source/blender/editors/uvedit/uvedit_unwrap_ops.cc

@@ -1382,9 +1382,10 @@ static void uvedit_pack_islands_multi(const Scene *scene,
     FaceIsland *face_island = island_vector[i];
     blender::geometry::PackIsland *pack_island = new blender::geometry::PackIsland();
     pack_island->bounds_rect = face_island->bounds_rect;
+    pack_island->caller_index = i;
     pack_island_vector.append(pack_island);
   }
-  BoxPack *box_array = pack_islands(pack_island_vector, *params, scale);
+  pack_islands(pack_island_vector, *params, scale);
 
   float base_offset[2] = {0.0f, 0.0f};
   copy_v2_v2(base_offset, params->udim_base_offset);
@@ -1423,8 +1424,9 @@ static void uvedit_pack_islands_multi(const Scene *scene,
   float matrix[2][2];
   float matrix_inverse[2][2];
   float pre_translate[2];
-  for (int i = 0; i < island_vector.size(); i++) {
-    FaceIsland *island = island_vector[box_array[i].index];
+  for (int64_t i : pack_island_vector.index_range()) {
+    blender::geometry::PackIsland *pack_island = pack_island_vector[i];
+    FaceIsland *island = island_vector[pack_island->caller_index];
     matrix[0][0] = scale[0];
     matrix[0][1] = 0.0f;
     matrix[1][0] = 0.0f;
@@ -1434,11 +1436,16 @@ static void uvedit_pack_islands_multi(const Scene *scene,
     /* Add base_offset, post transform. */
     mul_v2_m2v2(pre_translate, matrix_inverse, base_offset);
 
-    /* Translate to box_array from bounds_rect. */
-    blender::geometry::PackIsland *pack_island = pack_island_vector[box_array[i].index];
-    pre_translate[0] += box_array[i].x - pack_island->bounds_rect.xmin;
-    pre_translate[1] += box_array[i].y - pack_island->bounds_rect.ymin;
+    /* Add pre-translation from #pack_islands. */
+    pre_translate[0] += pack_island->pre_translate.x;
+    pre_translate[1] += pack_island->pre_translate.y;
+
+    /* Perform the transformation. */
     island_uv_transform(island, matrix, pre_translate);
+
+    /* Cleanup memory. */
+    pack_island_vector[i] = nullptr;
+    delete pack_island;
   }
 
   for (uint ob_index = 0; ob_index < objects_len; ob_index++) {
@@ -1451,14 +1458,6 @@ static void uvedit_pack_islands_multi(const Scene *scene,
     MEM_freeN(island->faces);
     MEM_freeN(island);
   }
-
-  for (int i = 0; i < pack_island_vector.size(); i++) {
-    blender::geometry::PackIsland *pack_island = pack_island_vector[i];
-    pack_island_vector[i] = nullptr;
-    delete pack_island;
-  }
-
-  MEM_freeN(box_array);
 }
 
 /* -------------------------------------------------------------------- */

source/blender/geometry/GEO_uv_pack.hh

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 
-#include "BLI_boxpack_2d.h"
+#include "BLI_math_matrix.hh"
 #include "BLI_span.hh"
 
 #include "DNA_vec_types.h"
@@ -46,10 +46,12 @@ namespace blender::geometry {
 class PackIsland {
  public:
   rctf bounds_rect;
+  float2 pre_translate; /* Output. */
+  int caller_index;     /* Unchanged by #pack_islands, used by caller. */
 };
 
-BoxPack *pack_islands(const Span<PackIsland *> &island_vector,
-                      const UVPackIsland_Params &params,
-                      float r_scale[2]);
+void pack_islands(const Span<PackIsland *> &islands,
+                  const UVPackIsland_Params &params,
+                  float r_scale[2]);
 
 }  // namespace blender::geometry

source/blender/geometry/intern/uv_pack.cc

@@ -11,7 +11,6 @@
 #include "BLI_convexhull_2d.h"
 #include "BLI_listbase.h"
 #include "BLI_math.h"
-#include "BLI_math_matrix.hh"
 #include "BLI_rect.h"
 #include "BLI_vector.hh"
 
