Move fcurve cleanup from transform system to BKE

This exposes the fcurve cleanup from transform system to other callers
in anticipation to use it in the snapping operators.

It has been renamed from `posttrans_fcurve_clean` to
`BKE_fcurve_merge_duplicate_keys` to better describe what it does.
No functional change expected.

Ref. T101996

NOTE: same probably has to be done for greasepencil, but that is for
another commit.

Maniphest Tasks: T101996

Differential Revision: https://developer.blender.org/D16663

source/blender/blenkernel/BKE_fcurve.h

@@ -483,6 +483,18 @@ bool BKE_fcurve_delete_keys_selected(struct FCurve *fcu);
  */
 void BKE_fcurve_delete_keys_all(struct FCurve *fcu);
 
+/**
+ * Called during transform/snapping to make sure selected keyframes replace
+ * any other keyframes which may reside on that frame (that is not selected).
+ *
+ * \param sel_flag: The flag (bezt.f1/2/3) value to use to determine selection. Usually `SELECT`,
+ *                  but may want to use a different one at times (if caller does not operate on
+ *                  selection).
+ */
+void BKE_fcurve_merge_duplicate_keys(struct FCurve *fcu,
+                                     const int sel_flag,
+                                     const bool use_handle);
+
 /* -------- Curve Sanity -------- */
 
 /**

source/blender/blenkernel/intern/fcurve.c

@@ -1709,6 +1709,133 @@ void BKE_fcurve_delete_keys_all(FCurve *fcu)
   fcurve_bezt_free(fcu);
 }
 
