Optional clumping noise feature for simulating twisted hair strands.

This adds another level of clumping on child hairs. When enabled, child
hairs chose a secondary clumping target using a Voronoi pattern. This
adds visual detail on a smaller scale, which is useful particularly when
the number of parents is relatively small.

Natural fibres behave in a similar way when they become sticky and
intertwined. Hairs close to each other form a first twisted strand, then
combine into larger strands. Similar features can be found in ropes:
http://en.wikipedia.org/wiki/Hair_twists
http://en.wikipedia.org/wiki/Rope

Conflicts:
	source/blender/blenloader/intern/versioning_270.c

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/blenloader/intern/versioning_270.c b/source/blender/blenloader/intern/versioning_270.c
index 2261f311a23..38076f6348f 100644
--- a/source/blender/blenloader/intern/versioning_270.c
+++ b/source/blender/blenloader/intern/versioning_270.c
@@ -491,4 +491,11 @@ void blo_do_versions_270(FileData *fd, Library *UNUSED(lib), Main *main)
 			}
 		}
 	}
+
+	if (!DNA_struct_elem_find(fd->filesdna, "ParticleSettings", "float", "clumpnoisesize")) {
+		ParticleSettings *part;
+		for (part = main->particle.first; part; part = part->id.next) {
+			part->clump_noise_size = 1.0f;
+		}
+	}
 }