@@ -302,9 +301,9 @@ static float calc_margin_from_aabb_length_sum(const Span<PackIsland *> &island_v
   return params.margin * aabb_length_sum * 0.1f;
 }
 
-BoxPack *pack_islands(const Span<PackIsland *> &island_vector,
-                      const UVPackIsland_Params &params,
-                      float r_scale[2])
+static BoxPack *pack_islands_box_array(const Span<PackIsland *> &island_vector,
+                                       const UVPackIsland_Params &params,
+                                       float r_scale[2])
 {
   BoxPack *box_array = static_cast<BoxPack *>(
       MEM_mallocN(sizeof(*box_array) * island_vector.size(), __func__));
@@ -351,4 +350,20 @@ BoxPack *pack_islands(const Span<PackIsland *> &island_vector,
   return box_array;
 }
 
+void pack_islands(const Span<PackIsland *> &islands,
+                  const UVPackIsland_Params &params,
+                  float r_scale[2])
+{
+  BoxPack *box_array = pack_islands_box_array(islands, params, r_scale);
+
+  for (int64_t i : islands.index_range()) {
+    BoxPack *box = box_array + i;
+    PackIsland *island = islands[box->index];
+    island->pre_translate.x = box->x - island->bounds_rect.xmin;
+    island->pre_translate.y = box->y - island->bounds_rect.ymin;
+  }
+
+  MEM_freeN(box_array);
+}
+
 }  // namespace blender::geometry

source/blender/geometry/intern/uv_parametrizer.cc

@@ -4167,6 +4167,7 @@ void uv_parametrizer_pack(ParamHandle *handle, float margin, bool do_rotate, boo
     }
 
     geometry::PackIsland *pack_island = new geometry::PackIsland();
+    pack_island->caller_index = i;
     pack_island_vector.append(pack_island);
 
     float minv[2];
@@ -4192,42 +4193,29 @@ void uv_parametrizer_pack(ParamHandle *handle, float margin, bool do_rotate, boo
   params.udim_base_offset[1] = 0.0f;
 
   float scale[2] = {1.0f, 1.0f};
-  BoxPack *box_array = pack_islands(pack_island_vector, params, scale);
+  pack_islands(pack_island_vector, params, scale);
 
   for (int64_t i : pack_island_vector.index_range()) {
-    BoxPack *box = box_array + i;
-    PackIsland *pack_island = pack_island_vector[box->index];
-    pack_island->bounds_rect.xmin = box->x - pack_island->bounds_rect.xmin;
-    pack_island->bounds_rect.ymin = box->y - pack_island->bounds_rect.ymin;
-  }
-
-  unpacked = 0;
-  for (int i = 0; i < handle->ncharts; i++) {
-    PChart *chart = handle->charts[i];
-
-    if (ignore_pinned && chart->has_pins) {
-      unpacked++;
-      continue;
-    }
-    PackIsland *pack_island = pack_island_vector[i - unpacked];
+    PackIsland *pack_island = pack_island_vector[i];
+    PChart *chart = handle->charts[pack_island->caller_index];
 
     /* TODO: Replace with #mul_v2_m2_add_v2v2 here soon. */
     float m[2];
     float b[2];
     m[0] = scale[0];
     m[1] = scale[1];
-    b[0] = pack_island->bounds_rect.xmin;
-    b[1] = pack_island->bounds_rect.ymin;
+    b[0] = pack_island->pre_translate.x;
+    b[1] = pack_island->pre_translate.y;
     for (PVert *v = chart->verts; v; v = v->nextlink) {
       /* Unusual accumulate-and-multiply here (will) reduce round-off error. */
       v->uv[0] = m[0] * (v->uv[0] + b[0]);
       v->uv[1] = m[1] * (v->uv[1] + b[1]);
     }
 
-    pack_island_vector[i - unpacked] = nullptr;
+    pack_island_vector[i] = nullptr;
     delete pack_island;
   }
-  MEM_freeN(box_array);
+
   if (handle->aspx != handle->aspy) {
     uv_parametrizer_scale(handle, handle->aspx, handle->aspy);
   }