+/* Time + Average value */
+typedef struct tRetainedKeyframe {
+  struct tRetainedKeyframe *next, *prev;
+  float frame; /* frame to cluster around */
+  float val;   /* average value */
+
+  size_t tot_count; /* number of keyframes that have been averaged */
+  size_t del_count; /* number of keyframes of this sort that have been deleted so far */
+} tRetainedKeyframe;
+
+void BKE_fcurve_merge_duplicate_keys(FCurve *fcu, const int sel_flag, const bool use_handle)
+{
+  /* NOTE: We assume that all keys are sorted */
+  ListBase retained_keys = {NULL, NULL};
+  const bool can_average_points = ((fcu->flag & (FCURVE_INT_VALUES | FCURVE_DISCRETE_VALUES)) ==
+                                   0);
+
+  /* sanity checks */
+  if ((fcu->totvert == 0) || (fcu->bezt == NULL)) {
+    return;
+  }
+
+  /* 1) Identify selected keyframes, and average the values on those
+   * in case there are collisions due to multiple keys getting scaled
+   * to all end up on the same frame
+   */
+  for (int i = 0; i < fcu->totvert; i++) {
+    BezTriple *bezt = &fcu->bezt[i];
+
+    if (BEZT_ISSEL_ANY(bezt)) {
+      bool found = false;
+
+      /* If there's another selected frame here, merge it */
+      for (tRetainedKeyframe *rk = retained_keys.last; rk; rk = rk->prev) {
+        if (IS_EQT(rk->frame, bezt->vec[1][0], BEZT_BINARYSEARCH_THRESH)) {
+          rk->val += bezt->vec[1][1];
+          rk->tot_count++;
+
+          found = true;
+          break;
+        }
+        if (rk->frame < bezt->vec[1][0]) {
+          /* Terminate early if have passed the supposed insertion point? */
+          break;
+        }
+      }
+
+      /* If nothing found yet, create a new one */
+      if (found == false) {
+        tRetainedKeyframe *rk = MEM_callocN(sizeof(tRetainedKeyframe), "tRetainedKeyframe");
+
+        rk->frame = bezt->vec[1][0];
+        rk->val = bezt->vec[1][1];
+        rk->tot_count = 1;
+
+        BLI_addtail(&retained_keys, rk);
+      }
+    }
+  }
+
+  if (BLI_listbase_is_empty(&retained_keys)) {
+    /* This may happen if none of the points were selected... */
+    if (G.debug & G_DEBUG) {
+      printf("%s: nothing to do for FCurve %p (rna_path = '%s')\n", __func__, fcu, fcu->rna_path);
+    }
+    return;
+  }
+
+  /* Compute the average values for each retained keyframe */
+  LISTBASE_FOREACH (tRetainedKeyframe *, rk, &retained_keys) {
+    rk->val = rk->val / (float)rk->tot_count;
+  }
+
+  /* 2) Delete all keyframes duplicating the "retained keys" found above
+   *   - Most of these will be unselected keyframes
+   *   - Some will be selected keyframes though. For those, we only keep the last one
+   *     (or else everything is gone), and replace its value with the averaged value.
+   */
+  for (int i = fcu->totvert - 1; i >= 0; i--) {
+    BezTriple *bezt = &fcu->bezt[i];
+
+    /* Is this keyframe a candidate for deletion? */
+    /* TODO: Replace loop with an O(1) lookup instead */
+    for (tRetainedKeyframe *rk = retained_keys.last; rk; rk = rk->prev) {
+      if (IS_EQT(bezt->vec[1][0], rk->frame, BEZT_BINARYSEARCH_THRESH)) {
+        /* Selected keys are treated with greater care than unselected ones... */
+        if (BEZT_ISSEL_ANY(bezt)) {
+          /* - If this is the last selected key left (based on rk->del_count) ==> UPDATE IT
+           *   (or else we wouldn't have any keyframe left here)
+           * - Otherwise, there are still other selected keyframes on this frame
+           *   to be merged down still ==> DELETE IT
+           */
+          if (rk->del_count == rk->tot_count - 1) {
+            /* Update keyframe... */
+            if (can_average_points) {
+              /* TODO: update handles too? */
+              bezt->vec[1][1] = rk->val;
+            }
+          }
+          else {
+            /* Delete Keyframe */
+            BKE_fcurve_delete_key(fcu, i);
+          }
+
+          /* Update count of how many we've deleted
+           * - It should only matter that we're doing this for all but the last one
+           */
+          rk->del_count++;
+        }
+        else {
+          /* Always delete - Unselected keys don't matter */
+          BKE_fcurve_delete_key(fcu, i);
+        }
+
+        /* Stop the RK search... we've found our match now */
+        break;
+      }
+    }
+  }
+
+  /* 3) Recalculate handles */
+  testhandles_fcurve(fcu, sel_flag, use_handle);
+
+  /* cleanup */
+  BLI_freelistN(&retained_keys);
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */

source/blender/editors/transform/transform_convert.c

@@ -538,139 +538,6 @@ bool FrameOnMouseSide(char side, float frame, float cframe)
 
