) and will have all 256 colormap slots available to them. Their
is no practical limit to the number of private colormaps that can be
created; however, depending on the graphics hardware, their is a limit
to the number of hardware colormaps that can be installed at any given
time.

The limit on hardware colormaps will not prevent a client from running
or allocating its own colormap (but, it can give the technicolor effect,
or flickering. The window manager will install the appropriate colormap
when a client with a private colormap receives the input focus.

Finally, remember that the number of colors available in the Xserver's
colormap is 256 by default. If the graphics hardware is capable, this
can be changed by telling the Xserver to use a different visual; for
example a 24-bit visual would allow over 16 million colors. However,
many applications expect that they will be running in an 8-bit visual
and may not function properly if the default visual is set to 24-bit.
Therefore, in a normal Vue/CDE environment, the Xserver runs in an 8-bit
visual and is limited to 256 colors in the colormap.

[Dorothee Singer]

hi,
i don't know, if you need it yet, but now rdesktop 1.3.1 is available and it works fine with 16bit.
i missunderstood you first time - i used the 256colours the last months, too. but now, since i compiled 1.3.1, it works really fine with lots of colours and my users are more than happy ;-)
other bugs are fixed, too - e.g. the copy/paste function between unix/windows.

anyway - perhaps you know all this or do not receive answers for this post any longer.
but i thought, i would better say; just to be sure.

best wishes,
doro