Help with Problems
- My SGI machine has plenty of memory but it does not seem be available to Stradx.
- Use gmemusage to see which processes are using all the memory.
There is a known memory leak in the objectserver in Irix 6.2, so you may need to
kill it and restart it should you find that it is using an absurd amount of memory.
- The position sensor does not respond.
- First of all, make sure you are using a correctly wired serial
cable between the position sensor and the computer. For the Bird sensor, the
cable should connect pins 2, 3 and 5 only, as described in the
manufacturer's documentation.The Fastrak takes a long time to boot up,
so if you try and talk to
it too quickly after it is turned on you will break the link
and it will be necessary to cycle the Fastrak's power to reestablish it.
If you try to use the sensor with the wrong serial port speed you will
break communications in a similar way. In all such cases it is best to
reboot the sensor and leave it for a few minutes to initialise before
trying to poll it with Stradx.
When you select a new device in the `Edit setup'
panel, Stradx polls the device and tries to work out if it is talking
to a Bird, Fastrak or Polaris. In order to retry a device address, you should change it to /dev/null and then change it back to the
correct address. On SGI systems,
if you have forgotten to disable the getty process on the
tty line you are using for the position sensor, then serial communication
with the sensor will not work. This is solved by appropriate editing of
the /etc/inittab file.
- The `Preview' window is blank on my SGI system.
- It is possible for the video card to get into a confused state. Once
it is in this state the Stradx controls are sometimes inadequate to fix it.
If you run the vcp program you should be able to get it to
work again. Once you are able to display good images using
vcp, Stradx should also work. You do not have to shut
down Stradx while running vcp.
- Zero recording frame rate.
- If you are not recording position information then this may be
a similar problem to that which causes a blank `Preview' window (SGI
systems only). When position information is being recorded then the
most likely cause is that communication with the position sensing
device has broken down. The best cure for this is to cycle the power
on the position sensing device, give it plenty of time to
reinitialise, and then try probing it again from Stradx by selecting
the device in the `Edit setup' panel.
See the section above that describes how to fix a position sensor that
does not respond.
- Warning message about low quality display.
- Stradx attempts to provide the highest quality graphics
display by asking the X server for suitable high quality visuals. If
these visuals are not available (because your graphics card does not
support them), then Stradx still runs but warns you that the graphics
quality may be poor.
- Warning message about no model data available (wireframe.data).
- If you wish to use Stradx's body registration facilities, make sure
the file wireframe.data is installed in the same directory as
the Stradx executable: you will also need to specify the full path of
the Stradx executable when you run Stradx (ie. do not rely on symbolic
links or your shell's search path), otherwise Stradx will not be able
to find the wireframe.data file.
- Warning message about maxlkmem restricting the size of the
recording buffer (SGI version only).
- Stradx needs to reserve a large amount of memory for use as a
recording buffer: it expects to be able to lock-up about three
quarters of the total machine memory. For this to be possible, you may
need to tune the operating system's kernel to raise the `maxlkmem'
limit: this kernel parameter dictates how much memory a user process
is allowed to lock. This is something your System Administrator needs
to do: click here for further instructions.
- Warning message "XtRemoveGrab asked to remove a widget not on
the list" (Linux version only).
- This is a known problem with old versions of the Lesstif
widget library: either ignore the warning, or upgrade to the latest
- Numerical values are not displayed above sliders while they are dragged
(Linux version only).
- You are running an old version of Lesstif, with a slightly
buggy libXm.so.2. Upgrade to the latest version and this problem will
- Warning message "QUERYCAP ioctl in construct_v4l2_buffer
failed: Invalid argument" (Linux version only).
- You may be running the wrong version of Stradx for your
`Video for Linux 2' installation. Try running the other
version. Alternatively, you may be running `Video for Linux' instead
of `Video for Linux 2'.
- Rendering errors with accelerated graphics cards (Linux version only).
- Several XFree86 and X.org distributions shipped with buggy
direct rendering drivers. Consequently, you
might see rendering artefacts in Stradx's various graphics
windows. You can either tolerate these errors, or disable direct
rendering by running Stradx as follows: LIBGL_ALWAYS_INDIRECT=1
- Segmentation faults when opening/closing graphics windows (Linux
- Some direct rendering drivers no longer seem to
cope well with mutliple graphics contexts (they used to work fine). If
Stradx crashes with a segmentation fault when you open or close a
graphics window, disable direct rendering by running Stradx as
follows: LIBGL_ALWAYS_INDIRECT=1 stradx &