Digitizing Tablet Information for AutoCAD on IRIX


In this document, you'll find information about:


Digitizing Tablets:

The use of digitizing tablets with AutoCAD on IRIX is somewhat complicated. Fundamentally, there are two mechanisms by which AutoCAD can get access to any pointing device, that is:

In the first case, you configure IRIX to recognize the pointing device and configure AutoCAD to use the System Pointer (digitizer configuration menu item 'None'). This is how the system mouse is configured and used with AutoCAD. Of course, when using the System Pointer, you in effect have a 'mouse' and no access to AutoCAD's Tablet Menu facilities. In IRIX 6.x, the input manual page has more information on tablets.

In the second case, you must *not* configure IRIX to recognize the device and must also make sure the port the device is attached to is marked 'available'. Then, you are free to configure AutoCAD to make use of the external pointing device. I strongly recommend you connect your digitizing tablet to serial port #2 if at all possible. Serial port #1 is by default configured as a system terminal/console.


FAQ:

Here are some answers to frequently asked questions regarding AutoCAD and digitizers:

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Screen Area Mode:

IMPORTANT: You should *not* attempt to install the digitizer Screen Area (or MoleMode) drivers from the AutoCAD R13 CD on an IRIX 6.x system. The drivers on the AutoCAD R13 CD are for IRIX 5.x systems only!

Screen Area (a.k.a. Mole Mode in R12 days) is a mode that allows you to control the system pointer from either the system mouse or AutoCAD's digitizing tablet (if so configured). Without this feature, you'll find interacting with AutoCAD's dialog boxes and other system menus difficult with a tablet. When properly configured, Screen Area mode provides a seamless interaction with multiple windows from the tablet.

Notes:

  1. Screen area support only works when at least one AutoCAD session is active.
  2. Conversely, if you want to use another application that uses the tablet, you'll need to be sure and end your AutoCAD session before doing so to avoid device contention.
  3. The Screen Area drivers on the AutoCAD R13 CD are for IRIX 5.x systems.
  4. If you are using IRIX 6.x, you'll want to check this important information.
An updated IRIX5.3 version of the Screen Area drivers may be downloaded here.
* Now detects proper O/S version.
An updated IRIX6.x version of the Screen Area drivers may be downloaded here.
* Now supports 32 and 64 bit kernels, including both R8000 and R10000 CPUs.

One problem that can arise in installing the Screen Area drivers is that the system disk may have been mounted with the "Restrict set-uid executables" option enabled. If this is the case, you should consult Chapter 6 of the Personal System Administration Guide for information on disk mounting options. Some components of the Screen Area drivers require "set UID" permissions in order to allow non-root users to access the X server input stream to allow coordinate data from the AutoCAD tablet driver to drive the system cursor.

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X Windows and Input Focus:

The X Window System has a very flexible input system. It is based on the concept of 'Window or Keyboard Focus' whereby one (and only one) window on your screen has 'focus', meaning it is receiving keyboard and pointer events. The default means of determining which window has focus is 'implicit', meaning the window that has the cursor inside of its boundaries has focus. The window with focus need not be on top of the window hierarchy, only some small portion must be visible. This is very useful, for example, in a 'cut and paste' operation. You can select some text by dragging the cursor over it in one window and then quickly paste it into another just by moving the cursor over a visible option of the other window and pressing the paste (middle) mouse button.

However, as nice as this focus policy is, in some cases, it may be desirable to adopt a different policy. The 4D Window Manager (4Dwm) offers an 'explicit' keyboard focus policy with a number of options. In explicit mode, you change window focus by some explicit action, such as clicking in the window you wish to receive focus.

Note: This is almost identical to the window focus policy used in the Microsoft Windows graphical user environments.

When the focus policy is "explicit", four resources can be set to True to allow a window to receive keyboard focus automatically at specified times:

autoKeyFocus When the window with focus is iconified or unmapped (gives focus to the window that last had it)
deiconifyKeyFocus When the window is iconified
raiseKeyFocus When the window is raised to the top of the stack
startupKeyFocus When the window is mapped

Table: 4D Window Manager resource options.

Among these, the raiseKeyFocus behavior is interesting to use with AutoCAD, especially when you make heavy use of dialog box operations. In this manner, whenever a dialog box appears (i.e. it is raised to the top of the stack) it automatically receives keyboard focus. Along with this option, the autoKeyFocus is useful as after the dialog is closed, focus returns to the window that last had it, namely the AutoCAD window.

The focus policy must be done on a session-wide basis as it is the window manager (4Dwm in the case of SGI workstations) that enforces the policy. This means that all windows on your workstation display will behave in the same way. The way to change these settings is through the 4D Window Manager's applications defaults file, located at:

/usr/lib/X11/app-defaults/4DWm

The setting that can be changed are:

*keyboardFocusPolicy: pointer / explicit
*autoKeyFocus: false / true
*deiconifyKeyFocus: false / true
*raiseKeyFocus: false / true
*startupKeyFocus: false / true

Table: 4D Window Manager resource settings.

It is recommended that you make a backup copy of this resource file, before changing it. The window manager must be stopped and restarted for any changes made to take effect. This may be accomplished from the ToolChest->System->Restart_Window_Manager menu item.

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[Last updated: 18.JUL.2001]