PRODUCT  :  Borland C++                           NUMBER  :  1025
  VERSION  :  3.1
       OS  :  DOS
     DATE  :  October 23, 1992                         PAGE  :  1/2

    TITLE  :  Optimizing Screen Updates with Turbo Vision v3.1




  PROBLEM:
  --------

      Turbo Vision with the Borland C++ and Application Frameworks
  3.1 package seems very slow, much slower that the previous
  version, in fact.  What happened and how can I fix it?


  SOLUTION:
  ---------

      The problem is twofold:  One, snow checking was inadvertently
  turned on by default and two, the new operator that is in TV.LIB
  has debugging code compiled in with it.  Fortunately, the
  solution to these problems is very simple.  As a Borland C++ and
  Application Frameworks customer, you also have the source code to
  Turbo Vision.  You will need it to fix these problems, and here
  is how you do it.

      (1)  To fix the snow checking problem, go to the
  TVISION\SOURCE directory of the product and edit the file
  TSCREEN.CPP.  Change line 42 from

         Boolean near TScreen::checkSnow = True;

      to

         Boolean near TScreen::checkSnow = False;

      Recompile the module with the following command line.  You
  may need to make adjustments to the include directory path for
  the compiler to find <tv.h>.  (See the 3.1 User's Guide p. 172
  and p. 174-177 for details.)

         bcc -c -P -O1 -ml tscreen.cpp
         tlib /0 ..\lib\tv.lib -+tscreen.obj

      This will compile TSCREEN.CPP and add it to the Turbo Vision
  Library for later use.  If you only installed the Integrated
  Development environment on your system, you can rebuild this
  module by setting the following options and compiling
  TSCREEN.CPP.  Once the module has been compiled, execute the TLIB
  command shown above.













  PRODUCT  :  Borland C++                           NUMBER  :  1025
  VERSION  :  3.1
       OS  :  DOS
     DATE  :  October 23, 1992                         PAGE  :  2/2

    TITLE  :  Optimizing Screen Updates with Turbo Vision v3.1




       Options | Compiler | Optimizations:
                           Set to smallest code.

       Options | Compiler | Code Generation:
                           Set for large memory model.

       Options | Directories:
                           Set the correct include paths.


      (2)  To remove the debugging code from the new operator, you
  only need to recompile the source for that module.  Recompile
  NEW.CPP with the following command line.  As in (1), you may need
  to make adjustments to the include paths used by the compiler.

          bcc -c -P -O1 -ml -DNDEBUG new.cpp
          tlib /0 ..\lib\tv.lib -+new.obj

      The -DNDEBUG defines the NDEBUG symbol and will cause
  compilation of NEW.CPP without the extra debugging code.  If you
  only installed the IDE, set the options listed above, and also
  set the following.  Once the module has been compiled, execute
  the TLIB command shown above.

          Options | Compiler | Code Generation | Defines:
                      Add NDEBUG to this line.

  Upon performing these two steps, the Turbo Vision library should
  again be performing at the speed it had in previous versions.