Fix Frame Dropping not dropping the correct amount of frames

Previously the playback mode "Frame Dropping" would not drop the correct
number of frames which would lead to slow playback.

For example, the playback target is 60fps.  However we can only muster
around 32 fps.

The delta frames from the last step is in this case ~1.98 or so.

With the previous code, we would floor this.  That would lead us to step
forward one frame each time, effectively playing back the animation at
half the speed as we will try to render every frame.

To fix this we simply save the remaining fraction from the previous
frame and use it to compute the current frame step.

Reviewed By: Sybren

Differential Revision: http://developer.blender.org/D7694

1 files changed, 5 insertions, 5 deletions

diff --git a/source/blender/editors/include/ED_screen_types.h b/source/blender/editors/include/ED_screen_types.h
index 06c2c3039f5..51f3eea74fa 100644
--- a/source/blender/editors/include/ED_screen_types.h
+++ b/source/blender/editors/include/ED_screen_types.h
@@ -34,11 +34,11 @@ extern "C" {
 typedef struct ScreenAnimData {
   ARegion *region; /* do not read from this, only for comparing if region exists */
   short redraws;
-  short flag;           /* flags for playback */
-  int sfra;             /* frame that playback was started from */
-  int nextfra;          /* next frame to go to (when ANIMPLAY_FLAG_USE_NEXT_FRAME is set) */
-  double last_duration; /* used for frame dropping */
-  bool from_anim_edit;  /* playback was invoked from animation editor */
+  short flag;                 /* flags for playback */
+  int sfra;                   /* frame that playback was started from */
+  int nextfra;                /* next frame to go to (when ANIMPLAY_FLAG_USE_NEXT_FRAME is set) */
+  double lagging_frame_count; /* used for frame dropping */
+  bool from_anim_edit;        /* playback was invoked from animation editor */
 } ScreenAnimData;
 
 /* for animplayer */