1 files changed, 62 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/volume.cc b/source/blender/blenkernel/intern/volume.cc
index 0c131863edd..307466d7dc9 100644
--- a/source/blender/blenkernel/intern/volume.cc
+++ b/source/blender/blenkernel/intern/volume.cc
@@ -60,6 +60,7 @@ using blender::float3;
 using blender::float4x4;
 using blender::IndexRange;
 using blender::StringRef;
+using blender::StringRefNull;
 
 #ifdef WITH_OPENVDB
 #  include <atomic>
@@ -517,6 +518,8 @@ static void volume_init_data(ID *id)
   MEMCPY_STRUCT_AFTER(volume, DNA_struct_default_get(Volume), id);
 
   BKE_volume_init_grids(volume);
+
+  BLI_strncpy(volume->velocity_grid, "velocity", sizeof(volume->velocity_grid));
 }
 
 static void volume_copy_data(Main *UNUSED(bmain),
@@ -794,6 +797,57 @@ bool BKE_volume_is_loaded(const Volume *volume)
 #endif
 }
 
+bool BKE_volume_set_velocity_grid_by_name(Volume *volume, const char *base_name)
+{
+  const StringRefNull ref_base_name = base_name;
+
+  if (BKE_volume_grid_find_for_read(volume, base_name)) {
+    BLI_strncpy(volume->velocity_grid, base_name, sizeof(volume->velocity_grid));
+    volume->runtime.velocity_x_grid[0] = '\0';
+    volume->runtime.velocity_y_grid[0] = '\0';
+    volume->runtime.velocity_z_grid[0] = '\0';
+    return true;
+  }
+
+  /* It could be that the velocity grid is split in multiple grids, try with known postfixes. */
+  const StringRefNull postfixes[][3] = {{"x", "y", "z"}, {".x", ".y", ".z"}, {"_x", "_y", "_z"}};
+
+  for (const StringRefNull *postfix : postfixes) {
+    bool found = true;
+    for (int i = 0; i < 3; i++) {
+      std::string post_fixed_name = ref_base_name + postfix[i];
+      if (!BKE_volume_grid_find_for_read(volume, post_fixed_name.c_str())) {
+        found = false;
+        break;
+      }
+    }
+
+    if (!found) {
+      continue;
+    }
+
+    /* Save the base name as well. */
+    BLI_strncpy(volume->velocity_grid, base_name, sizeof(volume->velocity_grid));
+    BLI_strncpy(volume->runtime.velocity_x_grid,
+                (ref_base_name + postfix[0]).c_str(),
+                sizeof(volume->runtime.velocity_x_grid));
+    BLI_strncpy(volume->runtime.velocity_y_grid,
+                (ref_base_name + postfix[1]).c_str(),
+                sizeof(volume->runtime.velocity_y_grid));
+    BLI_strncpy(volume->runtime.velocity_z_grid,
+                (ref_base_name + postfix[2]).c_str(),
+                sizeof(volume->runtime.velocity_z_grid));
+    return true;
+  }
+
+  /* Reset to avoid potential issues. */
+  volume->velocity_grid[0] = '\0';
+  volume->runtime.velocity_x_grid[0] = '\0';
+  volume->runtime.velocity_y_grid[0] = '\0';
+  volume->runtime.velocity_z_grid[0] = '\0';
+  return false;
+}
+
 bool BKE_volume_load(const Volume *volume, const Main *bmain)
 {
 #ifdef WITH_OPENVDB
@@ -857,6 +911,14 @@ bool BKE_volume_load(const Volume *volume, const Main *bmain)
     }
   }
 
+  /* Try to detect the velocity grid. */
+  const char *common_velocity_names[] = {"velocity", "vel", "v"};
+  for (const char *common_velocity_name : common_velocity_names) {
+    if (BKE_volume_set_velocity_grid_by_name(const_cast<Volume *>(volume), common_velocity_name)) {
+      break;
+    }
+  }
+
   BLI_strncpy(grids.filepath, filepath, FILE_MAX);
 
   return grids.error_msg.empty();