UV: Pack to closest/active UDIM

Implements T78397
Extends the functionality of pack islands operator to allow packing UVs
to either the closest or active UDIM tile.
This provides 2 new options for packing UVs :

* Closest UDIM: Selected UVs will be packed to the UDIM tile they were
  placed on. If not present on a valid UDIM tile, the UVs will be packed
  to the closest UDIM in UV space
* Active UDIM: Selected UVs will be packed to the active UDIM image tile
  In case, no image is present in the UV editor, then UVs will be packed
  to the tile on the UDIM grid where the 2D cursor is located.

Reviewed By: campbellbarton

Maniphest Tasks: T78397

Ref D12680

1 files changed, 68 insertions, 4 deletions

diff --git a/source/blender/editors/uvedit/uvedit_unwrap_ops.c b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
index 3d5dabda23d..4e183732db9 100644
--- a/source/blender/editors/uvedit/uvedit_unwrap_ops.c
+++ b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
@@ -37,6 +37,7 @@
 #include "BLI_alloca.h"
 #include "BLI_array.h"
 #include "BLI_linklist.h"
+#include "BLI_listbase.h"
 #include "BLI_math.h"
 #include "BLI_memarena.h"
 #include "BLI_string.h"
@@ -64,6 +65,7 @@
 #include "PIL_time.h"
 
 #include "UI_interface.h"
+#include "UI_view2d.h"
 
 #include "ED_image.h"
 #include "ED_mesh.h"
@@ -1005,10 +1007,17 @@ static void uvedit_pack_islands_multi(const Scene *scene,
   }
 }
 
+/* Packing targets. */
+enum {
+  PACK_UDIM_SRC_CLOSEST = 0,
+  PACK_UDIM_SRC_ACTIVE = 1,
+};
+
 static int pack_islands_exec(bContext *C, wmOperator *op)
 {
   ViewLayer *view_layer = CTX_data_view_layer(C);
   const Scene *scene = CTX_data_scene(C);
+  const SpaceImage *sima = CTX_wm_space_image(C);
 
   const UnwrapOptions options = {
       .topology_from_uvs = true,
@@ -1018,17 +1027,20 @@ static int pack_islands_exec(bContext *C, wmOperator *op)
       .correct_aspect = true,
   };
 
-  bool rotate = RNA_boolean_get(op->ptr, "rotate");
-
   uint objects_len = 0;
   Object **objects = BKE_view_layer_array_from_objects_in_edit_mode_unique_data_with_uvs(
       view_layer, CTX_wm_view3d(C), &objects_len);
 
+  /* Early exit in case no UVs are selected. */
   if (!uvedit_have_selection_multi(scene, objects, objects_len, &options)) {
     MEM_freeN(objects);
     return OPERATOR_CANCELLED;
   }
 
+  /* RNA props */
+  const bool rotate = RNA_boolean_get(op->ptr, "rotate");
+  const int udim_source = RNA_enum_get(op->ptr, "udim_source");
+  bool use_target_udim = false;
   if (RNA_struct_property_is_set(op->ptr, "margin")) {
     scene->toolsettings->uvcalc_margin = RNA_float_get(op->ptr, "margin");
   }
@@ -1036,9 +1048,46 @@ static int pack_islands_exec(bContext *C, wmOperator *op)
     RNA_float_set(op->ptr, "margin", scene->toolsettings->uvcalc_margin);
   }
 
