Fix: Potential divide by 0 using GRAPH_OT_ease

In case there is only 1 key on the FCurve,
the operator can run into a situation where it divides by 0.
It now skips the curve in that case

Reviewed by: Sybren A. Stüvel
Differential Revision: https://developer.blender.org/D16982
Ref: D16982

release/datafiles/locale

@@ -1 +1 @@
-Subproject commit 7084c4ecd97d93459d9d23fd90f81589b09be5df
+Subproject commit 4f6dbb69893bd6bdf73467effe77ae46c8e4ee37

release/scripts/addons

@@ -1 +1 @@
-Subproject commit a9d4443c244f89399ec4bcc427e05a07950528cc
+Subproject commit bf49eeaa14c445d3c53068203fdf91bff568fe64

release/scripts/addons_contrib

@@ -1 +1 @@
-Subproject commit bdcfdd47ec3451822b21d1cff2ea2db751093c9a
+Subproject commit 0f72f6c85c3743a9072273acb6a8a34b1cf1064b

source/blender/editors/animation/keyframes_general.c

@@ -388,6 +388,12 @@ void ease_fcurve_segment(FCurve *fcu, FCurveSegment *segment, const float factor
   const float key_x_range = right_key.vec[1][0] - left_x;
   const float key_y_range = right_key.vec[1][1] - left_y;
 
+  /* Happens if there is only 1 key on the FCurve. Needs to be skipped because it
+   * would be a divide by 0. */
+  if (IS_EQF(key_x_range, 0.0f)) {
+    return;
+  }
+
   /* In order to have a curve that favors the right key, the curve needs to be mirrored in x and y.
    * Having an exponent that is a fraction of 1 would produce a similar but inferior result. */
   const bool inverted = factor > 0.5;

source/tools

@@ -1 +1 @@
-Subproject commit e1744b9bd82527cf7e8af63362b61bd309b5711b
+Subproject commit 3582f5326d08ca05c2a19056597e49ec5511d854