Compiled by Mike Dickason [72711,3404]
August  3, 1992          Initial posting     Bugs 1-12
August 11, 1992          Second posting      Bugs 13-19
August 17, 1992          Third posting       Bugs 20-24

The following list of ACAD 12 bugs and corresponding work arounds
was compiled from a combination of problems I have personally
encountered and from messages posted on the ACAD forum of
Compuserve.  I am not an employee of AutoDesk, nor did I compile
this list to discredit AutoDesk.  Indeed, I am quite happy with
R12, but as with any program of this size and magnitude, there are
some bugs.

This is not an official nor a complete list of R12 bugs.  It is
meant to be used as an informative list to help other users who
might be encountering similar problems.  All of the problems on
this list have been reported to and acknowledged by ADESK.  If you
know of any bugs which are not included on this list, I would be
interested in hearing about them, solely for the purpose of keeping
the list up to date.  Unless noted otherwise, the bugs are present
in the North American version of ACAD R12.  

1.   If you run any command which accepts the new fence selection
     option to select items (like the trim command), any subsequent
     usage of the lisp function (ssget "f" (list p1 p2)) will
     generate a heap error and will either instantly reboot the
     computer or dump you out of the editor to the DOS prompt
     without saving your drawing.  No known workaround.

2.   Lantastic bug with DOS 5.0 and R12.  Unable to run ACAD across
     the network, or edit any drawing located on the network
     without generating sharing violation errors.  

     To solve the problem, download the file R12LAN.ZIP from the
     forum.  This patch allows AutoCAD to run on various  
     networks, including LANtastic, 3Com and DEC Pathworks, under
     DOS 4.0 and  5.0. See the README.DOC file included in the
     archive for specific instructions on how to use the patch.

3.   The Hitachi HDG driver shipping with R12 does not work with
     the Hitachi HDG 1111C and possibly earlier models.  Need to
     download the file DGPHIT.EXP from here on the forum.

4.   The display filters for color and linetype with the DDLMODES
     command in R12 don't recognize the ~ wildcard.  If you specify
     the color filter as W*, only those layers which have a color
     beginning with the letter 'w' are displayed, as expected.  But
     if you specify the wildcard as ~W*, all of the layers are
     displayed instead of only those which don't have a color
     beginning with the letter 'w'.  Same applies for linetype
     wildcards.  No know work around.

5.   The layer DEFPOINTS is supposed to be an unplottable layer,
     but in R12 it is showing up on plots, regardless of whether it
     is turned on or off.  No known work around.

6.   When Release 12 compiles a PFB PostScript font file into an
     SHX font file, it makes the font approximately 30% too small. 
     If you insert some text with a regular AutoCAD font (such as
     Simplex) with a height of 2.5", it is drawn 2.5" inches tall.
     If you insert text with a converted PostScript font with a
     height of 2.5", it is drawn 1.7" high.  No known work around.

7.   The path to the R12 drivers is stored within the ACAD.CFG
     file.  If you change rename the ACAD directory, or move it to
     a different location, then attempt to reconfigure ACAD using
     the "-R" switch, it will not find any drivers because it looks
     at the path stored in ACAD.CFG instead of the environment
     variable ACADDRV.  The only workaround is to delete the
     ACAD.CFG file and reconfigure ACAD.

8.   When plotting with R12, if you use a plot scale of 1/8=12, the
     plot dialogue box rounds the scale off to the nearest tenth
     and displays the plot scale as 0.13=12.  It also plots the
     drawing at that scale.  Use 1=96 to get a 1/8" plot scale.  

9.   When you try to plot a R10 drawing it works just fine if you
     bring up the drawing in the editor.  If you use the
     freeplotting feature by calling acad with a -P then it crashes
     with a EREAD error.  The only workaround is to plot from
     within the editor.

10.  The Calcomp plotter driver shipping with R12 produces erratic
     plots under various situations.  Download the updated driver
     PLPCC.EXP from here on the forum.

11.  The HP-GL2 plotter driver has a problem handling smart fills. 
     and will exhibit problems with filled areas such as plines
     with a width.  The only known work around is to use an HP-GL2
     driver written for R11.

12.  Here's a minor bug with R12's help command.  Run the help
     command, and select "Index" from the opening dialog box. 
     Double click on any item in the index list (I'll use 3D as the
     example) and the help screen for that item comes up as
     expected.  Now select "Index" again and the index dialog pops
     up with the selected item still highlighted.  Select "OK" to
     view the same item again and you get a prompt that says
     "Nothing selected." even though the item is still highlighted. 
     To get the item again, you have to physically select it
     instead of just selecting "OK".

13.  If you perform a PEDIT Join command on a polyline containing
     curve information, the resultant joined polyline is stripped 
     of all the curve information leaving you with a polyline made
     entirely of straight line segments.  No known workaround.

14.  With a closed polyline, if you perform the sequence PEDIT,
     Edit vertex, Break, the command will not only break out the
     segment between the specified vertices, but it also removes
     the "closing" segment of the polyline leaving you with two
     separate polylines if you attempt to break out an interior
     section.  No known workaround.

15.  There is a problem in the plot command when specifying MM as
     the plot units. If you change any of the default pen widths,
     each time you go into the pen parameters menu, the pen widths
     are multiplied by 25.4.  This eventually leads to a general
     protection fault and ACAD crashing.

