Persistence of Vision Raytracer
        What's New
-------------------------------
      Ver. 0.5 BETA
 
 - NEW Case sensitiviy options:     
   In dat files...
   > case_sensitive_yes -- All words checked for exact case. Keywords must be
                           in upper case. (*Old DKB Style*)
   > case_sensitive_no  -- Case is ignored for all words.
   > case_sensitive_opt -- DEFAULT - All words checked for exact case except
                           keywords. Keywords will be accepted in upper and/or
                           lower case. 
   -> command line -- /tY = yes, /tN = no, /tO = opt
 
 - cnvdat.c to convert old dat files included with pvsrc.
 
 - C++ style commenting (\\ & /* */) added by Drew Wells

 - # and ; are now ignored by the tokenizer/parser for those who would like
   to use them. #include is now ok.
 
 - Sample dat files converted to lower case keywords
 
 - New stats display outputs to stdout for better redirection.
 
 - New lighting routines by David Buck.
 
 - The declared colors Red, Green, and Blue in colors.dat are now CRed, CBlue,
   CGreen.
 
 - The declared quadric Sphere in shapes.dat is now QSphere.
 
 - Textures.dat has been cleaned up and commented.
 
 - Height fields added by Doug Muir

 - Bump Mapping added by Doug Muir and Drew Wells
 
 - Materials mapping added by Drew Wells.

 - Gouge mapping from old code by Drew Wells & Doug Muir added by Aaron Collins.

 - Time to trace display added to program stats by Bill Pulver.

 - ONION & LEOPARD textures added by Scott Taylor.

 - IBM-PC grayscale display option was thought of by both Scott Taylor and
   Grant Hess.  Actual implementation of it by Aaron Collins.

 
 - Interpolation options to smooth the image and bump maps from code by
   Girish T. Hagan added by Drew Wells

 - Verbose option now displays more information, including file   
   being traced, resolution, and current line number of how many total.
 
 - New screen credit style.

 - Option +vO added to allow old-style terse verbose (just line #'s).

 - Wood texture bug found by John Swenson fixed. Wood now uses true
   cylinders. This may affect some old pictures, but is more realistic.

 - Texture.doc describes the steps to add a new texture to the source.

 - Added Alexander Enzmann's latest modifications:

  A. Revised 4th order (Quartic) surfaces for better results.  When using the
     new Sturmian Sequences for QUARTICS, The digial acne is now all but
     vanquished!

  B. New code giving the ability to render 5th and 6th order surfaces.  These
     use the new Sturmian Sequences to solve the surface intersections.

  C. Bezier bicubic patch surfaces!  -  Smooth curved surfaces are implemented
     by breaking the curve into tiny subpatches when rendering.  Teapots,
     anyone?

  D. "CLIPPING" primitives added.  These work almost like "BOUNDING" shapes,
     but will cause surfaces protruding beyond the bound to be cut off.  The
     BOUNDED_BY primitive may cause this to happen but it is not guaranteed
     to, nor was it meant to be used that way.  Before the CLIPPED_BY was
     added you needed to CSG with a clear box or sphere shape to get this
     effect.  The new CLIPPED_BY tests are much, much faster than CSG tests.

  E. MacIntosh color display output routines are now included.

  F. A few of the larger static data items are now malloc'ed instead.

  G. Made more universal compiler-specific header strings for fopen() binary
     modes "rb", "wb", etc., and for credit printout and ending program
     actions.  All of them have default definitions in FRAME.H if left
     unspecified.  For porting to other machines or compilers, check FRAME.H
     first for the default definition, then add in the definition to the
     machine-specific header files if they need modification.

  H. IBM color palette changes allow use of 3-3-2 RGB display using 256 colors
     on (S)VGA display adapters.  This uses 3 bits for R, 3 for G and 2 for B.
     It is different than the HSV coloring system in that while the colors are
     less accurate, there are more shades of them.  Can be better for showing
     shadows and gradients, etc.

  I. Added the TRANSMIT keyword as a flag for whether or not the object will
     transmit light without refracting it.  Follow the keyword with either 0.0
     or 1.0 to turn off or on the TRANSMITtance of an object.  This is rather
     like the old ALPHA facility before it was interwoven into the REFRACTION
     algorithm.  The idea behind this is that you may want to specify a
     different level of TRANSMITtance vs. REFRACTION.

