Simple hair children: Initial implementation of twist control

It allows to have children hair to be twisted around parent curve, which is
quite an essential feature when creating hair braids.

There are currently two controls:

- Number of turns around parent children.
- Influence curve, which allows to modify "twistness" along the strand.

1 files changed, 6 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_ui/properties_particle.py b/release/scripts/startup/bl_ui/properties_particle.py
index b01d1ebbfa3..e552ff35ffa 100644
--- a/release/scripts/startup/bl_ui/properties_particle.py
+++ b/release/scripts/startup/bl_ui/properties_particle.py
@@ -1198,6 +1198,12 @@ class PARTICLE_PT_children(ParticleButtonsPanel, Panel):
         col.label(text="Effects:")
 
         sub = col.column(align=True)
+        if part.child_type == 'SIMPLE':
+            sub.prop(part, "twist")
+            sub.prop(part, "use_twist_curve")
+            if part.use_twist_curve:
+                sub.template_curve_mapping(part, "twist_curve")
+
         sub.prop(part, "use_clump_curve")
         if part.use_clump_curve:
             sub.template_curve_mapping(part, "clump_curve")