Fix T76595: Indicate the Active Keyframe in Graph Editor

In the graph editor there is a panel that says "Active Keyframe" for
numerically editing a keyframe's values, but in the code there is no
concept of the "active keyframe." Since this is a useful concept to
have for some other features anyway, this commit adds an active
keyframe index value to FCurves. It also displays it with a theme
color for the active vertex (which didn't exist before) if the
FCurve is active.

The active keyframe in the graph editor is treated similarly to the
active vertex in the 3D view. It is the keyframe most recently selected
with a single click, and it is always selected.

For now, the only real functional change is that the active keyframe
appears in white and it should be more predictable which keyframe is
being edited in the sidebar panel.

Differential Revision: https://developer.blender.org/D7737

1 files changed, 3 insertions, 2 deletions

diff --git a/source/blender/makesdna/DNA_userdef_types.h b/source/blender/makesdna/DNA_userdef_types.h
index f0a1378920e..c41a8bb9bc1 100644
--- a/source/blender/makesdna/DNA_userdef_types.h
+++ b/source/blender/makesdna/DNA_userdef_types.h
@@ -275,7 +275,8 @@ typedef struct ThemeSpace {
   unsigned char wire[4], wire_edit[4], select[4];
   unsigned char lamp[4], speaker[4], empty[4], camera[4];
   unsigned char active[4], group[4], group_active[4], transform[4];
-  unsigned char vertex[4], vertex_select[4], vertex_bevel[4], vertex_unreferenced[4];
+  unsigned char vertex[4], vertex_select[4], vertex_active[4], vertex_bevel[4],
+      vertex_unreferenced[4];
   unsigned char edge[4], edge_select[4];
   unsigned char edge_seam[4], edge_sharp[4], edge_facesel[4], edge_crease[4], edge_bevel[4];
   /** Solid faces. */
@@ -357,7 +358,7 @@ typedef struct ThemeSpace {
   unsigned char path_before[4], path_after[4];
   unsigned char path_keyframe_before[4], path_keyframe_after[4];
   unsigned char camera_path[4];
-  unsigned char _pad1[2];
+  unsigned char _pad1[6];
 
   unsigned char gp_vertex_size;
   unsigned char gp_vertex[4], gp_vertex_select[4];