 /** \} */
 
-/* -------------------------------------------------------------------- */
-/** \name Animation Editor
- * \{ */
-
-/* Time + Average value */
-typedef struct tRetainedKeyframe {
-  struct tRetainedKeyframe *next, *prev;
-  float frame; /* frame to cluster around */
-  float val;   /* average value */
-
-  size_t tot_count; /* number of keyframes that have been averaged */
-  size_t del_count; /* number of keyframes of this sort that have been deleted so far */
-} tRetainedKeyframe;
-
-void posttrans_fcurve_clean(FCurve *fcu, const int sel_flag, const bool use_handle)
-{
-  /* NOTE: We assume that all keys are sorted */
-  ListBase retained_keys = {NULL, NULL};
-  const bool can_average_points = ((fcu->flag & (FCURVE_INT_VALUES | FCURVE_DISCRETE_VALUES)) ==
-                                   0);
-
-  /* sanity checks */
-  if ((fcu->totvert == 0) || (fcu->bezt == NULL)) {
-    return;
-  }
-
-  /* 1) Identify selected keyframes, and average the values on those
-   * in case there are collisions due to multiple keys getting scaled
-   * to all end up on the same frame
-   */
-  for (int i = 0; i < fcu->totvert; i++) {
-    BezTriple *bezt = &fcu->bezt[i];
-
-    if (BEZT_ISSEL_ANY(bezt)) {
-      bool found = false;
-
-      /* If there's another selected frame here, merge it */
-      for (tRetainedKeyframe *rk = retained_keys.last; rk; rk = rk->prev) {
-        if (IS_EQT(rk->frame, bezt->vec[1][0], BEZT_BINARYSEARCH_THRESH)) {
-          rk->val += bezt->vec[1][1];
-          rk->tot_count++;
-
-          found = true;
-          break;
-        }
-        if (rk->frame < bezt->vec[1][0]) {
-          /* Terminate early if have passed the supposed insertion point? */
-          break;
-        }
-      }
-
-      /* If nothing found yet, create a new one */
-      if (found == false) {
-        tRetainedKeyframe *rk = MEM_callocN(sizeof(tRetainedKeyframe), "tRetainedKeyframe");
-
-        rk->frame = bezt->vec[1][0];
-        rk->val = bezt->vec[1][1];
-        rk->tot_count = 1;
-
-        BLI_addtail(&retained_keys, rk);
-      }
-    }
-  }
-
-  if (BLI_listbase_is_empty(&retained_keys)) {
-    /* This may happen if none of the points were selected... */
-    if (G.debug & G_DEBUG) {
-      printf("%s: nothing to do for FCurve %p (rna_path = '%s')\n", __func__, fcu, fcu->rna_path);
-    }
-    return;
-  }
-
-  /* Compute the average values for each retained keyframe */
-  LISTBASE_FOREACH (tRetainedKeyframe *, rk, &retained_keys) {
-    rk->val = rk->val / (float)rk->tot_count;
-  }
-
-  /* 2) Delete all keyframes duplicating the "retained keys" found above
-   *   - Most of these will be unselected keyframes
-   *   - Some will be selected keyframes though. For those, we only keep the last one
-   *     (or else everything is gone), and replace its value with the averaged value.
-   */
-  for (int i = fcu->totvert - 1; i >= 0; i--) {
-    BezTriple *bezt = &fcu->bezt[i];
-
-    /* Is this keyframe a candidate for deletion? */
-    /* TODO: Replace loop with an O(1) lookup instead */
-    for (tRetainedKeyframe *rk = retained_keys.last; rk; rk = rk->prev) {
-      if (IS_EQT(bezt->vec[1][0], rk->frame, BEZT_BINARYSEARCH_THRESH)) {
-        /* Selected keys are treated with greater care than unselected ones... */
-        if (BEZT_ISSEL_ANY(bezt)) {
-          /* - If this is the last selected key left (based on rk->del_count) ==> UPDATE IT
-           *   (or else we wouldn't have any keyframe left here)
-           * - Otherwise, there are still other selected keyframes on this frame
-           *   to be merged down still ==> DELETE IT
-           */
-          if (rk->del_count == rk->tot_count - 1) {
-            /* Update keyframe... */
-            if (can_average_points) {
-              /* TODO: update handles too? */
-              bezt->vec[1][1] = rk->val;
-            }
-          }
-          else {
-            /* Delete Keyframe */
-            BKE_fcurve_delete_key(fcu, i);
-          }
-
-          /* Update count of how many we've deleted
-           * - It should only matter that we're doing this for all but the last one
-           */
-          rk->del_count++;
-        }
-        else {
-          /* Always delete - Unselected keys don't matter */
-          BKE_fcurve_delete_key(fcu, i);
-        }
-
-        /* Stop the RK search... we've found our match now */
-        break;
-      }
-    }
-  }
-
-  /* 3) Recalculate handles */
-  testhandles_fcurve(fcu, sel_flag, use_handle);
-
-  /* cleanup */
-  BLI_freelistN(&retained_keys);
-}
-
-/** \} */
-
 /* -------------------------------------------------------------------- */
 /** \name Transform Utilities
  * \{ */

