projects/vstudio/readme.txt - third_party/libpng - Git at Google


 VisualStudio instructions

 libpng version 1.5.0beta19 - April 20, 2010

 Copyright (c) 1998-2010 Glenn Randers-Pehrson

 This code is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
 and license in png.h

 This diretory  contains support for building libpng under MicroSoft
 VisualStudio 2010.  It may also work under later versions of VisualStudio.
 You should be familiar with VisualStudio before using this directory.

 Initial preparations
 ====================
 You should install the 'official' build of zlib on your system - follow the
 instructions provided on http://www.zlib.net.  When a new release is being
 made of zlib the instructions disappear for a while until the new official
 build is available.  You will have to wait.

 You must enter some information in zlib.props before attempting to build
 with this 'solution'.  Please read and edit zlib.props first.  You will
 probably not be familiar with the contents of zlib.props - do not worry,
 it is mostly harmless.

 Make sure that your official build layout matches the requirements listed
 in zlib.props.  Prior to zlib-1.2.4 the official build (1.2.3) placed
 include and library files in different directories - if you find this
 has happened just put them all in the same directory.

 This is all you need to do to build the 'release' and 'release library'
 configurations.

 Debugging
 =========
 The release configurations default to /Ox optimization.  Full debugging
 information is produced (in the .pdb), but if you encounter a problem the
 optimization may make it difficult to debug.  Simply rebuild with a lower
 optimization level (e.g. /Od.)

 Stop reading here
 =================
 You have enough information to build a working application.

 Debug versions have limited support
 ===================================
 This solution includes limited support for debug versions of libpng.  You
 do not need these unless your own solution itself uses debug builds (it is
 far more effective to debug on the release builds, there is no point building
 a special debug build.)

 If, despite the previous paragraph, you still feel you need a debug build you
 will have to download the zlib source as well (http://www.zlib.net) and include
 the directory where you unpack it in zlib.props.  This solution will then be
 able to build a minimal zlib sufficient for libpng.  This build is only
 suitable for making a debug libpng.

 The debug build of libpng is minimally supported.  Support for debug builds of
 zlib is also minimal.  You really don't want to do this.

 This solution only supports the Multi-Threaded DLL C Runtime
 ============================================================
 If you examine the solution you will find that it very deliberately lists
 exactly which MicroSoft DLLs it is linking against.  It explicitly links
 against msvcrt.lib.  The debug version links against msvcrtd.lib (this is
 why it is a debug version - it's nothing to do with having any special
 debug support, it doesn't).

 These versions of the MicroSoft C runtime correspond to the compiler flags
 /MD (release) and /MDd (debug) - the "Multi-Threaded DLL" implementation of the
 C runtime library.

 If you need to change this then you will have to make sure that both the
 compiler flags and the ".lib" in the linker dependences match up.  Fortunately
 neither zlib nor libpng require libraries other than a C runtime and
 kernel32.

 You cannot pass (FILE*) objects from a different runtime (including msvcrtd
 to msvcrt) to libpng.  If you do then your program will crash within libpng
 when it first makes a file read or write call.

 It is likely if you have read this far that you have found you can't avoid
 having multiple C runtimes in your program.  This is OK, it does work, but
 you will have to implement the libpng file read/write callbacks rather than
 using the internal libpng default.  This is easy.

	VisualStudio instructions

	libpng version 1.5.0beta19 - April 20, 2010

	Copyright (c) 1998-2010 Glenn Randers-Pehrson

	This code is released under the libpng license.
	For conditions of distribution and use, see the disclaimer
	and license in png.h

	This diretory contains support for building libpng under MicroSoft
	VisualStudio 2010. It may also work under later versions of VisualStudio.
	You should be familiar with VisualStudio before using this directory.

	Initial preparations
	====================
	You should install the 'official' build of zlib on your system - follow the
	instructions provided on http://www.zlib.net. When a new release is being
	made of zlib the instructions disappear for a while until the new official
	build is available. You will have to wait.

	You must enter some information in zlib.props before attempting to build
	with this 'solution'. Please read and edit zlib.props first. You will
	probably not be familiar with the contents of zlib.props - do not worry,
	it is mostly harmless.

	Make sure that your official build layout matches the requirements listed
	in zlib.props. Prior to zlib-1.2.4 the official build (1.2.3) placed
	include and library files in different directories - if you find this
	has happened just put them all in the same directory.

	This is all you need to do to build the 'release' and 'release library'
	configurations.

	Debugging
	=========
	The release configurations default to /Ox optimization. Full debugging
	information is produced (in the .pdb), but if you encounter a problem the
	optimization may make it difficult to debug. Simply rebuild with a lower
	optimization level (e.g. /Od.)

	Stop reading here
	=================
	You have enough information to build a working application.

	Debug versions have limited support
	===================================
	This solution includes limited support for debug versions of libpng. You
	do not need these unless your own solution itself uses debug builds (it is
	far more effective to debug on the release builds, there is no point building
	a special debug build.)

	If, despite the previous paragraph, you still feel you need a debug build you
	will have to download the zlib source as well (http://www.zlib.net) and include
	the directory where you unpack it in zlib.props. This solution will then be
	able to build a minimal zlib sufficient for libpng. This build is only
	suitable for making a debug libpng.

	The debug build of libpng is minimally supported. Support for debug builds of
	zlib is also minimal. You really don't want to do this.

	This solution only supports the Multi-Threaded DLL C Runtime
	============================================================
	If you examine the solution you will find that it very deliberately lists
	exactly which MicroSoft DLLs it is linking against. It explicitly links
	against msvcrt.lib. The debug version links against msvcrtd.lib (this is
	why it is a debug version - it's nothing to do with having any special
	debug support, it doesn't).

	These versions of the MicroSoft C runtime correspond to the compiler flags
	/MD (release) and /MDd (debug) - the "Multi-Threaded DLL" implementation of the
	C runtime library.

	If you need to change this then you will have to make sure that both the
	compiler flags and the ".lib" in the linker dependences match up. Fortunately
	neither zlib nor libpng require libraries other than a C runtime and
	kernel32.

	You cannot pass (FILE*) objects from a different runtime (including msvcrtd
	to msvcrt) to libpng. If you do then your program will crash within libpng
	when it first makes a file read or write call.

	It is likely if you have read this far that you have found you can't avoid
	having multiple C runtimes in your program. This is OK, it does work, but
	you will have to implement the libpng file read/write callbacks rather than
	using the internal libpng default. This is easy.