     To show this, run the plot command, set the units to MM, then
     select Pen Assignments.  Start clicking on pen 1, and watch
     the width display in the bottom right corner.  Each time it
     increments by a factor of 25.4. Click on pen 1 twenty six
     times, then select OK, then immediately select Pen Assignments
     again.  You will get "FATAL ERROR: General protect exception"
     which immediately returns you to the DOS prompt without saving
     the drawing.

16.  When plotting units are set to MM, retrieving a pcp file
     results in the paper size being multiplied by 25.4, even if
     the pcp was stored with MM units.  No known work around.  When
     restoring plot defaults from a file, make sure to check the
     paper size before you plot.

17.  There is a problem with certain DIMVARS when DIMSCALE is not
     set to 1.  It affects all DIM variables with distance-type
     values, like DIMCEN, DIMTXT, DIMASZ, etc.  With these
     variables, if you are in the DIM command and you type in the
     variable name (like DIMCEN) and hit enter to take the default,
     the default value is divided by the value of DIMSCALE and the
     result becomes the new default.  You can avoid the problem for
     now by setting DIM vars outside the DIM command (like other
     system variables), or by retyping the default value rather
     than using ENTER to retain it.

18.  When using the new Shift to Add feature for building selection
     sets, the "Window" and "Crossing" selection options add to the
     current selection set instead of replacing it as documented. 
     No known work around.

19.  If you perform a Dview Twist on a drawing, then plot with a
     window, the coordinates of the window corners displayed in the
     new plot dialog box do not match the actual coordinates that
     were picked.  Regardless of what the plot window shows, the
     actual coordinates picked are used for generating the plot. 
     This appears to related to the variable "TARGET", which
     changes after a DVIEW, but never seems to be set back to its
     default value (i.e. start a new drawing, look at the value of
     TARGET, then do a Dview Twist 300, Dview Twist 0, and then
     look at TARGET again and it is different).  No known work
     around.


20.  There is a bug with variable width polylines and the commands
     PEDIT and Undo.  If you have a variable width polyline, then
     perform a Pedit on it and change the width to 0, then at the
     command prompt do an Undo which backs through the Pedit, the
     starting and ending widths of the first segment of the
     polyline will be applied to the entire polyline.  The
     following sequence demonstrates the problem:
  Command: PLINE
  From point: 0,0
  Current line-width is 0'-0"
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: W
  Starting width <0'-0">: 0
  Ending width <0'-0">: 3
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 0,0
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: W
  Starting width <0'-3">: 0
  Ending width <0'-0">: 0
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 10,10
  Arc/Close/Halfwidth/Length/Undo/Width/<Endpoint of line>: 20,10
 
  Command: PEDIT
  Select polyline: Last
  Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo/eXit <X>: W
  Enter new width for all segments: 0
  Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo/eXit <X>: X
 
  Command: U

     No known workaround.

21.  A fatal bug with the R12 menu command.  With FILEDIA=0, run
     the Menu command and type in the name of a non-existant menu. 
     ACAD will report that it can't open the file and display the
     search path used.  It then prompts "Enter another menu file
     name (or RETURN for none):".  If you hit the return button on
     the digitizer instead of the keyboard, you will get a       
          "FATAL ERROR: Null pointer referenced"
          "Do you want to save your changes?  <Y> "

     The workaround is to use the keyboard for hitting the Enter
     key.

22.  There is a problem with the pen parameters dialog box in the
     R12 plot command.  The program is handling pens in groups of
     10, ie. 1-10, 11-20, 21-20, etc.  If you make a change to any
     of the pen parameters for pens 11-256, the corresponding pen
     in group 1-10 is changed as well.  For example, change pen 11
     to have a width of 1.0, then scroll up and look at pen 1.  Its
     width will have changed to 1.0 as well.  It also works the
     other way.  Change pen 1 and pen 11 changes, and pen 21
     changes, etc.  No known workaround.

23.  R12 has a problem with Wblocks and file locking when using
     relative paths to specify the drawing name.  With file locking
     turned on, if I open a file with a relative path, then attemp
     to Wblock the drawing back to itself using the same relative
     path, ACAD reports the following error message:

         Unable to lock file .\MIKE
         File write locked by USER1
         at 10:00 on 08/13/1992

          The command sequence to show this...

               Command:     OPEN
               File name:   .\MIKE
               Command:     WBLOCK
               File name:   .\MIKE

     R11 didn't exhibit this problem.  The only way to make it work
     in R12 is to type out the full path for the Wblock name, which
     is a pain when you have long paths for the file directories. 
     
     The same problem occurs if you open a new drawing with a
     relative path then attemp to save it using the SAVE command.

24.  Load a drawing with enough blocks to enable the sliders in a
     list box.  Call DDINSERT and pick Block to get a listing of
     the blocks.  Change the Pattern specification to anything that
     will retain the sliders (or just delete the "*" and enter it
     again).  Then slide the list to the bottom and release - it
     goes back to the top of the list.  It happens whenever you
     change the Pattern specification.  However, it will work
     correctly if you do it a second time - only happens the first
     time after changing the Pattern specification.
