scripts/startup/bl_ui/space_graph.py

@@ -324,6 +324,7 @@ class GRAPH_MT_key_blending(Menu):
         layout.operator("graph.blend_offset", text="Blend Offset")
         layout.operator("graph.blend_to_ease", text="Blend to Ease")
         layout.operator("graph.match_slope", text="Match Slope")
+        layout.operator("graph.push_pull", text="Push Pull")
         layout.operator("graph.shear", text="Shear Keys")
         layout.operator("graph.scale_average", text="Scale Average")
 

source/blender/editors/animation/keyframes_general.cc

@@ -881,6 +881,35 @@ void shear_fcurve_segment(FCurve *fcu,
 
 /* ---------------- */
 
+void push_pull_fcurve_segment(FCurve *fcu, FCurveSegment *segment, const float factor)
+{
+  const BezTriple *left_key = fcurve_segment_start_get(fcu, segment->start_index);
+  const BezTriple *right_key = fcurve_segment_end_get(fcu, segment->start_index + segment->length);
+
+  const float key_x_range = right_key->vec[1][0] - left_key->vec[1][0];
+  const float key_y_range = right_key->vec[1][1] - left_key->vec[1][1];
+
+  /* Happens if there is only 1 key on the FCurve. Needs to be skipped because it
+   * would be a divide by 0. */
+  if (IS_EQF(key_x_range, 0.0f)) {
+    return;
+  }
+
+  for (int i = segment->start_index; i < segment->start_index + segment->length; i++) {
+    /* For easy calculation of the curve, the values are normalized. */
+    const float normalized_x = (fcu->bezt[i].vec[1][0] - left_key->vec[1][0]) / key_x_range;
+
+    const float linear = left_key->vec[1][1] + key_y_range * normalized_x;
+
+    const float delta = fcu->bezt[i].vec[1][1] - linear;
+
+    const float key_y_value = linear + delta * factor;
+    BKE_fcurve_keyframe_move_value_with_handles(&fcu->bezt[i], key_y_value);
+  }
+}
+
+/* ---------------- */
+
 void breakdown_fcurve_segment(FCurve *fcu, FCurveSegment *segment, const float factor)
 {
   const BezTriple *left_bezt = fcurve_segment_start_get(fcu, segment->start_index);

source/blender/editors/include/ED_keyframes_edit.hh

@@ -431,7 +431,7 @@ void clean_fcurve(bAnimContext *ac, bAnimListElem *ale, float thresh, bool clear
 void blend_to_neighbor_fcurve_segment(FCurve *fcu, FCurveSegment *segment, float factor);
 void breakdown_fcurve_segment(FCurve *fcu, FCurveSegment *segment, float factor);
 void scale_average_fcurve_segment(struct FCurve *fcu, struct FCurveSegment *segment, float factor);
-
+void push_pull_fcurve_segment(struct FCurve *fcu, struct FCurveSegment *segment, float factor);
 /**
  * Get a 1D gauss kernel. Since the kernel is symmetrical, only calculates the positive side.
  * \param sigma: The shape of the gauss distribution.

source/blender/editors/space_graph/graph_intern.h

@@ -124,6 +124,7 @@ void GRAPH_OT_blend_to_ease(struct wmOperatorType *ot);
 void GRAPH_OT_match_slope(struct wmOperatorType *ot);
 void GRAPH_OT_shear(struct wmOperatorType *ot);
 void GRAPH_OT_scale_average(struct wmOperatorType *ot);
+void GRAPH_OT_push_pull(struct wmOperatorType *ot);
 void GRAPH_OT_decimate(struct wmOperatorType *ot);
 void GRAPH_OT_blend_to_default(struct wmOperatorType *ot);
 void GRAPH_OT_butterworth_smooth(struct wmOperatorType *ot);

source/blender/editors/space_graph/graph_ops.cc

@@ -475,6 +475,7 @@ void graphedit_operatortypes()
   WM_operatortype_append(GRAPH_OT_blend_to_ease);
   WM_operatortype_append(GRAPH_OT_match_slope);
   WM_operatortype_append(GRAPH_OT_blend_to_default);
+  WM_operatortype_append(GRAPH_OT_push_pull);
   WM_operatortype_append(GRAPH_OT_gaussian_smooth);
   WM_operatortype_append(GRAPH_OT_butterworth_smooth);
   WM_operatortype_append(GRAPH_OT_euler_filter);

source/blender/editors/space_graph/graph_slider_ops.cc

@@ -2075,3 +2075,90 @@ void GRAPH_OT_butterworth_smooth(wmOperatorType *ot)
               128);
 }
 /** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Push-Pull Operator
+ * \{ */
+
+static void push_pull_graph_keys(bAnimContext *ac, const float factor)
+{
+  apply_fcu_segment_function(ac, factor, push_pull_fcurve_segment);
+}
+
+static void push_pull_modal_update(bContext *C, wmOperator *op)
+{
+  tGraphSliderOp *gso = static_cast<tGraphSliderOp *>(op->customdata);
+
+  common_draw_status_header(C, gso, "Push Pull Keys");
+
+  /* Reset keyframes to the state at invoke. */
+  reset_bezts(gso);
+  const float factor = slider_factor_get_and_remember(op);
+  push_pull_graph_keys(&gso->ac, factor);
+  WM_event_add_notifier(C, NC_ANIMATION | ND_KEYFRAME | NA_EDITED, NULL);
+}
+
+static int push_pull_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  const int invoke_result = graph_slider_invoke(C, op, event);
+
+  if (invoke_result == OPERATOR_CANCELLED) {
+    return invoke_result;
+  }
+
+  tGraphSliderOp *gso = static_cast<tGraphSliderOp *>(op->customdata);
+  gso->modal_update = push_pull_modal_update;
+  gso->factor_prop = RNA_struct_find_property(op->ptr, "factor");
+  ED_slider_factor_bounds_set(gso->slider, 0, 2);
+  ED_slider_factor_set(gso->slider, 1);
+  common_draw_status_header(C, gso, "Push Pull Keys");
+
+  return invoke_result;
+}
+
+static int push_pull_exec(bContext *C, wmOperator *op)
+{
+  bAnimContext ac;
+
+  /* Get editor data. */
+  if (ANIM_animdata_get_context(C, &ac) == 0) {
+    return OPERATOR_CANCELLED;
+  }
+
+  const float factor = RNA_float_get(op->ptr, "factor");
+
+  push_pull_graph_keys(&ac, factor);
+
+  /* Set notifier that keyframes have changed. */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_KEYFRAME | NA_EDITED, NULL);
+
+  return OPERATOR_FINISHED;
+}
+
+void GRAPH_OT_push_pull(wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Push Pull Keyframes";
+  ot->idname = "GRAPH_OT_push_pull";
+  ot->description = "Exaggerate or minimize the value of the selected keys";
+
+  /* API callbacks. */
+  ot->invoke = push_pull_invoke;
+  ot->modal = graph_slider_modal;
+  ot->exec = push_pull_exec;
+  ot->poll = graphop_editable_keyframes_poll;
+
+  /* Flags. */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_BLOCKING | OPTYPE_GRAB_CURSOR_X;
+
+  RNA_def_float_factor(ot->srna,
+                       "factor",
+                       1.0f,
+                       -FLT_MAX,
+                       FLT_MAX,
+                       "Factor",
+                       "Control how far to push or pull the keys",
+                       0.0f,
+                       2.0f);
+}
+/** \} */