Fix T91463: Separate points makes gap on cyclic stroke

If an entire cyclic stroke was selected, calling "Separate by Points"
would leave a gap in the new object (making the new stroke non-cyclic).

The patch makes sure that if we separate by points and all points are
selected, we fall back to separate by stroke.

Reviewed By: antoniov

Maniphest Tasks: T91463

Differential Revision: https://developer.blender.org/D12527

1 files changed, 25 insertions, 0 deletions

diff --git a/source/blender/editors/gpencil/gpencil_edit.c b/source/blender/editors/gpencil/gpencil_edit.c
index e71a56894d0..afb786da8c6 100644
--- a/source/blender/editors/gpencil/gpencil_edit.c
+++ b/source/blender/editors/gpencil/gpencil_edit.c
@@ -4626,6 +4626,31 @@ static int gpencil_stroke_separate_exec(bContext *C, wmOperator *op)
                   BKE_report(op->reports, RPT_ERROR, "Not implemented!");
                 }
                 else {
+                  /* Check if all points are selected. */
+                  bool all_points_selected = true;
+                  for (i = 0, pt = gps->points; i < gps->totpoints; i++, pt++) {
+                    if ((pt->flag & GP_SPOINT_SELECT) == 0) {
+                      all_points_selected = false;
+                      break;
+                    }
+                  }
+
+                  /* Separate the entrie stroke. */
+                  if (all_points_selected) {
+                    /* deselect old stroke */
+                    gps->flag &= ~GP_STROKE_SELECT;
+                    BKE_gpencil_stroke_select_index_reset(gps);
+                    /* unlink from source frame */
+                    BLI_remlink(&gpf->strokes, gps);
+                    gps->prev = gps->next = NULL;
+                    /* relink to destination frame */
+                    BLI_addtail(&gpf_dst->strokes, gps);
+                    /* Reassign material. */
+                    gps->mat_nr = idx;
+
+                    continue;
+                  }
+
                   /* make copy of source stroke */
                   bGPDstroke *gps_dst = BKE_gpencil_stroke_duplicate(gps, true, true);