[Bf-docboard-svn] bf-manual: [9937] trunk/blender_docs/manual/animation/shape_keys/shape_keys_panel.rst: Document how the reference key of a relative shape key actually works.

[Alexander Gavrilov]

Revision: 9937
          https://developer.blender.org/rBM9937
Author:   angavrilov
Date:     2023-02-05 13:08:17 +0100 (Sun, 05 Feb 2023)
Log Message:
-----------
Document how the reference key of a relative shape key actually works.

Modified Paths:
--------------
    trunk/blender_docs/manual/animation/shape_keys/shape_keys_panel.rst

Modified: trunk/blender_docs/manual/animation/shape_keys/shape_keys_panel.rst
===================================================================
--- trunk/blender_docs/manual/animation/shape_keys/shape_keys_panel.rst	2023-02-04 02:07:23 UTC (rev 9936)
+++ trunk/blender_docs/manual/animation/shape_keys/shape_keys_panel.rst	2023-02-05 12:08:17 UTC (rev 9937)
@@ -161,7 +161,14 @@
 Relative To
    Select the shape key to deform from. This is called the *Reference Key* for that shape.
 
+.. note::
 
+   Rather than storing offsets directly, internally relative keys are stored as snapshots of the mesh shape.
+   The relative deformation offsets are computed by subtracting *Reference Key* from that snapshot.
+
+   Therefore, replacing the *Reference Key* has the effect of subtracting the difference between the new
+   and old reference from the relative deformation of the current key.
+
 Absolute Shape Keys
 ===================