3 files changed, 42 insertions, 17 deletions

diff --git a/intern/openvdb/intern/openvdb_dense_convert.cc b/intern/openvdb/intern/openvdb_dense_convert.cc
index ef52408bd93..10d5fb6402a 100644
--- a/intern/openvdb/intern/openvdb_dense_convert.cc
+++ b/intern/openvdb/intern/openvdb_dense_convert.cc
@@ -165,4 +165,19 @@ void OpenVDB_import_grid_vector(
 	}
 }
 
+openvdb::Name do_name_versionning(const openvdb::Name &name)
+{
+	openvdb::Name temp_name = name;
+
+	if (temp_name.find("_low", temp_name.size() - 4, 4) == temp_name.size() - 4) {
+		return temp_name.replace(temp_name.size() - 4, 4, " low");
+	}
+
+	if (temp_name.find("_old", temp_name.size() - 4, 4) == temp_name.size() - 4) {
+		return temp_name.replace(temp_name.size() - 4, 4, " old");
+	}
+
+	return temp_name;
+}
+
 }  /* namespace internal */
diff --git a/intern/openvdb/intern/openvdb_dense_convert.h b/intern/openvdb/intern/openvdb_dense_convert.h
index 284fd1ceeae..7882cafa06e 100644
--- a/intern/openvdb/intern/openvdb_dense_convert.h
+++ b/intern/openvdb/intern/openvdb_dense_convert.h
@@ -40,6 +40,10 @@
 
 namespace internal {
 
+/* Verify that the name does not correspond to the old format, in which case we
+ * need to replace the '_low' ending with ' low'. See T53802. */
+openvdb::Name do_name_versionning(const openvdb::Name &name);
+
 openvdb::Mat4R convertMatrix(const float mat[4][4]);
 
 template <typename GridType, typename T>
@@ -87,13 +91,19 @@ void OpenVDB_import_grid(
 {
 	using namespace openvdb;
 
-	if (!reader->hasGrid(name)) {
-		std::fprintf(stderr, "OpenVDB grid %s not found in file!\n", name.c_str());
-		memset(*data, 0, sizeof(T) * res[0] * res[1] * res[2]);
-		return;
+	openvdb::Name temp_name = name;
+
+	if (!reader->hasGrid(temp_name)) {
+		temp_name = do_name_versionning(temp_name);
+
+		if (!reader->hasGrid(temp_name)) {
+			std::fprintf(stderr, "OpenVDB grid %s not found in file!\n", temp_name.c_str());
+			memset(*data, 0, sizeof(T) * res[0] * res[1] * res[2]);
+			return;
+		}
 	}
 
-	typename GridType::Ptr grid = gridPtrCast<GridType>(reader->getGrid(name));
+	typename GridType::Ptr grid = gridPtrCast<GridType>(reader->getGrid(temp_name));
 	typename GridType::ConstAccessor acc = grid->getConstAccessor();
 
 	math::Coord xyz;
diff --git a/source/blender/blenkernel/intern/pointcache.c b/source/blender/blenkernel/intern/pointcache.c
index dc1c0da4401..a84dc056015 100644
--- a/source/blender/blenkernel/intern/pointcache.c
+++ b/source/blender/blenkernel/intern/pointcache.c
@@ -999,7 +999,7 @@ static int ptcache_smoke_openvdb_write(struct OpenVDBWriter *writer, void *smoke
 		OpenVDBWriter_add_meta_fl(writer, "blender/smoke/dx", dx);
 		OpenVDBWriter_add_meta_fl(writer, "blender/smoke/dt", dt);
 
-		const char *name = (!sds->wt) ? "density" : "density low";
+		const char *name = (!sds->wt) ? "density" : "density_low";
 		density_grid = OpenVDB_export_grid_fl(writer, name, dens, sds->res, sds->fluidmat, NULL);
 		clip_grid = sds->wt ? clip_grid : density_grid;
 
@@ -1007,20 +1007,20 @@ static int ptcache_smoke_openvdb_write(struct OpenVDBWriter *writer, void *smoke
 
 		if (fluid_fields & SM_ACTIVE_HEAT) {
 			OpenVDB_export_grid_fl(writer, "heat", heat, sds->res, sds->fluidmat, clip_grid);
-			OpenVDB_export_grid_fl(writer, "heat old", heatold, sds->res, sds->fluidmat, clip_grid);
+			OpenVDB_export_grid_fl(writer, "heat_old", heatold, sds->res, sds->fluidmat, clip_grid);
 		}
 
 		if (fluid_fields & SM_ACTIVE_FIRE) {
-			name = (!sds->wt) ? "flame" : "flame low";
+			name = (!sds->wt) ? "flame" : "flame_low";
 			OpenVDB_export_grid_fl(writer, name, flame, sds->res, sds->fluidmat, density_grid);
-			name = (!sds->wt) ? "fuel" : "fuel low";
+			name = (!sds->wt) ? "fuel" : "fuel_low";
 			OpenVDB_export_grid_fl(writer, name, fuel, sds->res, sds->fluidmat, density_grid);
-			name = (!sds->wt) ? "react" : "react low";
+			name = (!sds->wt) ? "react" : "react_low";
 			OpenVDB_export_grid_fl(writer, name, react, sds->res, sds->fluidmat, density_grid);
 		}
 
 		if (fluid_fields & SM_ACTIVE_COLORS) {
-			name = (!sds->wt) ? "color" : "color low";
+			name = (!sds->wt) ? "color" : "color_low";
 			OpenVDB_export_grid_vec(writer, name, r, g, b, sds->res, sds->fluidmat, VEC_INVARIANT, true, density_grid);
 		}
 
@@ -1104,25 +1104,25 @@ static int ptcache_smoke_openvdb_read(struct OpenVDBReader *reader, void *smoke_
 
 		OpenVDB_import_grid_fl(reader, "shadow", &sds->shadow, sds->res);
 
-		const char *name = (!sds->wt) ? "density" : "density low";
+		const char *name = (!sds->wt) ? "density" : "density_low";
 		OpenVDB_import_grid_fl(reader, name, &dens, sds->res);
 
 		if (cache_fields & SM_ACTIVE_HEAT) {
 			OpenVDB_import_grid_fl(reader, "heat", &heat, sds->res);
-			OpenVDB_import_grid_fl(reader, "heat old", &heatold, sds->res);
+			OpenVDB_import_grid_fl(reader, "heat_old", &heatold, sds->res);
 		}
 
 		if (cache_fields & SM_ACTIVE_FIRE) {
-			name = (!sds->wt) ? "flame" : "flame low";
+			name = (!sds->wt) ? "flame" : "flame_low";
 			OpenVDB_import_grid_fl(reader, name, &flame, sds->res);
-			name = (!sds->wt) ? "fuel" : "fuel low";
+			name = (!sds->wt) ? "fuel" : "fuel_low";
 			OpenVDB_import_grid_fl(reader, name, &fuel, sds->res);
-			name = (!sds->wt) ? "react" : "react low";
+			name = (!sds->wt) ? "react" : "react_low";
 			OpenVDB_import_grid_fl(reader, name, &react, sds->res);
 		}
 
 		if (cache_fields & SM_ACTIVE_COLORS) {
-			name = (!sds->wt) ? "color" : "color low";
+			name = (!sds->wt) ? "color" : "color_low";
 			OpenVDB_import_grid_vec(reader, name, &r, &g, &b, sds->res);
 		}