Links CUDA libraries when CUDA is enabled

This commit ensures that the example project links against the CUDA
runtime libraries when Open3D has been compiled with CUDA support.
It checks for the BUILD_CUDA_MODULE definition in the
INTERFACE_COMPILE_DEFINITIONS of the Open3D target and, if present,
links against the necessary CUDA libraries.

Author: eclipse0922

examples/cmake/open3d-cmake-find-package/CMakeLists.txt

@@ -16,9 +16,21 @@ endif()
 # Find installed Open3D, which exports Open3D::Open3D
 find_package(Open3D REQUIRED)
 
+# Check if Open3D was built with CUDA support and link CUDA if needed
+get_target_property(OPEN3D_COMPILE_DEFS Open3D::Open3D INTERFACE_COMPILE_DEFINITIONS)
+if(OPEN3D_COMPILE_DEFS AND "BUILD_CUDA_MODULE" IN_LIST OPEN3D_COMPILE_DEFS)
+    find_package(CUDAToolkit REQUIRED)
+    set(CUDA_LIBS CUDA::cudart)
+    if(WIN32)
+        list(APPEND CUDA_LIBS CUDA::cuda_driver)
+    endif()
+else()
+    set(CUDA_LIBS)
+endif()
+
 add_executable(Draw)
 target_sources(Draw PRIVATE Draw.cpp)
-target_link_libraries(Draw PRIVATE Open3D::Open3D)
+target_link_libraries(Draw PRIVATE Open3D::Open3D ${CUDA_LIBS})
 
 # On Windows if BUILD_SHARED_LIBS is enabled, copy .dll files to the executable directory
 if(WIN32)