Performance: Limit recounting during selection mode flushing.

This patch ensures that selection mode flushing updates total selection
counts internally. This reduces recounting when we are sure that the
input total selection counts were up to date.

For example for circle selection the total selection counts were
correct. But during flushing the selection could have been changed and
therefore the selection was always recounted.

This increased the performance on selected system from 6.90 FPS to 8.25
FPS during circle selection operations.

Before: {F10179981}
After: {F10179982}

Reviewed By: mano-wii

Differential Revision: https://developer.blender.org/D11647

2 files changed, 76 insertions, 44 deletions

diff --git a/source/blender/bmesh/intern/bmesh_marking.c b/source/blender/bmesh/intern/bmesh_marking.c
index d479a555a58..0bb86471cbd 100644
--- a/source/blender/bmesh/intern/bmesh_marking.c
+++ b/source/blender/bmesh/intern/bmesh_marking.c
@@ -40,31 +40,50 @@
 /* For '_FLAG_OVERLAP'. */
 #include "bmesh_private.h"
 
-static void recount_totsels(BMesh *bm)
+static int recount_totsel(BMesh *bm, BMIterType iter_type)
 {
-  const char iter_types[3] = {BM_VERTS_OF_MESH, BM_EDGES_OF_MESH, BM_FACES_OF_MESH};
-  int *tots[3];
-  int i;
-
-  /* Recount total selection variables. */
-  bm->totvertsel = bm->totedgesel = bm->totfacesel = 0;
-  tots[0] = &bm->totvertsel;
-  tots[1] = &bm->totedgesel;
-  tots[2] = &bm->totfacesel;
-
-  for (i = 0; i < 3; i++) {
-    BMIter iter;
-    BMElem *ele;
-    int count = 0;
+  BMIter iter;
+  BMElem *ele;
+  int count = 0;
 
-    BM_ITER_MESH (ele, &iter, bm, iter_types[i]) {
-      if (BM_elem_flag_test(ele, BM_ELEM_SELECT)) {
-        count += 1;
-      }
+  BM_ITER_MESH (ele, &iter, bm, iter_type) {
+    if (BM_elem_flag_test(ele, BM_ELEM_SELECT)) {
+      count += 1;
     }
-    *tots[i] = count;
   }
+  return count;
+}
+
+static void recount_totvertsel(BMesh *bm)
+{
+  bm->totvertsel = recount_totsel(bm, BM_VERTS_OF_MESH);
+}
+
+static void recount_totedgesel(BMesh *bm)
+{
+  bm->totedgesel = recount_totsel(bm, BM_EDGES_OF_MESH);
+}
+
+static void recount_totfacesel(BMesh *bm)
+{
+  bm->totfacesel = recount_totsel(bm, BM_FACES_OF_MESH);
+}
+
+static void recount_totsels(BMesh *bm)
+{
+  recount_totvertsel(bm);
+  recount_totedgesel(bm);
+  recount_totfacesel(bm);
+}
+
+#ifndef NDEBUG
+static bool recount_totsels_are_ok(BMesh *bm)
+{
+  return bm->totvertsel == recount_totsel(bm, BM_VERTS_OF_MESH) &&
+         bm->totedgesel == recount_totsel(bm, BM_EDGES_OF_MESH) &&
+         bm->totfacesel == recount_totsel(bm, BM_FACES_OF_MESH);
 }
+#endif
 