source/blender/editors/transform/transform_convert.h

@@ -83,15 +83,6 @@ bool transform_mode_use_local_origins(const TransInfo *t);
  */
 void transform_around_single_fallback_ex(TransInfo *t, int data_len_all);
 void transform_around_single_fallback(TransInfo *t);
-/**
- * Called during special_aftertrans_update to make sure selected keyframes replace
- * any other keyframes which may reside on that frame (that is not selected).
- *
- * \param sel_flag: The flag (bezt.f1/2/3) value to use to determine selection. Usually `SELECT`,
- *                  but may want to use a different one at times (if caller does not operate on
- *                  selection).
- */
-void posttrans_fcurve_clean(struct FCurve *fcu, int sel_flag, bool use_handle);
 /**
  * Little helper function for ObjectToTransData used to give certain
  * constraints (ChildOf, FollowPath, and others that may be added)

source/blender/editors/transform/transform_convert_action.c

@@ -16,6 +16,7 @@
 #include "BLI_rect.h"
 
 #include "BKE_context.h"
+#include "BKE_fcurve.h"
 #include "BKE_gpencil.h"
 #include "BKE_key.h"
 #include "BKE_layer.h"
@@ -750,11 +751,13 @@ static void posttrans_action_clean(bAnimContext *ac, bAction *act)
 
     if (adt) {
       ANIM_nla_mapping_apply_fcurve(adt, ale->key_data, 0, 0);
-      posttrans_fcurve_clean(ale->key_data, SELECT, false); /* only use handles in graph editor */
+      BKE_fcurve_merge_duplicate_keys(
+          ale->key_data, SELECT, false); /* only use handles in graph editor */
       ANIM_nla_mapping_apply_fcurve(adt, ale->key_data, 1, 0);
     }
     else {
-      posttrans_fcurve_clean(ale->key_data, SELECT, false); /* only use handles in graph editor */
+      BKE_fcurve_merge_duplicate_keys(
+          ale->key_data, SELECT, false); /* only use handles in graph editor */
     }
   }
 
@@ -806,11 +809,13 @@ static void special_aftertrans_update__actedit(bContext *C, TransInfo *t)
           if ((saction->flag & SACTION_NOTRANSKEYCULL) == 0 && ((canceled == 0) || (duplicate))) {
             if (adt) {
               ANIM_nla_mapping_apply_fcurve(adt, fcu, 0, 0);
-              posttrans_fcurve_clean(fcu, SELECT, false); /* only use handles in graph editor */
+              BKE_fcurve_merge_duplicate_keys(
+                  fcu, SELECT, false); /* only use handles in graph editor */
               ANIM_nla_mapping_apply_fcurve(adt, fcu, 1, 0);
             }
             else {
-              posttrans_fcurve_clean(fcu, SELECT, false); /* only use handles in graph editor */
+              BKE_fcurve_merge_duplicate_keys(
+                  fcu, SELECT, false); /* only use handles in graph editor */
             }
           }
           break;

source/blender/editors/transform/transform_convert_graph.c

@@ -1009,11 +1009,11 @@ static void special_aftertrans_update__graph(bContext *C, TransInfo *t)
       if ((sipo->flag & SIPO_NOTRANSKEYCULL) == 0 && ((canceled == 0) || (duplicate))) {
         if (adt) {
           ANIM_nla_mapping_apply_fcurve(adt, fcu, 0, 0);
-          posttrans_fcurve_clean(fcu, BEZT_FLAG_TEMP_TAG, use_handle);
+          BKE_fcurve_merge_duplicate_keys(fcu, BEZT_FLAG_TEMP_TAG, use_handle);
           ANIM_nla_mapping_apply_fcurve(adt, fcu, 1, 0);
         }
         else {
-          posttrans_fcurve_clean(fcu, BEZT_FLAG_TEMP_TAG, use_handle);
+          BKE_fcurve_merge_duplicate_keys(fcu, BEZT_FLAG_TEMP_TAG, use_handle);
         }
       }
     }