Fluid: Updated Mantaflow source files

This update introduces two improvements from the Mantaflow repository:

(1) Improved particle sampling:
- Liquid and secondary particles are sampled more predictably. With all parameters being equal, baked particles will be computed at the exact same position during every bake.
- Before, this was not guaranteed.

(2) Sparse grid caching:
- While saving grid data to disk, grids will from now on be saved in a sparse structure whenever possible (e.g. density, flame but not levelsets).
- With the sparse optimization grid cells with a value under the 'Empty Space' value (already present in domain settings) will not be cached.
- The main benefits of this optimization are: Smaller cache sizes and faster playback of simulation data in the viewport.
- This optimization works 'out-of-the-box'. There is no option in the UI to enable it.
- For now, only smoke simulation grids will take advantage of this optimization.

1 files changed, 3 insertions, 1 deletions

diff --git a/extern/mantaflow/preprocessed/fileio/mantaio.h b/extern/mantaflow/preprocessed/fileio/mantaio.h
index d49f4b1369d..088d43556e1 100644
--- a/extern/mantaflow/preprocessed/fileio/mantaio.h
+++ b/extern/mantaflow/preprocessed/fileio/mantaio.h
@@ -75,7 +75,9 @@ int writeObjectsVDB(const std::string &filename,
                     float scale = 1.0,
                     bool skipDeletedParts = false,
                     int compression = COMPRESSION_ZIP,
-                    int precision = PRECISION_HALF);
+                    int precision = PRECISION_HALF,
+                    float clip = 1e-4,
+                    const Grid<Real> *clipGrid = nullptr);
 int readObjectsVDB(const std::string &filename,
                    std::vector<PbClass *> *objects,
                    float scale = 1.0);