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ktx/external/lodepng/README.md

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+LodePNG
+-------
+
+PNG encoder and decoder in C and C++, without dependencies
+
+Home page: http://lodev.org/lodepng/
+
+### Documentation
+
+Detailed documentation is included in a large comment in the second half of the
+header file `lodepng.h`.
+
+Source code examples using LodePNG can be found in the examples directory.
+
+An FAQ can be found on http://lodev.org/lodepng/
+
+### Building
+
+Only two files are needed to encode and decode PNGs:
+
+* `lodepng.cpp` (or renamed to `lodepng.c`)
+* `lodepng.h`
+
+All other files are just source code examples, tests, misc utilities, etc...,
+which are normally not needed in projects using this.
+
+You can include the files directly in your project's source tree and its
+makefile, IDE project file, or other build system. No library is necessary.
+
+In addition to C++, LodePNG also supports ANSI C (C89), with all the same
+functionality: C++ only adds extra convenience API.
+
+For C, rename `lodepng.cpp` to `lodepng.c`.
+
+Consider using git submodules to include LodePNG in your project.
+
+### Compiling in C++
+
+If you have a hypothetical `your_program.cpp` that #includes and uses `lodepng.h`,
+you can build as follows:
+
+`g++ your_program.cpp lodepng.cpp -Wall -Wextra -pedantic -ansi -O3`
+
+or:
+
+`clang++ your_program.cpp lodepng.cpp -Wall -Wextra -pedantic -ansi -O3`
+
+This shows compiler flags it was designed for, but normally one would use the
+compiler or build system of their project instead of those commands, and other
+C++ compilers are supported.
+
+### Compiling in C
+
+Rename `lodepng.cpp` to `lodepng.c` for this.
+
+If you have a hypothetical your_program.c that #includes and uses lodepng.h,
+you can build as follows:
+
+`gcc your_program.c lodepng.c -ansi -pedantic -Wall -Wextra -O3`
+
+or
+
+`clang your_program.c lodepng.c -ansi -pedantic -Wall -Wextra -O3`
+
+This shows compiler flags it was designed for, but normally one would use the
+compiler or build system of their project instead of those commands, and other
+C compilers are supported.
+
+### Makefile
+
+There is a Makefile, but this is not intended for using LodePNG itself since the
+way to use that one is to include its source files in your program. The Makefile
+only builds development and testing utilities. It can be used as follows:
+
+`make -j`