Collection Manager: Object selection. Task: T69577

Adds the ability to select all object in a QCD slot.
Alt+LMB deselects everything and selects all objects in the QCD slot.
Alt+Shift+LMB adds/removes objects in the QCD slot to/from the selection.

Added a selection operator for use in the Collection Manager popup.
(currently unused)

4 files changed, 112 insertions, 16 deletions

diff --git a/object_collection_manager/__init__.py b/object_collection_manager/__init__.py
index 09cb1c2c..49bd0de9 100644
--- a/object_collection_manager/__init__.py
+++ b/object_collection_manager/__init__.py
@@ -22,7 +22,7 @@ bl_info = {
     "name": "Collection Manager",
     "description": "Manage collections and their objects",
     "author": "Ryan Inch",
-    "version": (2, 12, 5),
+    "version": (2, 13, 0),
     "blender": (2, 80, 0),
     "location": "View3D - Object Mode (Shortcut - M)",
     "warning": '',  # used for warning icon and text in addons panel
@@ -111,6 +111,7 @@ classes = (
     operators.CMNewCollectionOperator,
     operators.CMRemoveCollectionOperator,
     operators.CMRemoveEmptyCollectionsOperator,
+    operators.CMSelectCollectionObjectsOperator,
     operators.CMSetCollectionOperator,
     operators.CMPhantomModeOperator,
     operators.CMApplyPhantomModeOperator,
diff --git a/object_collection_manager/operator_utils.py b/object_collection_manager/operator_utils.py
index d86a534f..ed7fce09 100644
--- a/object_collection_manager/operator_utils.py
+++ b/object_collection_manager/operator_utils.py
@@ -28,6 +28,7 @@ from .internals import (
     copy_buffer,
     swap_buffer,
     update_property_group,
+    get_move_selection,
 )
 
 rto_path = {
@@ -57,20 +58,21 @@ def set_rto(layer_collection, rto, value):
         setattr(collection, rto_path[rto].split(".")[1], value)
 
 
-def apply_to_children(laycol, apply_function):
-    laycol_iter_list = [laycol.children]
+def apply_to_children(parent, apply_function):
+    # works for both Collections & LayerCollections
+    child_lists = [parent.children]
 
-    while len(laycol_iter_list) > 0:
-        new_laycol_iter_list = []
+    while child_lists:
+        new_child_lists = []
 
-        for laycol_iter in laycol_iter_list:
-            for layer_collection in laycol_iter:
-                apply_function(layer_collection)
+        for child_list in child_lists:
+            for child in child_list:
+                apply_function(child)
 
-                if len(layer_collection.children) > 0:
-                    new_laycol_iter_list.append(layer_collection.children)
+                if child.children:
+                    new_child_lists.append(child.children)
 
-        laycol_iter_list = new_laycol_iter_list
+        child_lists = new_child_lists
 
 
 def isolate_rto(cls, self, view_layer, rto, *, children=False):
@@ -371,3 +373,29 @@ def remove_collection(laycol, collection, context):
                 laycol = laycol["parent"]
 
             cm.cm_list_index = laycol["row_index"]
+
+
+def select_collection_objects(collection_index, collection_name, replace, nested):
+    if collection_index == 0:
+        target_collection = bpy.context.view_layer.layer_collection.collection
+
+    else:
+        laycol = layer_collections[collection_name]
+        target_collection = laycol["ptr"].collection
+
+    if replace:
+        bpy.ops.object.select_all(action='DESELECT')
+
+    selection_state = get_move_selection().isdisjoint(target_collection.objects)
+
+    def select_objects(collection):
+            for obj in collection.objects:
+                try:
+                    obj.select_set(selection_state)
+                except RuntimeError:
+                    pass
+
+    select_objects(target_collection)
+
+    if nested:
+        apply_to_children(target_collection, select_objects)
diff --git a/object_collection_manager/operators.py b/object_collection_manager/operators.py
index 46e83023..7509d3f2 100644
--- a/object_collection_manager/operators.py
+++ b/object_collection_manager/operators.py
@@ -65,6 +65,7 @@ from .operator_utils import (
     clear_swap,
     link_child_collections_to_parent,
     remove_collection,
+    select_collection_objects,
 )
 
 class SetActiveCollection(Operator):
@@ -215,6 +216,58 @@ class ExpandSublevelOperator(Operator):
         return {'FINISHED'}
 
