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ktx/external/astc-encoder/Utils/Example/README.md

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+# Library usage example
+
+This is a minimal example of using the astcenc codec as a library in another
+project. This sample shows:
+
+  * How to include astcenc as an external project CMake dependency.
+  * How to use the API to compress and decompress an image.
+
+For sake of simplicity the example application uses fixed compression settings,
+reading an uncompressed LDR image, compressing using 6x6 blocks at medium
+quality, and then decompressing and writing the decompressed image back to disk
+as a PNG file.
+
+## Building
+
+:warning: For sake of simplicity the example CMake project uses the CMake
+`ExternalProject` mechanism to import the astcenc project from GitHub. This is
+trivial to integrate, but requires network access during the build to pull the
+astcenc project.
+
+Most users will want to store a copy of astcenc in a project sub-directory,
+e.g. by using git submodules, and then use `add_subdirectory()` to include the
+project in their build. This allows the user to directly use the astcenc core
+library as a link requirement via `target_link_libraries()`, without the
+additional plumbing that `ExternalProject` requires.
+
+### Linux and macOS
+
+From the `./Utils/Example` directory.
+
+```
+mkdir build
+cd build
+cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release ..
+make -j8
+```
+
+### Windows
+
+From the `./Utils/Example` directory, in a Visual Studio command prompt.
+
+```
+mkdir build
+cd build
+cmake -G "NMake Makefiles" -DCMAKE_BUILD_TYPE=Release ..
+nmake
+```
+
+## Running
+
+From the build directory above.
+
+```
+astcenc_example <input.png> <output.png>
+```