initial commit

Signed-off-by: Peter Siegmund <mars3142@noreply.mars3142.dev>

libs/wxWidgets-3.3.1/3rdparty/libwebp/webp_js/README.md

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+# WebP JavaScript decoder
+
+```
+ __   __ ____ ____ ____     __  ____
+/  \\/  \  _ \  _ \  _ \   (__)/  __\
+\       /  __/ _  \  __/   _)  \_   \
+ \__\__/_____/____/_/     /____/____/
+```
+
+This file describes the compilation of libwebp into a JavaScript decoder using
+Emscripten and CMake.
+
+-   install the Emscripten SDK following the procedure described at:
+    https://emscripten.org/docs/getting_started/downloads.html#installation-instructions-using-the-emsdk-recommended
+    After installation, you should have some global variable positioned to the
+    location of the SDK. In particular, $EMSDK should point to the top-level
+    directory containing Emscripten tools.
+
+-   configure the project 'WEBP_JS' with CMake using:
+
+    ```shell
+    cd webp_js && \
+    emcmake cmake -DWEBP_BUILD_WEBP_JS=ON ../
+    ```
+
+-   compile webp.js using 'emmake make'.
+
+-   that's it! Upon completion, you should have the 'webp.js', 'webp.js.mem',
+    'webp_wasm.js' and 'webp_wasm.wasm' files generated.
+
+The callable JavaScript function is WebPToSDL(), which decodes a raw WebP
+bitstream into a canvas. See webp_js/index.html for a simple usage sample (see
+below for instructions).
+
+## Demo HTML page
+
+The HTML page webp_js/index.html requires the built files 'webp.js' and
+'webp.js.mem' to be copied to webp_js/. An HTTP server to serve the WebP image
+example is also needed. With Python, just run:
+
+```shell
+cd webp_js && python3 -m http.server 8080
+```
+
+and then navigate to http://localhost:8080 in your favorite browser.
+
+## Web-Assembly (WASM) version:
+
+CMakeLists.txt is configured to build the WASM version when using the option
+WEBP_BUILD_WEBP_JS=ON. The compilation step will assemble the files
+'webp_wasm.js' and 'webp_wasm.wasm' that you then need to copy to the webp_js/
+directory.
+
+See webp_js/index_wasm.html for a simple demo page using the WASM version of the
+library.
+
+## Caveats
+
+-   First decoding using the library is usually slower, due to just-in-time
+    compilation.