[Bf-blender-cvs] [05a2382c084] blender-v2.91-release: Fix T82540: Smart UV project ignores seams

[Campbell Barton]

Commit: 05a2382c08402b250d6b5c4105b449f4474f6cf2
Author: Campbell Barton
Date:   Tue Nov 10 19:05:07 2020 +1100
Branches: blender-v2.91-release
https://developer.blender.org/rB05a2382c08402b250d6b5c4105b449f4474f6cf2

Fix T82540: Smart UV project ignores seams

Functionality was lost in the Python to C conversion from
850234c1b10a828678f1b91001f2731db807f7e2

===================================================================

M	source/blender/editors/uvedit/uvedit_unwrap_ops.c

===================================================================

diff --git a/source/blender/editors/uvedit/uvedit_unwrap_ops.c b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
index cfcef0ebcb9..a50386a64e2 100644
--- a/source/blender/editors/uvedit/uvedit_unwrap_ops.c
+++ b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
@@ -149,6 +149,8 @@ static bool ED_uvedit_ensure_uvs(Object *obedit)
 typedef struct UnwrapOptions {
   /** Connectivity based on UV coordinates instead of seams. */
   bool topology_from_uvs;
+  /** Also use seams as well as UV coordinates (only valid when `topology_from_uvs` is enabled). */
+  bool topology_from_uvs_use_seams;
   /** Only affect selected faces. */
   bool only_selected_faces;
   /**
@@ -331,7 +333,7 @@ static ParamHandle *construct_param_handle(const Scene *scene,
     construct_param_handle_face_add(handle, scene, efa, i, cd_loop_uv_offset);
   }
 
-  if (!options->topology_from_uvs) {
+  if (!options->topology_from_uvs || options->topology_from_uvs_use_seams) {
     BM_ITER_MESH (eed, &iter, bm, BM_EDGES_OF_MESH) {
       if (BM_elem_flag_test(eed, BM_ELEM_SEAM)) {
         ParamKey vkeys[2];
@@ -416,7 +418,7 @@ static ParamHandle *construct_param_handle_multi(const Scene *scene,
       construct_param_handle_face_add(handle, scene, efa, i + offset, cd_loop_uv_offset);
     }
 
-    if (!options->topology_from_uvs) {
+    if (!options->topology_from_uvs || options->topology_from_uvs_use_seams) {
       BM_ITER_MESH (eed, &iter, bm, BM_EDGES_OF_MESH) {
         if (BM_elem_flag_test(eed, BM_ELEM_SEAM)) {
           ParamKey vkeys[2];
@@ -2149,6 +2151,10 @@ static int smart_project_exec(bContext *C, wmOperator *op)
     scene->toolsettings->uvcalc_margin = island_margin;
     const UnwrapOptions options = {
         .topology_from_uvs = true,
+        /* Even though the islands are defined by UV's,
+         * split them by seams so users have control over the islands. */
+        .topology_from_uvs_use_seams = true,
+
         .only_selected_faces = true,
         .only_selected_uvs = false,
         .fill_holes = true,