cesium/Documentation/Contributors/DracoModuleManagement

Updating the Draco JavaScript Decoder Module

We use a custom build of the Draco decoder JavaScript module to allow for IE11 compatibility.

1. Download and install a make tool.

   • Preferably, use Linux or the Linux Subsystem for Windows 10 and make to build.
   • Optionally, MSYS2. Follow installation instructions and add the path to MSYS2's usr/bin to your PATH. For example, if the path is C:\msys64\usr\bin, run PATH=%PATH%;C:\msys64\usr\bin.

2. Download (or checkout the tag of) an official Draco release.

3. Download and install Emscripten

4. In a seperate directory, follow the CMake JavaScript Encoder/Decoder Instructions. When running cmake, specify "Unix Makefiles" as the target, and including the flag -DIE_COMPATIBLE=true, ie.

   cmake ..\path\to\draco -G "Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE="absolute\path\emscripten\cmake\Modules\Platforms\Emscripten.cmake" -DIE_COMPATIBLE=true
   

5. In that directory, build with make -j.

6. Copy the output draco_decoder.js file to the Source\ThirdParty\Workers directory.