Dope Sheet: new option to display keyframe interpolation mode and extremes.

With the new automatic handle algorithm, it is possible to do a lot
of the animation via keyframes without touching the curves. It is
however necessary to change the keyframe interpolation and handle
types in certain cases. Currently the dopesheet/action editor
allows changing the types, but does not show them in any way.

To fix, add a new menu option to display this information. For handle
type, it is represented using the shape of the key icons: diamond for
Free, clipped diamond for Aligned, square for Vector, circle for Auto
Clamp, and cirle with dot for Automatic.

Non-bezier interpolation is a property of intervals between keys,
so it is marked by drawing lines, similar to holds. In this initial
version, only the fact of non-bezier interpolation is displayed,
without distinguishing types. For summaries, the line is drawn at
half alpha if not all curves in the group are non-bezier.

In addition, it is sometimes helpful to know the general direction
of change of the curve, and which keys are extremes. This commit
also adds an option to highlight extremes, based on comparing the
keyed values with adjacent keys. Half-intensity display is used
for overshot bezier extremes, or non-uniform summaries.

Reviewers: brecht, aligorith, billreynish

Differential Revision: https://developer.blender.org/D3788

1 files changed, 49 insertions, 17 deletions

diff --git a/source/blender/editors/include/ED_keyframes_draw.h b/source/blender/editors/include/ED_keyframes_draw.h
index 93fd8238fdd..6421c5817b0 100644
--- a/source/blender/editors/include/ED_keyframes_draw.h
+++ b/source/blender/editors/include/ED_keyframes_draw.h
@@ -73,6 +73,8 @@ typedef struct ActKeyColumn {
 
 	/* keyframe info */
 	char key_type;                      /* eBezTripe_KeyframeType */
+	char handle_type;                   /* eKeyframeHandleDrawOpts */
+	char extreme_type;                  /* eKeyframeExtremeDrawOpts */
 	short sel;
 	float cfra;
 
@@ -91,6 +93,8 @@ typedef enum eActKeyBlock_Hold {
 	ACTKEYBLOCK_FLAG_STATIC_HOLD     = (1 << 1),
 	/* Key block represents any kind of hold */
 	ACTKEYBLOCK_FLAG_ANY_HOLD        = (1 << 2),
+	/* The curve segment uses non-bezier interpolation */
+	ACTKEYBLOCK_FLAG_NON_BEZIER      = (1 << 3),
 } eActKeyBlock_Flag;
 
 /* *********************** Keyframe Drawing ****************************** */
@@ -105,48 +109,73 @@ typedef enum eKeyframeShapeDrawOpts {
 	KEYFRAME_SHAPE_BOTH
 } eKeyframeShapeDrawOpts;
 
+/* Handle type. */
+typedef enum eKeyframeHandleDrawOpts {
+	/* Don't draw */
+	KEYFRAME_HANDLE_NONE = 0,
+	/* Various marks in order of increasing display priority. */
+	KEYFRAME_HANDLE_AUTO_CLAMP,
+	KEYFRAME_HANDLE_AUTO,
+	KEYFRAME_HANDLE_VECTOR,
+	KEYFRAME_HANDLE_ALIGNED,
+	KEYFRAME_HANDLE_FREE,
+} eKeyframeHandleDrawOpts;
+
+/* Extreme type. */
+typedef enum eKeyframeExtremeDrawOpts {
+	KEYFRAME_EXTREME_NONE  = 0,
+	/* Minimum/maximum present. */
+	KEYFRAME_EXTREME_MIN   = (1 << 0),
+	KEYFRAME_EXTREME_MAX   = (1 << 1),
+	/* Grouped keys have different states. */
+	KEYFRAME_EXTREME_MIXED = (1 << 2),
+	/* Both neigbors are equal to this key. */
+	KEYFRAME_EXTREME_FLAT  = (1 << 3),
+} eKeyframeExtremeDrawOpts;
+
 /* draw simple diamond-shape keyframe */
 /* caller should set up vertex format, bind GPU_SHADER_KEYFRAME_DIAMOND, immBegin(GPU_PRIM_POINTS, n), then call this n times */
 void draw_keyframe_shape(float x, float y, float size, bool sel, short key_type, short mode, float alpha,
-                         unsigned int pos_id, unsigned int size_id, unsigned int color_id, unsigned int outline_color_id);
+                         unsigned int pos_id, unsigned int size_id, unsigned int color_id, unsigned int outline_color_id,
+                         unsigned int linemask_id, short ipo_type, short extreme_type);
 
