Support MacOS build on Appveyor

appveyor.yml

@@ -1,9 +1,17 @@
 # version format
 version: 1.0.{build}
 
-environment:
+image:
+  - Visual Studio 2017
+  - MacOS
+
+for:
+-
   matrix:
-    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+    only:
+      - image: Visual Studio 2017
+  
+  environment:
     PYTHON: "C:\\Python36-x64"
     FBXSDK_SDKS: sdk
 
@@ -56,3 +64,47 @@ deploy:
     on:
       branch: master
       APPVEYOR_REPO_TAG: true
+
+-
+  matrix:
+    only:
+      - image: macOS
+  
+  install:
+  - export HOMEBREW_NO_AUTO_UPDATE=true # Disable homebrew auto-update
+  # -------------------------------------------------------------------
+  # We can directly install conan from brew instead of pip
+  # - export PATH="/usr/local/opt/python/libexec/bin:$PATH"
+  # - brew install python # Note: python has been installed in appveyor
+  # - pip --version
+  # - pip install conan
+  # -------------------------------------------------------------------
+  - brew install zstd conan
+  - conan --version
+  - curl -sL "https://github.com/zellski/FBXSDK-Darwin/archive/2019.2.tar.gz" | tar xz --strip-components=1 */sdk
+  - zstd -d -r --rm sdk
+  - conan user
+  - conan remote add --force bincrafters https://api.bintray.com/conan/bincrafters/public-conan
+
+  build_script:
+  - conan install . -i build -s build_type=Release -s compiler=apple-clang -s compiler.version=10.0 -s compiler.libcxx=libc++
+  - conan build . -bf build
+  - mv build/FBX2glTF build/FBX2glTF-darwin-x64
+
+  test: off
+
+  artifacts:
+    - path: build/FBX2glTF-darwin-x64
+
+  deploy:
+    tag: $(APPVEYOR_REPO_TAG_NAME)
+    description: ''
+    provider: GitHub
+    auth_token:
+      secure: OSvhQP0O9uaH+OFOJpbGiiBMRTOJ+H/VJHqVBhq39RNDnOfUEr/yjJNKh3JSdNqj
+    artifact: build/FBX2glTF-darwin-x64
+    draft: true
+    prerelease: true
+    on:
+      branch: master
+      APPVEYOR_REPO_TAG: true