From 0ce18561bc82f533d248f0f7268263abc0fc6fe1 Mon Sep 17 00:00:00 2001
From: Chris Blackbourn <chrisbblend@gmail.com>
Date: Fri, 25 Nov 2022 15:48:17 +1300
Subject: [PATCH] Fix (unreported) uv unwrap selected was splitting selection

Add support for `pin_unselected` in new UV Packing API.

Regression introduced by API change in rBe3075f3cf7ce.
---
 source/blender/editors/include/ED_uvedit.h      |  1 +
 source/blender/editors/uvedit/uvedit_islands.cc | 17 +++++++++++++----
 .../blender/editors/uvedit/uvedit_unwrap_ops.c  |  3 +++
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/source/blender/editors/include/ED_uvedit.h b/source/blender/editors/include/ED_uvedit.h
index 5fea8711a84..4a7081baa38 100644
--- a/source/blender/editors/include/ED_uvedit.h
+++ b/source/blender/editors/include/ED_uvedit.h
@@ -353,6 +353,7 @@ struct UVPackIsland_Params {
   uint use_seams : 1;
   uint correct_aspect : 1;
   bool ignore_pinned;                       /* Ignore islands which have any pinned UVs. */
+  bool pin_unselected;                      /* Treat unselected UVs as if they were pinned. */
   eUVPackIsland_MarginMethod margin_method; /* Which formula to use when scaling island margin. */
   float margin;                             /* Additional space to add around each island. */
 };
diff --git a/source/blender/editors/uvedit/uvedit_islands.cc b/source/blender/editors/uvedit/uvedit_islands.cc
index d8e10435146..61fd1c53b95 100644
--- a/source/blender/editors/uvedit/uvedit_islands.cc
+++ b/source/blender/editors/uvedit/uvedit_islands.cc
@@ -618,7 +618,7 @@ static BoxPack *pack_islands_params(const blender::Vector<FaceIsland *> &island_
   return box_array;
 }
 
-static bool island_has_pins(FaceIsland *island)
+static bool island_has_pins(const Scene *scene, FaceIsland *island, const bool pin_unselected)
 {
   BMLoop *l;
   BMIter iter;
@@ -629,6 +629,9 @@ static bool island_has_pins(FaceIsland *island)
       if (luv->flag & MLOOPUV_PINNED) {
         return true;
       }
+      if (pin_unselected && !uvedit_uv_select_test(scene, l, cd_loop_uv_offset)) {
+        return true;
+      }
     }
   }
   return false;
@@ -675,12 +678,18 @@ void ED_uvedit_pack_islands_multi(const Scene *scene,
       }
     }
 
+    bool only_selected_faces = params->only_selected_faces;
+    bool only_selected_uvs = params->only_selected_uvs;
+    if (params->ignore_pinned && params->pin_unselected) {
+      only_selected_faces = false;
+      only_selected_uvs = false;
+    }
     ListBase island_list = {nullptr};
     bm_mesh_calc_uv_islands(scene,
                             bm,
                             &island_list,
-                            params->only_selected_faces,
-                            params->only_selected_uvs,
+                            only_selected_faces,
+                            only_selected_uvs,
                             params->use_seams,
                             aspect_y,
                             cd_loop_uv_offset);
@@ -688,7 +697,7 @@ void ED_uvedit_pack_islands_multi(const Scene *scene,
     /* Remove from linked list and append to blender::Vector. */
     LISTBASE_FOREACH_MUTABLE (struct FaceIsland *, island, &island_list) {
       BLI_remlink(&island_list, island);
-      if (params->ignore_pinned && island_has_pins(island)) {
+      if (params->ignore_pinned && island_has_pins(scene, island, params->pin_unselected)) {
         MEM_freeN(island->faces);
         MEM_freeN(island);
         continue;
diff --git a/source/blender/editors/uvedit/uvedit_unwrap_ops.c b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
index ce9a083dfeb..b310132bdd2 100644
--- a/source/blender/editors/uvedit/uvedit_unwrap_ops.c
+++ b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
@@ -1100,6 +1100,7 @@ static int pack_islands_exec(bContext *C, wmOperator *op)
       .use_seams = !options.topology_from_uvs || options.topology_from_uvs_use_seams,
       .correct_aspect = options.correct_aspect,
       .ignore_pinned = false,
+      .pin_unselected = options.pin_unselected,
       .margin_method = RNA_enum_get(op->ptr, "margin_method"),
       .margin = RNA_float_get(op->ptr, "margin"),
   };
@@ -1878,6 +1879,7 @@ void ED_uvedit_live_unwrap(const Scene *scene, Object **objects, int objects_len
         .use_seams = !options.topology_from_uvs || options.topology_from_uvs_use_seams,
         .correct_aspect = options.correct_aspect,
         .ignore_pinned = true,
+        .pin_unselected = options.pin_unselected,
         .margin_method = ED_UVPACK_MARGIN_SCALED,
         .margin = scene->toolsettings->uvcalc_margin,
     };
@@ -2025,6 +2027,7 @@ static int unwrap_exec(bContext *C, wmOperator *op)
       .use_seams = !options.topology_from_uvs || options.topology_from_uvs_use_seams,
       .correct_aspect = options.correct_aspect,
       .ignore_pinned = true,
+      .pin_unselected = options.pin_unselected,
       .margin_method = RNA_enum_get(op->ptr, "margin_method"),
       .margin = RNA_float_get(op->ptr, "margin"),
   };