1Instructions for building libpng using Microsoft Visual Studio
2==============================================================
3
4Copyright (c) 2018 Cosmin Truta
5Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
6
7This code is released under the libpng license.
8For conditions of distribution and use, see the disclaimer and license
9in png.h
10
11This directory contains a solution for building libpng under Microsoft
12Visual Studio 2010.  It may also work under later versions of Visual
13Studio.  You should be familiar with Visual Studio before using this
14solution.
15
16Initial preparations
17--------------------
18You must enter some information in zlib.props before attempting to
19build with this 'solution'.  Please read and edit zlib.props first.
20You will probably not be familiar with the contents of zlib.props -
21do not worry, it is mostly harmless.
22
23This is all you need to do to build the 'release' and 'release library'
24configurations.
25
26Debugging
27---------
28The release configurations default to /Ox optimization.  Full debugging
29information is produced (in the .pdb), but if you encounter a problem
30the optimization may make it difficult to debug.  Simply rebuild with a
31lower optimization level (e.g. /Od.)
32
33Linking your application
34------------------------
35Normally you should link against the 'release' configuration.  This
36builds a DLL for libpng with the default runtime options used by Visual
37Studio.  In particular the runtime library is the "MultiThreaded DLL"
38version.  If you use Visual Studio defaults to build your application,
39you should have no problems.
40
41If you don't use the Visual Studio defaults your application must still
42be built with the default runtime option (/MD).  If, for some reason,
43it is not then your application will crash inside libpng16.dll as soon
44as libpng tries to read from a file handle you pass in.
45
46If you do not want to use the DLL, and prefer static linking instead,
47you may choose the 'release library' configuration.  This is built with
48a non-standard runtime library - the "MultiThreaded" version.  When you
49build your application, it must be compiled with this option (/MT),
50otherwise it will not build (if you are lucky) or it will crash (if you
51are not.) See the WARNING file that is distributed with this README.
52
53Stop reading here
54-----------------
55You have enough information to build a working application.
56
57Debug versions have limited support
58-----------------------------------
59This solution includes limited support for debug versions of libpng.
60You do not need these unless your own solution itself uses debug builds
61(it is far more effective to debug on the release builds, there is no
62point building a special debug build unless you have heap corruption
63problems that you can't track down.)
64
65The debug build of libpng is minimally supported.  Support for debug
66builds of zlib is also minimal.  Please keep this in mind, if you want
67to use it.
68
69WARNING
70-------
71Libpng 1.6.x does not use the default run-time library when building
72static library builds of libpng; instead of the shared DLL runtime, it
73uses a static runtime.  If you need to change this, make sure to change
74the setting on all the relevant projects:
75
76    libpng
77    zlib
78    all the test programs
79
80The runtime library settings for each build are as follows:
81
82               Release        Debug
83    DLL         /MD            /MDd
84    Library     /MT            /MTd
85
86Also, be sure to build libpng, zlib, and your project, all for the same
87platform (e.g., 32-bit or 64-bit).
88