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README.md

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+# NorthstarStubs
+
+D3D11 and GFSDK stubs for the Northstar dedicated server.
+
+These stubs were originally developed for and are included in [pg9182's docker image](https://github.com/pg9182/northstar-dedicated) to eliminate the need for a real or emulated GPU and the resulting overhead (~1GB of RAM on Linux, multiple GB on Windows, on emulated GPUs). Northstar *unreleased* and later will include these stubs by default.
+
+## Development
+
+### Build
+
+To compile the stubs on Linux, install mingw-w64 (both GCC and Clang work fine) and meson, then run:
+
+```bash
+meson setup --cross-file misc/mingw-w64-cross.txt build
+meson compile -C build
+meson install -C build --destdir destdir
+```
+
+### Usage
+
+These stubs should be loaded in place of the original DLLs. On Windows, place in the `bin/x64_retail` directory, overwriting the existing DLLs. On Linux/Wine, put them in the same directory as the game executable, and set the Wine DLL overrides such that d3d11 is native and d3d9 is not present.
+
+The stubs can also be loaded via a launcher from an absolute path with LoadLibraryEx since relative imports will automatically refer to the first DLL loaded with the same name.
+
+If the stubs have loaded correctly, you should see a message in the console like `initializing d3d11 stub for northstar`.
+
+See [here](https://docs.microsoft.com/en-us/windows/win32/dlls/dynamic-link-library-search-order) for more information about the DLL search order on Windows.