Fix T70281: Changing Default interpolation also changes curve of new drivers

Having a constant FCurve doesn't make sense for drivers; either linear
or Bezier should be used. Since the code is already creating a Bezier
curve, I just added the flag to not look at the user preferences in this
case.

Reviewed by: angavrilov

Differential Revision: https://developer.blender.org/D5921

1 files changed, 4 insertions, 8 deletions

diff --git a/source/blender/editors/animation/drivers.c b/source/blender/editors/animation/drivers.c
index e75dd92e90b..121683be407 100644
--- a/source/blender/editors/animation/drivers.c
+++ b/source/blender/editors/animation/drivers.c
@@ -139,14 +139,10 @@ struct FCurve *alloc_driver_fcurve(const char rna_path[],
        * - These are configured to 0,0 and 1,1 to give a 1-1 mapping
        *   which can be easily tweaked from there.
        */
-      insert_vert_fcurve(fcu, 0.0f, 0.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_FAST);
-      insert_vert_fcurve(fcu, 1.0f, 1.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_FAST);
-
-      /* configure this curve to extrapolate */
-      for (i = 0, bezt = fcu->bezt; (i < fcu->totvert) && bezt; i++, bezt++) {
-        bezt->h1 = bezt->h2 = HD_VECT;
-      }
-
+      insert_vert_fcurve(
+          fcu, 0.0f, 0.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_FAST | INSERTKEY_NO_USERPREF);
+      insert_vert_fcurve(
+          fcu, 1.0f, 1.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_FAST | INSERTKEY_NO_USERPREF);
       fcu->extend = FCURVE_EXTRAPOLATE_LINEAR;
       calchandles_fcurve(fcu);
     }