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 Lesstif release.

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 go away.

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 stradx &

Segmentation faults when opening/closing graphics windows (Linux version only).

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 &