 
+class CMSelectCollectionObjectsOperator(Operator):
+    bl_label = "Select All Objects in the Collection"
+    bl_description = (
+        "  * LMB - Select all objects in collection.\n"
+        "  * Shift+LMB - Add/Remove collection objects from selection.\n"
+        "  * Ctrl+LMB - Isolate nested selection.\n"
+        "  * Ctrl+Shift+LMB - Add/Remove nested from selection"
+        )
+    bl_idname = "view3d.select_collection_objects"
+    bl_options = {'REGISTER', 'UNDO'}
+
+    collection_index: IntProperty()
+    collection_name: StringProperty()
+
+    def invoke(self, context, event):
+        modifiers = get_modifiers(event)
+
+        if modifiers == {"shift"}:
+            select_collection_objects(
+                collection_index=self.collection_index,
+                collection_name=self.collection_name,
+                replace=False,
+                nested=False
+                )
+
+        elif modifiers == {"ctrl"}:
+            select_collection_objects(
+                collection_index=self.collection_index,
+                collection_name=self.collection_name,
+                replace=True,
+                nested=True
+                )
+
+        elif modifiers == {"ctrl", "shift"}:
+            select_collection_objects(
+                collection_index=self.collection_index,
+                collection_name=self.collection_name,
+                replace=False,
+                nested=True
+                )
+
+        else:
+            select_collection_objects(
+                collection_index=self.collection_index,
+                collection_name=self.collection_name,
+                replace=True,
+                nested=False
+                )
+
+        return {'FINISHED'}
+
+
 class CMSetCollectionOperator(Operator):
     bl_label = "Set Object Collection"
     bl_description = (
diff --git a/object_collection_manager/qcd_operators.py b/object_collection_manager/qcd_operators.py
index 4f5f555a..4ffec562 100644
--- a/object_collection_manager/qcd_operators.py
+++ b/object_collection_manager/qcd_operators.py
@@ -45,6 +45,7 @@ from .internals import (
 
 from .operator_utils import (
     apply_to_children,
+    select_collection_objects,
 )
 
 
@@ -157,19 +158,32 @@ class ViewMoveQCDSlot(Operator):
         if modifiers == {"shift"}:
             bpy.ops.view3d.view_qcd_slot(slot=self.slot, toggle=True)
 
-            return {'FINISHED'}
-
         elif modifiers == {"ctrl"}:
             bpy.ops.view3d.move_to_qcd_slot(slot=self.slot, toggle=False)
-            return {'FINISHED'}
 
         elif modifiers == {"ctrl", "shift"}:
             bpy.ops.view3d.move_to_qcd_slot(slot=self.slot, toggle=True)
-            return {'FINISHED'}
+
+        elif modifiers == {"alt"}:
+            select_collection_objects(
+                collection_index=None,
+                collection_name=qcd_slots.get_name(self.slot),
+                replace=True,
+                nested=False
+                )
+
+        elif modifiers == {"alt", "shift"}:
+            select_collection_objects(
+                collection_index=None,
+                collection_name=qcd_slots.get_name(self.slot),
+                replace=False,
+                nested=False
+                )
 
         else:
             bpy.ops.view3d.view_qcd_slot(slot=self.slot, toggle=False)
-            return {'FINISHED'}
+
+        return {'FINISHED'}
 
 class ViewQCDSlot(Operator):
     '''View objects in QCD slot'''