Subdiv: Make Blender crease to OSD sharpness reusable

Makes it so conversion is centralized in a single place.

We might consider removing any conversion, passing value as-is which
will be easier for I/O scripts to match crease. The downside of that
would be loose of control range in certain qualities and values of
crease.

There shouldn't be any functional changes in this commit.

1 files changed, 11 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/subdiv_inline.h b/source/blender/blenkernel/intern/subdiv_inline.h
index f00c5cf7ff7..a51a33feb3d 100644
--- a/source/blender/blenkernel/intern/subdiv_inline.h
+++ b/source/blender/blenkernel/intern/subdiv_inline.h
@@ -104,4 +104,15 @@ BLI_INLINE void BKE_subdiv_rotate_grid_to_quad(
   }
 }
 
+BLI_INLINE float BKE_subdiv_edge_crease_to_sharpness_f(float edge_crease)
+{
+  return edge_crease * edge_crease * 10.0f;
+}
+
+BLI_INLINE float BKE_subdiv_edge_crease_to_sharpness_char(char edge_crease)
+{
+  const float edge_crease_f = edge_crease / 255.0f;
+  return BKE_subdiv_edge_crease_to_sharpness_f(edge_crease_f);
+}
+
 #endif /* __SUBDIV_INLINE_H__ */