+  int target_udim = 1001;
+  if (udim_source == PACK_UDIM_SRC_CLOSEST) {
+    /* pass */
+  }
+  else if (udim_source == PACK_UDIM_SRC_ACTIVE) {
+    int active_udim = 1001;
+    /* NOTE: Presently, when UDIM grid and tiled image are present together, only active tile for
+     * the tiled imgae is considered. */
+    if (sima && sima->image) {
+      Image *image = sima->image;
+      ImageTile *active_tile = BLI_findlink(&image->tiles, image->active_tile_index);
+      if (active_tile) {
+        active_udim = active_tile->tile_number;
+      }
+    }
+    else if (sima && !sima->image) {
+      /* Use 2D cursor to find the active tile index for the UDIM grid. */
+      float cursor_loc[2] = {sima->cursor[0], sima->cursor[1]};
+      if (uv_coords_isect_udim(sima->image, sima->tile_grid_shape, cursor_loc)) {
+        int tile_number = 1001;
+        tile_number += floorf(cursor_loc[1]) * 10;
+        tile_number += floorf(cursor_loc[0]);
+        active_udim = tile_number;
+      }
+      /* TODO: Support storing an active UDIM when there are no tiles present. */
+    }
+
+    target_udim = active_udim;
+    use_target_udim = true;
+  }
+  else {
+    BLI_assert_unreachable();
+  }
+
   ED_uvedit_pack_islands_multi(scene,
+                               sima,
                                objects,
                                objects_len,
+                               use_target_udim,
+                               target_udim,
                                &(struct UVPackIsland_Params){
                                    .rotate = rotate,
                                    .rotate_align_axis = -1,
@@ -1048,16 +1097,25 @@ static int pack_islands_exec(bContext *C, wmOperator *op)
                                });
 
   MEM_freeN(objects);
-
   return OPERATOR_FINISHED;
 }
 
 void UV_OT_pack_islands(wmOperatorType *ot)
 {
+  static const EnumPropertyItem pack_target[] = {
+      {PACK_UDIM_SRC_CLOSEST, "CLOSEST_UDIM", 0, "Closest UDIM", "Pack islands to closest UDIM"},
+      {PACK_UDIM_SRC_ACTIVE,
+       "ACTIVE_UDIM",
+       0,
+       "Active UDIM",
+       "Pack islands to active UDIM image tile or UDIM grid tile where 2D cursor is located"},
+      {0, NULL, 0, NULL, NULL},
+  };
   /* identifiers */
   ot->name = "Pack Islands";
   ot->idname = "UV_OT_pack_islands";
-  ot->description = "Transform all islands so that they fill up the UV space as much as possible";
+  ot->description =
+      "Transform all islands so that they fill up the UV/UDIM space as much as possible";
 
   ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
@@ -1066,6 +1124,7 @@ void UV_OT_pack_islands(wmOperatorType *ot)
   ot->poll = ED_operator_uvedit;
 
   /* properties */
+  RNA_def_enum(ot->srna, "udim_source", pack_target, PACK_UDIM_SRC_CLOSEST, "Pack to", "");
   RNA_def_boolean(ot->srna, "rotate", true, "Rotate", "Rotate islands for best fit");
   RNA_def_float_factor(
       ot->srna, "margin", 0.001f, 0.0f, 1.0f, "Margin", "Space between islands", 0.0f, 1.0f);
@@ -2055,6 +2114,7 @@ static int smart_project_exec(bContext *C, wmOperator *op)
 {
   Scene *scene = CTX_data_scene(C);
   ViewLayer *view_layer = CTX_data_view_layer(C);
+  const SpaceImage *sima = CTX_wm_space_image(C);
 
   /* May be NULL. */
   View3D *v3d = CTX_wm_view3d(C);
@@ -2065,6 +2125,7 @@ static int smart_project_exec(bContext *C, wmOperator *op)
 
   const float project_angle_limit_cos = cosf(project_angle_limit);
   const float project_angle_limit_half_cos = cosf(project_angle_limit / 2);
+  const int target_udim = 1001; /* 0-1 UV space. */
 
   /* Memory arena for list links (cleared for each object). */
   MemArena *arena = BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, __func__);
@@ -2204,8 +2265,11 @@ static int smart_project_exec(bContext *C, wmOperator *op)
     /* Depsgraph refresh functions are called here. */
     const bool correct_aspect = RNA_boolean_get(op->ptr, "correct_aspect");
     ED_uvedit_pack_islands_multi(scene,
+                                 sima,
                                  objects_changed,
                                  object_changed_len,
+                                 true,
+                                 target_udim,
                                  &(struct UVPackIsland_Params){
                                      .rotate = true,
                                      /* We could make this optional. */