 /* -------------------------------------------------------------------- */
 /** \name BMesh helper functions for selection & hide flushing.
@@ -238,7 +257,7 @@ void BM_mesh_select_mode_clean(BMesh *bm)
  * (ie: all verts of an edge selects the edge and so on).
  * This should only be called by system and not tool authors.
  */
-void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode)
+void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode, eBMSelectionFlushFLags flags)
 {
   BMEdge *e;
   BMLoop *l_iter;
@@ -251,34 +270,22 @@ void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode)
   if (selectmode & SCE_SELECT_VERTEX) {
     /* both loops only set edge/face flags and read off verts */
     BM_ITER_MESH (e, &eiter, bm, BM_EDGES_OF_MESH) {
-      if (BM_elem_flag_test(e->v1, BM_ELEM_SELECT) && BM_elem_flag_test(e->v2, BM_ELEM_SELECT) &&
-          !BM_elem_flag_test(e, BM_ELEM_HIDDEN)) {
+      const bool is_selected = BM_elem_flag_test(e, BM_ELEM_SELECT);
+      if (!is_selected &&
+          (BM_elem_flag_test(e->v1, BM_ELEM_SELECT) && BM_elem_flag_test(e->v2, BM_ELEM_SELECT))) {
         BM_elem_flag_enable(e, BM_ELEM_SELECT);
+        bm->totedgesel += 1;
       }
       else {
         BM_elem_flag_disable(e, BM_ELEM_SELECT);
+        bm->totedgesel += is_selected ? -1 : 0;
       }
     }
-    BM_ITER_MESH (f, &fiter, bm, BM_FACES_OF_MESH) {
-      bool ok = true;
-      if (!BM_elem_flag_test(f, BM_ELEM_HIDDEN)) {
-        l_iter = l_first = BM_FACE_FIRST_LOOP(f);
-        do {
-          if (!BM_elem_flag_test(l_iter->v, BM_ELEM_SELECT)) {
-            ok = false;
-            break;
-          }
-        } while ((l_iter = l_iter->next) != l_first);
-      }
-      else {
-        ok = false;
-      }
-
-      BM_elem_flag_set(f, BM_ELEM_SELECT, ok);
-    }
   }
-  else if (selectmode & SCE_SELECT_EDGE) {
+
+  if (selectmode & (SCE_SELECT_VERTEX | SCE_SELECT_EDGE)) {
     BM_ITER_MESH (f, &fiter, bm, BM_FACES_OF_MESH) {
+      const bool is_selected = BM_elem_flag_test(f, BM_ELEM_SELECT);
       bool ok = true;
       if (!BM_elem_flag_test(f, BM_ELEM_HIDDEN)) {
         l_iter = l_first = BM_FACE_FIRST_LOOP(f);
@@ -294,18 +301,33 @@ void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode)
       }
 
       BM_elem_flag_set(f, BM_ELEM_SELECT, ok);
+      if (is_selected && !ok) {
+        bm->totfacesel -= 1;
+      }
+      else if (ok && !is_selected) {
+        bm->totfacesel += 1;
+      }
     }
   }
 
   /* Remove any deselected elements from the BMEditSelection */
   BM_select_history_validate(bm);
 
-  recount_totsels(bm);
+  if (flags & BM_SELECT_LEN_FLUSH_RECALC_VERT) {
+    recount_totvertsel(bm);
+  }
+  if (flags & BM_SELECT_LEN_FLUSH_RECALC_EDGE) {
+    recount_totedgesel(bm);
+  }
+  if (flags & BM_SELECT_LEN_FLUSH_RECALC_FACE) {
+    recount_totfacesel(bm);
+  }
+  BLI_assert(recount_totsels_are_ok(bm));
 }
 
 void BM_mesh_select_mode_flush(BMesh *bm)
 {
-  BM_mesh_select_mode_flush_ex(bm, bm->selectmode);
+  BM_mesh_select_mode_flush_ex(bm, bm->selectmode, BM_SELECT_LEN_FLUSH_RECALC_ALL);
 }
 
 /**
diff --git a/source/blender/bmesh/intern/bmesh_marking.h b/source/blender/bmesh/intern/bmesh_marking.h
index 04a49e24757..ff6c359138a 100644
--- a/source/blender/bmesh/intern/bmesh_marking.h
+++ b/source/blender/bmesh/intern/bmesh_marking.h
@@ -26,6 +26,16 @@ typedef struct BMEditSelection {
   char htype;
 } BMEditSelection;
 
+typedef enum eBMSelectionFlushFLags {
+  BM_SELECT_LEN_FLUSH_RECALC_NOTHING = 0,
+  BM_SELECT_LEN_FLUSH_RECALC_VERT = (1 << 0),
+  BM_SELECT_LEN_FLUSH_RECALC_EDGE = (1 << 1),
+  BM_SELECT_LEN_FLUSH_RECALC_FACE = (1 << 2),
+  BM_SELECT_LEN_FLUSH_RECALC_ALL = (BM_SELECT_LEN_FLUSH_RECALC_VERT |
+                                    BM_SELECT_LEN_FLUSH_RECALC_EDGE |
+                                    BM_SELECT_LEN_FLUSH_RECALC_FACE),
+} eBMSelectionFlushFLags;
+
 /* geometry hiding code */
 #define BM_elem_hide_set(bm, ele, hide) _bm_elem_hide_set(bm, &(ele)->head, hide)
 void _bm_elem_hide_set(BMesh *bm, BMHeader *head, const bool hide);
@@ -72,7 +82,7 @@ void BM_mesh_select_mode_clean_ex(BMesh *bm, const short selectmode);
 void BM_mesh_select_mode_clean(BMesh *bm);
 
 void BM_mesh_select_mode_set(BMesh *bm, int selectmode);
-void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode);
+void BM_mesh_select_mode_flush_ex(BMesh *bm, const short selectmode, eBMSelectionFlushFLags flags);
 void BM_mesh_select_mode_flush(BMesh *bm);
 
 void BM_mesh_deselect_flush(BMesh *bm);