GPencil: New Append operators

Now it's possible to append materials of one grease pencil object into another one. The operator allows active material or all materials.

Also, the Layer Copy To Object has been renamed to Layer Append to Object to keep consistency and now allows to append all layers at once.

6 files changed, 221 insertions, 51 deletions

diff --git a/release/scripts/startup/bl_ui/properties_data_gpencil.py b/release/scripts/startup/bl_ui/properties_data_gpencil.py
index 69720a6c54b..d88c9a3502d 100644
--- a/release/scripts/startup/bl_ui/properties_data_gpencil.py
+++ b/release/scripts/startup/bl_ui/properties_data_gpencil.py
@@ -113,7 +113,8 @@ class GPENCIL_MT_layer_context_menu(Menu):
         layout.operator("gpencil.layer_merge", icon='SORT_ASC', text="Merge Down")
 
         layout.separator()
-        layout.menu("VIEW3D_MT_gpencil_copy_layer")
+        layout.menu("VIEW3D_MT_gpencil_append_active_layer")
+        layout.menu("VIEW3D_MT_gpencil_append_all_layers")
 
 
 class DATA_PT_gpencil_layers(DataButtonsPanel, Panel):
diff --git a/release/scripts/startup/bl_ui/properties_material_gpencil.py b/release/scripts/startup/bl_ui/properties_material_gpencil.py
index 6a5c000116f..ed5863b463a 100644
--- a/release/scripts/startup/bl_ui/properties_material_gpencil.py
+++ b/release/scripts/startup/bl_ui/properties_material_gpencil.py
@@ -53,6 +53,10 @@ class GPENCIL_MT_material_context_menu(Menu):
         layout.operator("gpencil.material_to_vertex_color", text="Convert Materials to Vertex Color")
         layout.operator("gpencil.extract_palette_vertex", text="Extract Palette from Vertex Color")
 
+        layout.separator()
+        layout.menu("VIEW3D_MT_gpencil_append_active_material")
+        layout.menu("VIEW3D_MT_gpencil_append_all_materials")
+
 
 class GPENCIL_UL_matslots(UIList):
     def draw_item(self, _context, layout, _data, item, icon, _active_data, _active_propname, _index):
diff --git a/release/scripts/startup/bl_ui/space_view3d.py b/release/scripts/startup/bl_ui/space_view3d.py
index bdc924e3197..4b06a2df3a0 100644
--- a/release/scripts/startup/bl_ui/space_view3d.py
+++ b/release/scripts/startup/bl_ui/space_view3d.py
@@ -4956,26 +4956,73 @@ class VIEW3D_MT_assign_material(Menu):
                                 icon='LAYER_ACTIVE' if mat == mat_active else 'BLANK1').material = mat.name
 
 
-class VIEW3D_MT_gpencil_copy_layer(Menu):
-    bl_label = "Copy Layer to Object"
+def gpencil_layer_append_menu_items(context, layout, only_active):
+    done = False
+    view_layer = context.view_layer
+    obact = context.active_object
+    gpl = context.active_gpencil_layer
+
+    done = False
+    if gpl is not None:
+        for ob in view_layer.objects:
+            if ob.type == 'GPENCIL' and ob != obact:
+                op = layout.operator("gpencil.layer_duplicate_object", text=ob.name)
+                op.object = ob.name
+                op.only_active = only_active
+                done = True
+
+        if done is False:
+            layout.label(text="No destination object", icon='ERROR')
+    else:
+        layout.label(text="No layer to copy", icon='ERROR')
+
+
+class VIEW3D_MT_gpencil_append_active_layer(Menu):
+    bl_label = "Append Active Layer to Object"
 
     def draw(self, context):
         layout = self.layout
-        view_layer = context.view_layer
-        obact = context.active_object
-        gpl = context.active_gpencil_layer
-
-        done = False
-        if gpl is not None:
-            for ob in view_layer.objects:
-                if ob.type == 'GPENCIL' and ob != obact:
-                    layout.operator("gpencil.layer_duplicate_object", text=ob.name).object = ob.name
-                    done = True
-
-            if done is False:
-                layout.label(text="No destination object", icon='ERROR')
-        else:
-            layout.label(text="No layer to copy", icon='ERROR')
+        gpencil_layer_append_menu_items(context, layout, True)
+
+
+class VIEW3D_MT_gpencil_append_all_layers(Menu):
+    bl_label = "Append All Layers to Object"
+
+    def draw(self, context):
+        layout = self.layout
+        gpencil_layer_append_menu_items(context, layout, False)
+
+
+def gpencil_material_menu_items(context, layout, only_selected):
+    done = False
+    view_layer = context.view_layer
+    obact = context.active_object
+
+    for ob in view_layer.objects:
+        if ob.type == 'GPENCIL' and ob != obact:
+            op = layout.operator("gpencil.materials_append_to_object", text=ob.name)
+            op.object = ob.name
+            op.only_selected = only_selected
+            done = True
+
+    if done is False:
+        layout.label(text="No destination object", icon='ERROR')
+
+
+class VIEW3D_MT_gpencil_append_active_material(Menu):
+    bl_label = "Append Active Material to Object"
+
+    def draw(self, context):
+        layout = self.layout
+        gpencil_material_menu_items(context, layout, True)
+
+
+class VIEW3D_MT_gpencil_append_all_materials(Menu):
+    bl_label = "Append All Materials to Object"
+
+    def draw(self, context):
+        layout = self.layout
+        gpencil_material_menu_items(context, layout, False)
 
