Cleanup: Minimize seq->tmp usage

Using this persistent field in `select_more_less_seq__internal` was
inapropriate in this case.

Split select more/less and linked code, because it was mixed in
`select_more_less_seq__internal()`
These operators work in completely different way.
`select_linked_internal()` doesn't use seq->tmp at all.

`seq->tmp` was used to mask strips selected by operator while iterating.
Use GSet to store temporary data instead of `seq->tmp`.

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D10326

source/blender/editors/space_sequencer/sequencer_select.c

@@ -26,6 +26,7 @@
 #include <string.h>
 
 #include "BLI_blenlib.h"
+#include "BLI_ghash.h"
 #include "BLI_math.h"
 #include "BLI_utildefines.h"
 
@@ -771,69 +772,83 @@ void SEQUENCER_OT_select(wmOperatorType *ot)
  * \{ */
 
 /* Run recursively to select linked. */
-static bool select_more_less_seq__internal(Scene *scene, bool sel, const bool linked)
+static bool select_linked_internal(Scene *scene)
 {
   Editing *ed = SEQ_editing_get(scene, false);
-  Sequence *seq, *neighbor;
-  bool changed = false;
-  int isel;
 
   if (ed == NULL) {
-    return changed;
+    return false;
   }
 
-  if (sel) {
-    sel = SELECT;
-    isel = 0;
-  }
-  else {
-    sel = 0;
-    isel = SELECT;
-  }
+  bool changed = false;
 
-  if (!linked) {
-    /* If not linked we only want to touch each seq once, newseq. */
-    for (seq = ed->seqbasep->first; seq; seq = seq->next) {
-      seq->tmp = NULL;
+  LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
+    if ((seq->flag & SELECT) != 0) {
+      continue;
+    }
+    /* Only get unselected neighbors. */
+    Sequence *neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_LEFT, 0);
+    if (neighbor) {
+      neighbor->flag |= SELECT;
+      recurs_sel_seq(neighbor);
+      changed = true;
+    }
+    neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, 0);
+    if (neighbor) {
+      neighbor->flag |= SELECT;
+      recurs_sel_seq(neighbor);
+      changed = true;
     }
   }
 
-  for (seq = ed->seqbasep->first; seq; seq = seq->next) {
-    if ((seq->flag & SELECT) == sel) {
-      if (linked || (seq->tmp == NULL)) {
-        /* Only get unselected neighbors. */
-        neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_LEFT, isel);
-        if (neighbor) {
-          if (sel) {
-            neighbor->flag |= SELECT;
-            recurs_sel_seq(neighbor);
-          }
-          else {
-            neighbor->flag &= ~SELECT;
-          }
-          if (!linked) {
-            neighbor->tmp = (Sequence *)1;
-          }
-          changed = true;
-        }
-        neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, isel);
-        if (neighbor) {
-          if (sel) {
-            neighbor->flag |= SELECT;
-            recurs_sel_seq(neighbor);
-          }
-          else {
-            neighbor->flag &= ~SELECT;
-          }
-          if (!linked) {
-            neighbor->tmp = (Sequence *)1;
-          }
-          changed = true;
-        }
-      }
+  return changed;
+}
+
+/* Select only one linked strip on each side. */
+static bool select_more_less_seq__internal(Scene *scene, bool select_more)
+{
+  Editing *ed = SEQ_editing_get(scene, false);
+
+  if (ed == NULL) {
+    return false;
+  }
+
+  GSet *neighbors = BLI_gset_new(BLI_ghashutil_ptrhash, BLI_ghashutil_ptrcmp, "Linked strips");
+  const int neighbor_selection_filter = select_more ? 0 : SELECT;
+  const int selection_filter = select_more ? SELECT : 0;
+
+  LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
+    if ((seq->flag & SELECT) != selection_filter) {
+      continue;
+    }
+    Sequence *neighbor = find_neighboring_sequence(
+        scene, seq, SEQ_SIDE_LEFT, neighbor_selection_filter);
+    if (neighbor) {
+      BLI_gset_add(neighbors, neighbor);
+    }
+    neighbor = find_neighboring_sequence(scene, seq, SEQ_SIDE_RIGHT, neighbor_selection_filter);
+    if (neighbor) {
+      BLI_gset_add(neighbors, neighbor);
     }
   }
 
+  bool changed = false;
+  GSetIterator gsi;
+  BLI_gsetIterator_init(&gsi, neighbors);
+  while (!BLI_gsetIterator_done(&gsi)) {
+    Sequence *neighbor = BLI_gsetIterator_getKey(&gsi);
+    if (select_more) {
+      neighbor->flag |= SELECT;
+      recurs_sel_seq(neighbor);
+    }
+    else {
+      neighbor->flag &= ~SELECT;
+    }
+    changed = true;
+    BLI_gsetIterator_step(&gsi);
+  }
+
+  BLI_gset_free(neighbors, NULL);
   return changed;
 }
 
@@ -841,7 +856,7 @@ static int sequencer_select_more_exec(bContext *C, wmOperator *UNUSED(op))
 {
   Scene *scene = CTX_data_scene(C);
 
-  if (!select_more_less_seq__internal(scene, true, false)) {
+  if (!select_more_less_seq__internal(scene, true)) {
     return OPERATOR_CANCELLED;
   }
 
@@ -877,7 +892,7 @@ static int sequencer_select_less_exec(bContext *C, wmOperator *UNUSED(op))
 {
   Scene *scene = CTX_data_scene(C);
 
-  if (!select_more_less_seq__internal(scene, false, false)) {
+  if (!select_more_less_seq__internal(scene, false)) {
     return OPERATOR_CANCELLED;
   }
 
@@ -934,7 +949,7 @@ static int sequencer_select_linked_pick_invoke(bContext *C, wmOperator *op, cons
 
   selected = 1;
   while (selected) {
-    selected = select_more_less_seq__internal(scene, 1, 1);
+    selected = select_linked_internal(scene);
   }
 
   ED_outliner_select_sync_from_sequence_tag(C);
@@ -975,7 +990,7 @@ static int sequencer_select_linked_exec(bContext *C, wmOperator *UNUSED(op))
 
   selected = true;
   while (selected) {
-    selected = select_more_less_seq__internal(scene, true, true);
+    selected = select_linked_internal(scene);
   }
 
   ED_outliner_select_sync_from_sequence_tag(C);