  J. Added new mapping options, sphere, cylinder, torus, etc.

 - Added changes made by Aaron A. Collins:

  A. Made exit codes consistent throughout.  The program now returns an exit
     code (ERRORLEVEL for you IBM-er's) of 1 if unsuccessful or 0 of all went
     well with the trace.

  B. Raised number of prioq' from 20 to 32.  This should cure some instances
     of crash during parsing that have been reported.

  C. Added display "greyscale" option to make all displayed hues of red,
     green and blue equal and of specially weighted value.  The weighting used
     is that for B/W television, which emulates the response of the human eye.
     The IBM specific code also includes a grey-scale optimized palette using
     64 levels of grey.  This will display nice smooth gradients and shadows,
     etc. and generally looks better than the color display routines now used.
     Please note that this option only affects the colors used for the
     onscreen display.  The output file will still be in full, true 24-bit
     living color!

     Note this will work on any machine's display adapter at any resolution.
     VGA palette code and the general idea of greyscaling the display output
     was courtesy of Grant Hess and Scott Taylor.

  D. The IBM version supports the Hercules Graphics Workstation card now, and
     should work on other TIGA-based 24-bit color cards as well.  The 16 and
     24-bit modes of the card are supported at 512x480 resolution.  The code
     for the HGWS/TIGA was provided courtesy of Jay S. Curtis.

  E. If no file was requested to be generated (-f), which is extremely rare,
     the program locked up and died.  This is now fixed.

  F. The Macintosh conversion of DKB 2.12 out there called MACPORT.CPT is now
     included with PV-Ray.  This includes a better GUI-oriented interface
     and (I believe) color display routines.  This port was done by Thomas
     Okken.  Among his fixes was a solution that I had heard of and had since
     forgotten about:  Two ANSI-C reserved words "entry" and "power" were used
     as formal function parameters.  These have been changed to something
     universally inoffensive.

  G. Someone (unfortunately there were no credits given to relate) had
     released the file XENIXPRT.DOC which was also incorporated into the
     new release.  This makes the program port to SCO Xenix's "C" compiler
     nicely (with work-arounds for their buggy "floor()" function).  This fix
     also uncomplicates some of the quartic math routines which some other
     not-quite-up-to-speed "C" compilers (which shall remain nameless) also
     tossed their cookies on.

  H. The fixed VESA routines and Sierra HiColor routines by Charles Marslett
     (CIS: 73317,3662) are now added to POV-Ray.  These changes now allow
     32,768 colors on VESA or Tseng Labs 4000 chip set SVGA cards equipped
     with Sierra HiColor palette DAC's.  These modifications also fixed the
     VESA SVGA adapter display routines (the original VESA routines were
     converted from IBM assembler, and didn't work, because I never had a
     VESA compatible SVGA card to try them on!)  Also included in Charles'
     fixes were support of 800x600x256 (Tseng 3000, 4000, and VESA) and
     1024x760x256 (Tseng 4000 and VESA) and 1280x1024x256 (sorry, VESA only)
     display modes.

  I. Added global display parameter "Palette option" that will use alternate
     palette color selection methods, if applicable.  For all machine-specific
     ports there is mode '0' or unspecified (default), which is the standard
     method used in previous versions, and 'G', for grey-scale display.  To
     use a palette option, simply add the mode letter (ex. 'g' or '0') after
     specifying the type of display (i.e. "+d3g" to use the greyscale option
     on video mode 3.)  If you use the display autodetection of PV-Ray by
     normally saying just "+d", use the option "+d0g" to add grey scaling but
     still use the same autodetected video mode.  Specifiying the default of
     just "+d" is now equivalent to saying "+d00".  The IBM-specific port also
     includes the palette option '3' for using a 3-3-2 palette instead of the
     usual HSV->RGB one (see #H in Alexander Enzmann's changes above).  The
     IBM port also uses a greyscale-optimized palette of 64 continuous shades
     of grey if the 'G' palette option is selected (see #C above).  The IBM
     port also now supports the Sierra HiColor palette DAC, by using palette
     option 'H' (see #H above).