 /* ******************************* Methods ****************************** */
 
 /* Channel Drawing ------------------ */
 /* F-Curve */
-void draw_fcurve_channel(struct View2D *v2d, struct AnimData *adt, struct FCurve *fcu, float ypos, float yscale_fac);
+void draw_fcurve_channel(struct View2D *v2d, struct AnimData *adt, struct FCurve *fcu, float ypos, float yscale_fac, int saction_flag);
 /* Action Group Summary */
-void draw_agroup_channel(struct View2D *v2d, struct AnimData *adt, struct bActionGroup *agrp, float ypos, float yscale_fac);
+void draw_agroup_channel(struct View2D *v2d, struct AnimData *adt, struct bActionGroup *agrp, float ypos, float yscale_fac, int saction_flag);
 /* Action Summary */
-void draw_action_channel(struct View2D *v2d, struct AnimData *adt, struct bAction *act, float ypos, float yscale_fac);
+void draw_action_channel(struct View2D *v2d, struct AnimData *adt, struct bAction *act, float ypos, float yscale_fac, int saction_flag);
 /* Object Summary */
-void draw_object_channel(struct View2D *v2d, struct bDopeSheet *ads, struct Object *ob, float ypos, float yscale_fac);
+void draw_object_channel(struct View2D *v2d, struct bDopeSheet *ads, struct Object *ob, float ypos, float yscale_fac, int saction_flag);
 /* Scene Summary */
-void draw_scene_channel(struct View2D *v2d, struct bDopeSheet *ads, struct Scene *sce, float ypos, float yscale_fac);
+void draw_scene_channel(struct View2D *v2d, struct bDopeSheet *ads, struct Scene *sce, float ypos, float yscale_fac, int saction_flag);
 /* DopeSheet Summary */
-void draw_summary_channel(struct View2D *v2d, struct bAnimContext *ac, float ypos, float yscale_fac);
+void draw_summary_channel(struct View2D *v2d, struct bAnimContext *ac, float ypos, float yscale_fac, int saction_flag);
 /* Grease Pencil datablock summary */
-void draw_gpencil_channel(struct View2D *v2d, struct bDopeSheet *ads, struct bGPdata *gpd, float ypos, float yscale_fac);
+void draw_gpencil_channel(struct View2D *v2d, struct bDopeSheet *ads, struct bGPdata *gpd, float ypos, float yscale_fac, int saction_flag);
 /* Grease Pencil Layer */
-void draw_gpl_channel(struct View2D *v2d, struct bDopeSheet *ads, struct bGPDlayer *gpl, float ypos, float yscale_fac);
+void draw_gpl_channel(struct View2D *v2d, struct bDopeSheet *ads, struct bGPDlayer *gpl, float ypos, float yscale_fac, int saction_flag);
 /* Mask Layer */
-void draw_masklay_channel(struct View2D *v2d, struct bDopeSheet *ads, struct MaskLayer *masklay, float ypos, float yscale_fac);
+void draw_masklay_channel(struct View2D *v2d, struct bDopeSheet *ads, struct MaskLayer *masklay, float ypos, float yscale_fac, int saction_flag);
 
 /* Keydata Generation --------------- */
 /* F-Curve */
-void fcurve_to_keylist(struct AnimData *adt, struct FCurve *fcu, struct DLRBT_Tree *keys);
+void fcurve_to_keylist(struct AnimData *adt, struct FCurve *fcu, struct DLRBT_Tree *keys, int saction_flag);
 /* Action Group */
-void agroup_to_keylist(struct AnimData *adt, struct bActionGroup *agrp, struct DLRBT_Tree *keys);
+void agroup_to_keylist(struct AnimData *adt, struct bActionGroup *agrp, struct DLRBT_Tree *keys, int saction_flag);
 /* Action */
-void action_to_keylist(struct AnimData *adt, struct bAction *act, struct DLRBT_Tree *keys);
+void action_to_keylist(struct AnimData *adt, struct bAction *act, struct DLRBT_Tree *keys, int saction_flag);
 /* Object */
-void ob_to_keylist(struct bDopeSheet *ads, struct Object *ob, struct DLRBT_Tree *keys);
+void ob_to_keylist(struct bDopeSheet *ads, struct Object *ob, struct DLRBT_Tree *keys, int saction_flag);
 /* Cache File */
-void cachefile_to_keylist(struct bDopeSheet *ads, struct CacheFile *cache_file, struct DLRBT_Tree *keys);
+void cachefile_to_keylist(struct bDopeSheet *ads, struct CacheFile *cache_file, struct DLRBT_Tree *keys, int saction_flag);
 /* Scene */
-void scene_to_keylist(struct bDopeSheet *ads, struct Scene *sce, struct DLRBT_Tree *keys);
+void scene_to_keylist(struct bDopeSheet *ads, struct Scene *sce, struct DLRBT_Tree *keys, int saction_flag);
 /* DopeSheet Summary */
-void summary_to_keylist(struct bAnimContext *ac, struct DLRBT_Tree *keys);
+void summary_to_keylist(struct bAnimContext *ac, struct DLRBT_Tree *keys, int saction_flag);
 /* Grease Pencil datablock summary */
 void gpencil_to_keylist(struct bDopeSheet *ads, struct bGPdata *gpd, struct DLRBT_Tree *keys, const bool active);
 /* Grease Pencil Layer */
@@ -160,6 +189,9 @@ void mask_to_keylist(struct bDopeSheet *UNUSED(ads), struct MaskLayer *masklay,
 /* Comparator callback used for ActKeyColumns and cframe float-value pointer */
 short compare_ak_cfraPtr(void *node, void *data);
 
+/* Checks if ActKeyColumn has any block data */
+bool actkeyblock_is_valid(ActKeyColumn *ab);
+
 /* Checks if ActKeyColumn can be used as a block (i.e. drawn/used to detect "holds") */
 int actkeyblock_get_valid_hold(ActKeyColumn *ab);