 
 class VIEW3D_MT_edit_gpencil(Menu):
@@ -7642,7 +7689,10 @@ classes = (
     VIEW3D_MT_weight_gpencil,
     VIEW3D_MT_gpencil_animation,
     VIEW3D_MT_gpencil_simplify,
-    VIEW3D_MT_gpencil_copy_layer,
+    VIEW3D_MT_gpencil_append_active_layer,
+    VIEW3D_MT_gpencil_append_all_layers,
+    VIEW3D_MT_gpencil_append_active_material,
+    VIEW3D_MT_gpencil_append_all_materials,
     VIEW3D_MT_gpencil_autoweights,
     VIEW3D_MT_gpencil_edit_context_menu,
     VIEW3D_MT_edit_curve,
diff --git a/source/blender/editors/gpencil/gpencil_data.c b/source/blender/editors/gpencil/gpencil_data.c
index c93fcb9eb8c..c5f094e030a 100644
--- a/source/blender/editors/gpencil/gpencil_data.c
+++ b/source/blender/editors/gpencil/gpencil_data.c
@@ -557,6 +557,7 @@ static int gpencil_layer_duplicate_object_exec(bContext *C, wmOperator *op)
   if (name[0] == '\0') {
     return OPERATOR_CANCELLED;
   }
+  const bool only_active = RNA_boolean_get(op->ptr, "only_active");
 
   Object *ob_dst = (Object *)BKE_scene_object_find_by_name(scene, name);
 
@@ -564,10 +565,10 @@ static int gpencil_layer_duplicate_object_exec(bContext *C, wmOperator *op)
 
   Object *ob_src = CTX_data_active_object(C);
   bGPdata *gpd_src = (bGPdata *)ob_src->data;
-  bGPDlayer *gpl_src = BKE_gpencil_layer_active_get(gpd_src);
+  bGPDlayer *gpl_active = BKE_gpencil_layer_active_get(gpd_src);
 
   /* Sanity checks. */
-  if (ELEM(NULL, gpd_src, gpl_src, ob_dst)) {
+  if (ELEM(NULL, gpd_src, ob_dst)) {
     return OPERATOR_CANCELLED;
   }
   /* Cannot copy itself and check destination type. */
@@ -576,47 +577,55 @@ static int gpencil_layer_duplicate_object_exec(bContext *C, wmOperator *op)
   }
 
   bGPdata *gpd_dst = (bGPdata *)ob_dst->data;
+  /* Disable destination active layer to keep order. */
+  LISTBASE_FOREACH (bGPDlayer *, gpl, &gpd_dst->layers) {
+    gpl->flag &= ~GP_LAYER_ACTIVE;
+  }
 
-  /* Create new layer. */
-  bGPDlayer *gpl_dst = BKE_gpencil_layer_addnew(gpd_dst, gpl_src->info, true);
-  /* Need to copy some variables (not all). */
-  gpl_dst->onion_flag = gpl_src->onion_flag;
-  gpl_dst->thickness = gpl_src->thickness;
-  gpl_dst->line_change = gpl_src->line_change;
-  copy_v4_v4(gpl_dst->tintcolor, gpl_src->tintcolor);
-  gpl_dst->opacity = gpl_src->opacity;
-
-  /* Create all frames. */
-  LISTBASE_FOREACH (bGPDframe *, gpf_src, &gpl_src->frames) {
-
-    if ((mode == GP_LAYER_COPY_OBJECT_ACT_FRAME) && (gpf_src != gpl_src->actframe)) {
+  LISTBASE_FOREACH (bGPDlayer *, gpl_src, &gpd_src->layers) {
+    if ((only_active) && (gpl_src != gpl_active)) {
       continue;
     }
+    /* Create new layer. */
+    bGPDlayer *gpl_dst = BKE_gpencil_layer_addnew(gpd_dst, gpl_src->info, true);
+    /* Need to copy some variables (not all). */
+    gpl_dst->onion_flag = gpl_src->onion_flag;
+    gpl_dst->thickness = gpl_src->thickness;
+    gpl_dst->line_change = gpl_src->line_change;
+    copy_v4_v4(gpl_dst->tintcolor, gpl_src->tintcolor);
+    gpl_dst->opacity = gpl_src->opacity;
 
