libpng

Build differently named 32 and 64 bit binaries for libpng that link to differently named zlib binaries

PREREQUISITES

1. libpng source code: tested with libpng 1.2.53
2. fnr: tested with fnr v1.8.1
3. msvc: tested with MSVS 2019 Community Edition
4. zlib binaries: tested with zlib 1.2.8
5. These libpng build scripts

STEPS

1. Copy fnr.exe to C:\local\libs\fnr\bin
2. Extract libpng source to C:\local\temp\libpng (so that source is in C:\local\temp\libpng\lpng12x)
3. Place zlib in C:\local\libs\zlib such that zlib64.lib and zlib32.lib are in C:\local\libs\zlib\lib
4. Extract the scripts in zlib_1.2.x_build_batch.7z to C:\local\temp\zlib
   1. Build by running Build.bat
   2. Files will be places in C:\local\libs\libpng