[libpng16] Began a manual section about libpng15 to libpng16 differences.

1 files changed, 36 insertions, 11 deletions

diff --git a/libpng.3 b/libpng.3
index 7e1af1526..178796f7e 100644
--- a/libpng.3
+++ b/libpng.3
@@ -5153,19 +5153,20 @@ function) incorrectly returned a value of type png_uint_32.
 A. Changes that affect users of libpng
 
 There are no substantial API changes between the non-deprecated parts of
-the 1.4.5 API and the 1.5.0 API, however the ability to directly access
-the main libpng control structures, png_struct and png_info, deprecated
-in earlier versions of libpng, has been completely removed from
+the 1.4.5 API and the 1.5.0 API; however the ability to directly access
+members of the main libpng control structures, png_struct and png_info,
+deprecated in earlier versions of libpng, has been completely removed from
 libpng 1.5.
 
-We no longer include zlib.h in png.h.  Applications that need access
-to information in zlib.h will need to add the '#include "zlib.h"'
-directive.  It does not matter whether it is placed prior to or after
+We no longer include zlib.h in png.h.  The include statement has been moved
+to pngstruct.h, where it is not accessible by applications. Applications that
+need access to information in zlib.h will need to add the '#include "zlib.h"'
+directive.  It does not matter whether this is placed prior to or after
 the '"#include png.h"' directive.
 
 We moved the png_strcpy(), png_strncpy(), png_strlen(), png_memcpy(),
 png_memcmp(), png_sprintf, and png_memcpy() macros into a private
-header file (pngpriv.h) that is not accessible to applications.
+header file (pngpriv.h) that is not accessible by applications.
 
 In png_get_iCCP, the type of "profile" was changed from png_charpp
 to png_bytepp, and in png_set_iCCP, from png_charp to png_const_bytep.
@@ -5434,7 +5435,31 @@ pngusr.h a system builder may also define equivalent options in pngusr.dfa
 DFA_XTRA to the file name.  The makefiles in contrib/pngminim illustrate
 how to do this, and a case where pngusr.h is still required.
 
-.SH XI. Detecting libpng
+.SH XI.  Changes to Libpng from version 1.5.x to 1.6.x
+
+We no longer include string.h in png.h.  The include statement has been moved
+to pngpriv.h, where it is not accessible by applications.  Applications that
+need access to information in string.h must add an '#include "string.h"'
+directive.  It does not matter whether this is placed prior to or after
+the '"#include png.h"' directive.
+
+The following API are now DEPRECATED:
+   png_info_init_3()
+   png_convert_to_rfc1123() which has been replaced
+     with png_convert_to_rfc1123_buffer()
+   png_malloc_default()
+   png_free_default()
+
+The following has been removed:
+   png_get_io_chunk_name(), which has been replaced
+     with png_get_io_chunk_type().  The new
+     function returns a 32-bit integer instead of
+     a string.
+
+A "simplified API" has been added (see documentation in png.h and a simple
+example in contrib/examples/pngtopng.c)
+
+.SH XII.  Detecting libpng
 
 The png_get_io_ptr() function has been present since libpng-0.88, has never
 changed, and is unaffected by conditional compilation macros.  It is the
@@ -5443,7 +5468,7 @@ libpng version since 0.88.  In an autoconf "configure.in" you could use
 
     AC_CHECK_LIB(png, png_get_io_ptr, ...
 
-.SH XII. Source code repository
+.SH XIII. Source code repository
 
 Since about February 2009, version 1.2.34, libpng has been under "git" source
 control.  The git repository was built from old libpng-x.y.z.tar.gz files
@@ -5467,7 +5492,7 @@ simple verbal discriptions of bug fixes, reported either to the
 SourceForge bug tracker, to the png-mng-implement at lists.sf.net
 mailing list, or directly to glennrp.
 
-.SH XIII. Coding style
+.SH XV. Coding style
 
 Our coding style is similar to the "Allman" style, with curly
 braces on separate lines:
@@ -5579,7 +5604,7 @@ Lines do not exceed 80 characters.
 
 Other rules can be inferred by inspecting the libpng source.
 
-.SH XIV. Y2K Compliance in libpng
+.SH XV. Y2K Compliance in libpng
 
 December 22, 2011