-    /* Create new frame. */
-    bGPDframe *gpf_dst = BKE_gpencil_frame_addnew(gpl_dst, gpf_src->framenum);
+    /* Create all frames. */
+    LISTBASE_FOREACH (bGPDframe *, gpf_src, &gpl_src->frames) {
 
-    /* Copy strokes. */
-    LISTBASE_FOREACH (bGPDstroke *, gps_src, &gpf_src->strokes) {
+      if ((mode == GP_LAYER_COPY_OBJECT_ACT_FRAME) && (gpf_src != gpl_src->actframe)) {
+        continue;
+      }
 
-      /* Make copy of source stroke. */
-      bGPDstroke *gps_dst = BKE_gpencil_stroke_duplicate(gps_src, true, true);
+      /* Create new frame. */
+      bGPDframe *gpf_dst = BKE_gpencil_frame_addnew(gpl_dst, gpf_src->framenum);
 
-      /* Check if material is in destination object,
-       * otherwise add the slot with the material. */
-      Material *ma_src = BKE_object_material_get(ob_src, gps_src->mat_nr + 1);
-      if (ma_src != NULL) {
-        int idx = BKE_gpencil_object_material_ensure(bmain, ob_dst, ma_src);
+      /* Copy strokes. */
+      LISTBASE_FOREACH (bGPDstroke *, gps_src, &gpf_src->strokes) {
 
-        /* Reassign the stroke material to the right slot in destination object. */
-        gps_dst->mat_nr = idx;
-      }
+        /* Make copy of source stroke. */
+        bGPDstroke *gps_dst = BKE_gpencil_stroke_duplicate(gps_src, true, true);
+
+        /* Check if material is in destination object,
+         * otherwise add the slot with the material. */
+        Material *ma_src = BKE_object_material_get(ob_src, gps_src->mat_nr + 1);
+        if (ma_src != NULL) {
+          int idx = BKE_gpencil_object_material_ensure(bmain, ob_dst, ma_src);
 
-      /* Add new stroke to frame. */
-      BLI_addtail(&gpf_dst->strokes, gps_dst);
+          /* Reassign the stroke material to the right slot in destination object. */
+          gps_dst->mat_nr = idx;
+        }
+
+        /* Add new stroke to frame. */
+        BLI_addtail(&gpf_dst->strokes, gps_dst);
+      }
     }
   }
-
   /* notifiers */
   DEG_id_tag_update(&gpd_dst->id,
                     ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY | ID_RECALC_COPY_ON_WRITE);
@@ -628,6 +637,8 @@ static int gpencil_layer_duplicate_object_exec(bContext *C, wmOperator *op)
 
 void GPENCIL_OT_layer_duplicate_object(wmOperatorType *ot)
 {
+  PropertyRNA *prop;
+
   static const EnumPropertyItem copy_mode[] = {
       {GP_LAYER_COPY_OBJECT_ALL_FRAME, "ALL", 0, "All Frames", ""},
       {GP_LAYER_COPY_OBJECT_ACT_FRAME, "ACTIVE", 0, "Active Frame", ""},
@@ -651,6 +662,13 @@ void GPENCIL_OT_layer_duplicate_object(wmOperatorType *ot)
   RNA_def_property_flag(ot->prop, PROP_HIDDEN | PROP_SKIP_SAVE);
 
   RNA_def_enum(ot->srna, "mode", copy_mode, GP_LAYER_COPY_OBJECT_ALL_FRAME, "Mode", "");
+
+  prop = RNA_def_boolean(ot->srna,
+                         "only_active",
+                         true,
+                         "Only Active",
+                         "Append only active Layer, uncheck to append all layers");
+  RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
 }
 
