Added basic filtering feature for velocity smoothing.

This is part of the original method from "Volumetric Methods for
Simulation and Rendering of Hair". The current filter is a simple box
filter. Other energy-preserving filters such as gaussian filtering
can be implemented later.

The filter size is currently given as a cell count. This is not ideal,
rather it should use a geometrical length value, but this is too
abstract for proper artistical use. Eventually defining the whole grid
in terms of spatial size might work better (possibly using an external
object).

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_cloth.c b/source/blender/makesrna/intern/rna_cloth.c
index 8528a664458..eff194fcd5c 100644
--- a/source/blender/makesrna/intern/rna_cloth.c
+++ b/source/blender/makesrna/intern/rna_cloth.c
@@ -417,6 +417,13 @@ static void rna_def_cloth_sim_settings(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Voxel Grid Resolution", "Resolution of the voxel grid for interaction effects");
 	RNA_def_property_update(prop, 0, "rna_cloth_update");
 
+	prop = RNA_def_property(srna, "voxel_filter_size", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_int_sdna(prop, NULL, "voxel_filter_size");
+	RNA_def_property_range(prop, 0, 8);
+	RNA_def_property_int_default(prop, 0);
+	RNA_def_property_ui_text(prop, "Voxel Grid Filter Size", "Number of cells to use for filtering grid velocity");
+	RNA_def_property_update(prop, 0, "rna_cloth_update");
+
 	/* springs */
 
 	prop = RNA_def_property(srna, "use_stiffness_scale", PROP_BOOLEAN, PROP_NONE);