Describe clang-cl + MSVC SDK cross compile procedure.

README.md

@@ -115,7 +115,8 @@ If you need commercial support, eco-system development(e.g. plug-ins, DCC tools
 * [x] iOS
 * [x] macOS(Arm, x86-64)
 * [x] Windows 10 64bit or later
-  * [ ] Windows ARM(should work)
+  * [x] Windows ARM
+  * [x] clang-cl + MSVC SDK cross compile
 * [x] WebAssembly
   * Emscripten
     * See [examples/sdlviewer/](examples/sdlviewer) example.
@@ -365,6 +366,14 @@ then build TinyUSDZ by linking with this local Python build.
 > ci-build-vs2022.bat
 ```
 
+#### Cross compile with clang-cl + MSVC SDK on linux and run it on WINE(No Windows required at all solution!)
+
+clang-cl(MSVC cl.exe) + MSVC SDK cross compile is also supported.
+
+Please take a look at [doc/wine_cl.md](doc/wine_cl.md)
+
+You can build pure Windows build of TinyUSDZ on Linux CI machine.
+
 ## License
 
 TinyUSDZ is licensed under MIT license and Apache 2.0 license.

doc/wine_cl.md

@@ -0,0 +1,67 @@
+# WINE + clang-cl build of pure Win32/Win64 TinyUSDZ library
+
+TinyUSDZ can be compiled with clang-cl + MSVC SDK.
+And can run it on top of WINE. Pure Windows C/C++ app/library build on Linux!
+
+## MSVC SDK license
+
+https://devblogs.microsoft.com/cppblog/updates-to-visual-studio-build-tools-license-for-c-and-cpp-open-source-projects/
+
+MSVC SDK(Visual Studio Build Tools, Microsoft C++ Build Tools) EULA has been relaxed to use it(grab a copy) for OSS build without Visual Studio license.
+
+Note that Windows SDK does not require VS license.
+
+## Setup
+
+Download llvm prebuilt for your HOST architecure(e.g. Ubuntu x86_64 if you are using x64 Linux()
+Note that ubuntu prebuit is provided up to 14.0.0
+
+https://github.com/llvm/llvm-project/releases/tag/llvmorg-14.0.0
+
+Install Ninja build tool.
+
+### WSL
+
+On WSL, easy way is instll VSBT in Windows side.
+
+https://visualstudio.microsoft.com/visual-cpp-build-tools/
+
+You can also use `msvc-wine` in the following.
+
+### Linux(Ubuntu)
+
+https://github.com/mstorsjo/msvc-wine
+
+We recommend to use msvc-wine effort. It automates downloading MSVC SDK and Windows SDK and unpacking it.
+
+Note that recent msvc-wine makes foldername/filename lowercase.
+
+## Cross compile TinyUSDZ with clang-cl 
+
+Plase see `scripts/bootstrap-clang-cl-wsl.sh`
+
+```
+  cd build-clang-cl-wsl
+  cmake -G Ninja -DCMAKE_TOOLCHAIN_FILE="cmake/clang-cl-msvc-wsl.cmake" \
+    -DHOST_ARCH=x64 \
+    -DLLVM_NATIVE_TOOLCHAIN="/mnt/d/local/clang+llvm-14.0.0-x86_64-linux-gnu-ubuntu-18.04/" \
+    -DMSVC_BASE:FILEPATH="/mnt/d/VC/Tools/MSVC/14.26.28801/" \
+    -DWINSDK_BASE="/mnt/d/winsdk/10/" \
+    -DWINSDK_VER="10.0.18362.0" \
+    ..
+```
+
+Edit `MSVC_BASE` and `WINSDK_BASE`(You can use Windows path if you are cross-compiling on WSL), and `WINSDK_VER` to fit your MSVC SDK, Windows SDK.
+
+Note that recent msvc-wine makes foldername/filename lowercase. You may need to edit some foldername/filename(e.g. `Windows.h -> windows.h` in `cmake/clang-cl-msvc-wsl.cmake`
+
+## Run on Wine.
+
+`vcruntime**.dll` and some MSVC/ucrt dlls are required in the PATH.
+You can set it through `WINEPATH`
+
+```
+$ WINEPATH="%PATH%;C:\path\to\dlls" wine64 ./usda_parser.exe
+```
+
+EoL.