 /* ********************* Duplicate Frame ************************** */
@@ -3589,6 +3607,101 @@ void GPENCIL_OT_set_active_material(wmOperatorType *ot)
   ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
+/* ********************* Append Materials in a new object ************************** */
+static bool gpencil_materials_append_to_object_poll(bContext *C)
+{
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  Object *ob = CTX_data_active_object(C);
+  if ((ob == NULL) || (ob->type != OB_GPENCIL)) {
+    return false;
+  }
+  short *totcolp = BKE_object_material_len_p(ob);
+  if (*totcolp == 0) {
+    return false;
+  }
+
+  /* check there are more grease pencil objects */
+  LISTBASE_FOREACH (Base *, base, &view_layer->object_bases) {
+    if ((base->object != ob) && (base->object->type == OB_GPENCIL)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+static int gpencil_materials_append_to_object_exec(bContext *C, wmOperator *op)
+{
+  Main *bmain = CTX_data_main(C);
+  Scene *scene = CTX_data_scene(C);
+  char name[MAX_ID_NAME - 2];
+  RNA_string_get(op->ptr, "object", name);
+
+  if (name[0] == '\0') {
+    return OPERATOR_CANCELLED;
+  }
+  const bool only_selected = RNA_boolean_get(op->ptr, "only_selected");
+
+  Object *ob_dst = (Object *)BKE_scene_object_find_by_name(scene, name);
+  Object *ob_src = CTX_data_active_object(C);
+  Material *ma_active = BKE_gpencil_material(ob_src, ob_src->actcol);
+
+  /* Sanity checks. */
+  if (ELEM(NULL, ob_src, ob_dst)) {
+    return OPERATOR_CANCELLED;
+  }
+  /* Cannot copy itself and check destination type. */
+  if ((ob_src == ob_dst) || (ob_dst->type != OB_GPENCIL)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  /* Duplicate materials. */
+  for (short i = 0; i < ob_src->totcol; i++) {
+    Material *ma_src = BKE_object_material_get(ob_src, i + 1);
+    if (only_selected && ma_src != ma_active) {
+      continue;
+    }
+
+    if (ma_src != NULL) {
+      BKE_gpencil_object_material_ensure(bmain, ob_dst, ma_src);
+    }
+  }
+
+  /* notifiers */
+  DEG_id_tag_update(&ob_dst->id, ID_RECALC_COPY_ON_WRITE);
+  WM_event_add_notifier(C, NC_GPENCIL | ND_DATA | NA_EDITED, NULL);
+
+  return OPERATOR_FINISHED;
+}
+
+void GPENCIL_OT_materials_append_to_object(wmOperatorType *ot)
+{
+  PropertyRNA *prop;
+
+  /* identifiers */
+  ot->name = "Append Materials to New Object";
+  ot->idname = "GPENCIL_OT_materials_append_to_object";
+  ot->description = "Append Materials of the active Grease Pencil to other object";
+
+  /* callbacks */
+  ot->exec = gpencil_materials_append_to_object_exec;
+  ot->poll = gpencil_materials_append_to_object_poll;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  ot->prop = RNA_def_string(
+      ot->srna, "object", NULL, MAX_ID_NAME - 2, "Object", "Name of the destination object");
+  RNA_def_property_flag(ot->prop, PROP_HIDDEN | PROP_SKIP_SAVE);
+
+  prop = RNA_def_boolean(ot->srna,
+                         "only_selected",
+                         true,
+                         "Only Selected",
+                         "Append only selected material, uncheck to append all materials");
+  RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
+}
+
 /* Parent GPencil object to Lattice */
 bool ED_gpencil_add_lattice_modifier(const bContext *C,
                                      ReportList *reports,
diff --git a/source/blender/editors/gpencil/gpencil_intern.h b/source/blender/editors/gpencil/gpencil_intern.h
index 09200125cb7..cce56acd3e4 100644
--- a/source/blender/editors/gpencil/gpencil_intern.h
+++ b/source/blender/editors/gpencil/gpencil_intern.h
@@ -538,6 +538,7 @@ void GPENCIL_OT_material_lock_unused(struct wmOperatorType *ot);
 void GPENCIL_OT_material_select(struct wmOperatorType *ot);
 void GPENCIL_OT_material_set(struct wmOperatorType *ot);
 void GPENCIL_OT_set_active_material(struct wmOperatorType *ot);
+void GPENCIL_OT_materials_append_to_object(struct wmOperatorType *ot);
 
 /* convert old 2.7 files to 2.8 */
 void GPENCIL_OT_convert_old_files(struct wmOperatorType *ot);
diff --git a/source/blender/editors/gpencil/gpencil_ops.c b/source/blender/editors/gpencil/gpencil_ops.c
index 7d454eb3be1..6ac1161bff8 100644
--- a/source/blender/editors/gpencil/gpencil_ops.c
+++ b/source/blender/editors/gpencil/gpencil_ops.c
@@ -651,6 +651,7 @@ void ED_operatortypes_gpencil(void)
 
   WM_operatortype_append(GPENCIL_OT_material_to_vertex_color);
   WM_operatortype_append(GPENCIL_OT_extract_palette_vertex);
+  WM_operatortype_append(GPENCIL_OT_materials_append_to_object);
 
   WM_operatortype_append(GPENCIL_OT_transform_fill);
   WM_operatortype_append(GPENCIL_OT_reset_transform_fill);