[comp.sys.apple2] Blankit v0.1 bug. Not fault of SHRConvert

q4kx@vax5.cit.cornell.edu (Joel Sumner) (09/07/90)

I feel that I should clarify something that I may have misworded...

   I recently posted BLANKINIT v0.2 to comp.binaries.apple2.  In the beginning
of the post, I stated that it was a fix due to problems with SHRConvert.
In saying this, I did not intend to say that SHRConvert has a bug that
prevents BLANKINIT from working.  On the contrary, it was a 'bug' in 
BLANKINIT that messed up the screen when doing certain things in SHRConvert.
I will illustrate....
   Version 0.1 of Blankinit blanked the SHR Screen in the following way, it
saved all ColorTables, Replaced them with a table that turned all of the colors
to black, then turned the border color to black.  The problem with this
method was that a program (not necessarily SHRConvert) could go and change
the Color Tables while the screen was black and Blankinit would never be aware
of the change.  Thus, if you were converting a GIF, say, and the screen
was black when SHRConvert went to display the picture, it would change
Color Tables to the new colors of the picture.  So the screen would not be
'black' any more.  It would contain the converted picture (thus defeating
the screen blanker).  In addition, if the screen was unblanked by moving
the mouse or whatever, the previous Color Tables were restored thus giving
the converted picture some funny colors.  The only way around this was to
hit OA-F (full screen) and view the picture again.
   In this new version (0.2), the method I use to blank the screen has
been changed so that this problem cannot happen.  I apologize for any
confusion that my previous post may have caused.  

BTW, if you do use BlankInit, please tell me.  I just like to know if
anybody is using the stuff that I make.  (That goes for KeyCaps too)
-- 
Joel Sumner                     GENIE:JOEL.SUMNER     These opinions are 
q4kx@cornella.ccs.cornell.edu   q4kx@cornella         warranted for 90 days or
q4kx@vax5.cit.cornell.edu       q4kx@crnlvax5         60,000 miles.  Whichever
....................................................  comes first.
Never test for an error condition that you can't handle.