PRINTER Device Causes Error

Name: David Fanning	
E-mail Address: david@dfanning.com
IDL version: 6.0
Platform and OS: Windows 2000, Windows XP

Description of Behavior: 

Loading a color table (or color) with the TVLCT command while in
the PRINTER device causes this error:

   % TVLCT: Error creating device colortable.

Oddly, the test program does not cause an error the FIRST time
it is run in a new IDL session, only on subsequent times!!

   IDL> .COMPILE "C:\IDL\David\test.pro"
   % Compiled module: TEST.
   IDL> test
   IDL> test
   % TVLCT: Error creating device colortable.
   % Execution halted at: TEST                4 C:\IDL\David\test.pro

The problem appears to be confined to the Windows platform only.

Example Code:

  PRO Test
     thisDevice = !D.Name
     Set_Plot, 'PRINTER'
     TVLCT, 255, 255, 0, 200
     Set_Plot, thisDevice
  END

Know Workarounds or Fixes: 

None currently known, except to not load color tables while in the
printer device. In my program HISTOIMAGE, I have worked around the 
problem by identifying these three lines in the code:

   axisColor = GetColor(axisColorName, !D.Table_Size-2)
   dataColor = GetColor(datacolorName, !D.Table_Size-3)
   backColor = GetColor(backColorName, !D.Table_Size-4)

And replacing them with this:

IF !D.NAME NE 'PRINTER' THEN BEGIN
   axisColor = GetColor(axisColorName, !D.Table_Size-2)
   dataColor = GetColor(datacolorName, !D.Table_Size-3)
   backColor = GetColor(backColorName, !D.Table_Size-4)
ENDIF ELSE BEGIN
   Set_Plot, 'Z', /Copy
   axisColor = GetColor(axisColorName, !D.Table_Size-2)
   dataColor = GetColor(datacolorName, !D.Table_Size-3)
   backColor = GetColor(backColorName, !D.Table_Size-4)
   Set_Plot, 'PRINTER', /Copy
ENDELSE

RSI Technical Support Response: 

It seems that this is logged in the system as a defect.  Interestingly, you
are the first customer to report the issue.

I have associated you with CR 19330. [Your test program] 
fails, at least for me, in IDL 5.5, 5.6, and 6.0.  If you 
have any of the older versions around could you let me know 
if you are seeing the same behaviour? [I do, now that you
mention it!]

As always, I highly recommend that you encourage customers who are seeing
the same issue to contact us.  Our development group is definitely
influenced by the number of customers associated with a CR.