Add csg boolean operators using elalish/manifold.

Co-Authored-By: 31 <31eee384@gmail.com>

modules/csg/SCsub

@@ -5,7 +5,53 @@ Import("env_modules")
 
 env_csg = env_modules.Clone()
 
-# Godot source files
+# Thirdparty source files
+
+thirdparty_obj = []
+
+thirdparty_dir = "#thirdparty/manifold/"
+thirdparty_sources = [
+    "src/polygon/src/polygon.cpp",
+    "src/manifold/src/constructors.cpp",
+    "src/manifold/src/edge_op.cpp",
+    "src/manifold/src/face_op.cpp",
+    "src/manifold/src/impl.cpp",
+    "src/manifold/src/boolean_result.cpp",
+    "src/manifold/src/boolean3.cpp",
+    "src/manifold/src/manifold.cpp",
+    "src/manifold/src/properties.cpp",
+    "src/manifold/src/smoothing.cpp",
+    "src/manifold/src/sort.cpp",
+    "src/manifold/src/csg_tree.cpp",
+    "src/manifold/src/subdivision.cpp",
+    "src/collider/src/collider.cpp",
+]
+
+env_csg.Append(CPPDEFINES=["THRUST_DEVICE_SYSTEM=THRUST_DEVICE_SYSTEM_CPP"])
+env_csg.Append(LINKFLAGS=["-fno-exceptions"])
+env_csg.Append(LINKFLAGS=["-fno-duplicated-branches"])
+
+thirdparty_sources = [thirdparty_dir + file for file in thirdparty_sources]
+env_csg.Prepend(
+    CPPPATH=[
+        "#thirdparty/thrust",
+        "#thirdparty/glm",
+        "#thirdparty/quickhull",
+        thirdparty_dir + "src/polygon/include",
+        thirdparty_dir + "src/manifold/include",
+        thirdparty_dir + "src/utilities/include",
+        thirdparty_dir + "src/collider/include",
+        thirdparty_dir + "src/third_party",
+        thirdparty_dir + "src/third_party/quickhull",
+    ]
+)
+env_thirdparty = env_csg.Clone()
+env_thirdparty.disable_warnings()
+env_thirdparty.add_source_files(thirdparty_obj, thirdparty_sources)
+env_thirdparty.add_source_files(thirdparty_obj, "#thirdparty/quickhull/QuickHull.cpp")
+env.modules_sources += thirdparty_obj
+
+# Godot's own source files
 env_csg.add_source_files(env.modules_sources, "*.cpp")
 if env.editor_build:
     env_csg.add_source_files(env.modules_sources, "editor/*.cpp")