Fix std::optional value() build error on older macOS SDK

No longer happens on the buildbot, but for users building with an older
Xcode, still need to avoid using value().

Differential Revision: https://developer.blender.org/D14883

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/io/usd/intern/usd_writer_volume.cc b/source/blender/io/usd/intern/usd_writer_volume.cc
index b83ded1e5d0..4126be6966a 100644
--- a/source/blender/io/usd/intern/usd_writer_volume.cc
+++ b/source/blender/io/usd/intern/usd_writer_volume.cc
@@ -53,7 +53,7 @@ void USDVolumeWriter::do_write(HierarchyContext &context)
   }
 
   if (usd_export_context_.export_params.relative_paths) {
-    if (auto relative_vdb_file_path = construct_vdb_relative_file_path(vdb_file_path.value())) {
+    if (auto relative_vdb_file_path = construct_vdb_relative_file_path(*vdb_file_path)) {
       vdb_file_path = relative_vdb_file_path;
     }
     else {
@@ -75,7 +75,7 @@ void USDVolumeWriter::do_write(HierarchyContext &context)
     const pxr::SdfPath grid_path = volume_path.AppendPath(pxr::SdfPath(grid_id));
     pxr::UsdVolOpenVDBAsset usd_grid = pxr::UsdVolOpenVDBAsset::Define(stage, grid_path);
     usd_grid.GetFieldNameAttr().Set(pxr::TfToken(grid_name), timecode);
-    usd_grid.GetFilePathAttr().Set(pxr::SdfAssetPath(vdb_file_path.value()), timecode);
+    usd_grid.GetFilePathAttr().Set(pxr::SdfAssetPath(*vdb_file_path), timecode);
     usd_volume.CreateFieldRelationship(pxr::TfToken(grid_id), grid_path);
   }
 
@@ -107,7 +107,7 @@ std::optional<std::string> USDVolumeWriter::resolve_vdb_file(const Volume *volum
 
   if (!vdb_file_path.has_value()) {
     vdb_file_path = BKE_volume_grids_frame_filepath(volume);
-    if (vdb_file_path.value().empty()) {
+    if (vdb_file_path->empty()) {
       return std::nullopt;
     }
   }