From 5858ff8e2c22beeadfc212682b3264dda4b4e159 Mon Sep 17 00:00:00 2001
From: pca006132 <john.lck40@gmail.com>
Date: Sat, 5 Aug 2023 16:45:28 +0800
Subject: [PATCH] try enable tbb for windows

---
 .github/workflows/manifold.yml |  2 +-
 src/utilities/CMakeLists.txt   | 31 ++++++++++++++++++++++++++-----
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/manifold.yml b/.github/workflows/manifold.yml
index bbc606292..a4d082bb5 100644
--- a/.github/workflows/manifold.yml
+++ b/.github/workflows/manifold.yml
@@ -144,7 +144,7 @@ jobs:
     timeout-minutes: 30
     strategy:
       matrix:
-        parallel_backend: [NONE]
+        parallel_backend: [NONE, TBB]
         cuda_support: [OFF]
       max-parallel: 1
     runs-on: windows-2019
diff --git a/src/utilities/CMakeLists.txt b/src/utilities/CMakeLists.txt
index 1e7d45db9..b0f96d0c7 100644
--- a/src/utilities/CMakeLists.txt
+++ b/src/utilities/CMakeLists.txt
@@ -29,11 +29,32 @@ if(MANIFOLD_PAR STREQUAL "OMP")
     target_compile_options(${PROJECT_NAME} PUBLIC -DMANIFOLD_PAR='O' -fopenmp)
     target_link_options(${PROJECT_NAME} PUBLIC -fopenmp)
 elseif(MANIFOLD_PAR STREQUAL "TBB")
-    find_package(PkgConfig REQUIRED)
-    pkg_check_modules(TBB REQUIRED tbb)
-    target_include_directories(${PROJECT_NAME} PUBLIC ${TBB_INCLUDE_DIRS})
+    find_package(TBB QUIET)
+    if(NOT TBB_FOUND)
+        find_package(PkgConfig)
+        if (PKG_CONFIG_FOUND)
+            pkg_check_modules(TBB tbb)
+        endif()
+    endif()
+    if(NOT TBB_FOUND)
+        message(STATUS "tbb not found, downloading from source")
+        set(TBB_TEST off)
+        set(TBB_STRICT off)
+        include(FetchContent)
+        FetchContent_Declare(TBB
+          GIT_REPOSITORY https://github.com/oneapi-src/oneTBB.git
+          GIT_TAG        v2021.10.0
+          GIT_SHALLOW    TRUE
+          GIT_PROGRESS   TRUE
+        )
+        FetchContent_MakeAvailable(TBB)
+    endif()
     target_compile_options(${PROJECT_NAME} PUBLIC -DMANIFOLD_PAR='T')
-    target_link_libraries(${PROJECT_NAME} PUBLIC ${TBB_LINK_LIBRARIES})
+    if(DEFINED TBB::tbb)
+      target_link_libraries(${PROJECT_NAME} PUBLIC TBB::tbb)
+    else()
+      target_link_libraries(${PROJECT_NAME} PUBLIC ${TBB_LINK_LIBRARIES})
+    endif()
 elseif(MANIFOLD_PAR STREQUAL "NONE")
     set(MANIFOLD_PAR "CPP")
 else()
@@ -63,4 +84,4 @@ if(MANIFOLD_DEBUG)
         PUBLIC -DMANIFOLD_DEBUG)
 endif()
 
-target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_17)
\ No newline at end of file
+target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_17)