Cycles: Improved robustness of hair motion blur.motion_curve_fix

In some instances, the number of control vertices of a hair could change mid-frame.
Cycles would then be unable to calculate proper motion blur for those hairs. This adds
interpolated CVs to fill in for the missing data. While this will not necessarily result in
a fully accurate reconstruction of the guide hair, it preserves motion blur instead of disabling it.

Reviewers: #cycles, sergey

Reviewed By: #cycles, sergey

Subscribers: sergey, brecht, #cycles

Tags: #cycles

Differential Revision: https://developer.blender.org/D3695

1 files changed, 6 insertions, 6 deletions

diff --git a/source/blender/editors/gpencil/editaction_gpencil.c b/source/blender/editors/gpencil/editaction_gpencil.c
index 9d9ec51119b..3a3953579a6 100644
--- a/source/blender/editors/gpencil/editaction_gpencil.c
+++ b/source/blender/editors/gpencil/editaction_gpencil.c
@@ -308,10 +308,10 @@ void ED_gplayer_frames_keytype_set(bGPDlayer *gpl, short type)
 /* -------------------------------------- */
 /* Copy and Paste Tools */
 /* - The copy/paste buffer currently stores a set of GP_Layers, with temporary
- *	GP_Frames with the necessary strokes
+ *   GP_Frames with the necessary strokes
  * - Unless there is only one element in the buffer, names are also tested to check for compatibility.
  * - All pasted frames are offset by the same amount. This is calculated as the difference in the times of
- *	the current frame and the 'first keyframe' (i.e. the earliest one in all channels).
+ *   the current frame and the 'first keyframe' (i.e. the earliest one in all channels).
  * - The earliest frame is calculated per copy operation.
  */
 
@@ -483,10 +483,10 @@ bool ED_gpencil_anim_copybuf_paste(bAnimContext *ac, const short offset_mode)
 
 				/* This should be the right frame... as it may be a pre-existing frame,
 				 * must make sure that only compatible stroke types get copied over
-				 *	- We cannot just add a duplicate frame, as that would cause errors
-				 *  - For now, we don't check if the types will be compatible since we
-				 *    don't have enough info to do so. Instead, we simply just paste,
-				 *    af it works, it will show up.
+				 * - We cannot just add a duplicate frame, as that would cause errors
+				 * - For now, we don't check if the types will be compatible since we
+				 *   don't have enough info to do so. Instead, we simply just paste,
+				 *   if it works, it will show up.
 				 */
 				for (gps = gpfs->strokes.first; gps; gps = gps->next) {
 					/* make a copy of stroke, then of its points array */