feat: added initial gpencil modifer support

Related to https://gitlab.com/slumber/multi-user/-/issues/147

multi_user/bl_types/bl_object.py

@@ -271,13 +271,35 @@ class BlObject(BlDatablock):
             return data
 
         # MODIFIERS
-        if hasattr(instance, 'modifiers'):
+        modifiers = getattr(instance,'modifiers', None )
+        if modifiers:
             dumper.include_filter = None
             dumper.depth = 1
             data["modifiers"] = {}
-            for index, modifier in enumerate(instance.modifiers):
+            for index, modifier in enumerate(modifiers):
                 data["modifiers"][modifier.name] = dumper.dump(modifier)
 
+        gp_modifiers = getattr(instance, 'grease_pencil_modifiers', None)
+
+        if gp_modifiers:
+            dumper.include_filter = None
+            dumper.depth = 1
+            gp_modifiers_data = data["grease_pencil_modifiers"] = {}
+
+            for index, modifier in enumerate(gp_modifiers):
+                gp_mod_data = gp_modifiers_data[modifier.name] = dict()
+                gp_mod_data.update(dumper.dump(modifier))
+
+                if hasattr(modifier, 'use_custom_curve') \
+                        and modifier.use_custom_curve:
+                    curve_dumper = Dumper()
+                    curve_dumper.depth = 5
+                    curve_dumper.include_filter = [
+                        'curves',
+                        'points',
+                        'location']
+                    gp_mod_data['curve'] = curve_dumper.dump(modifier.curve)
+
         # CONSTRAINTS
         if hasattr(instance, 'constraints'):
             dumper.depth = 3

multi_user/bl_types/dump_anything.py

@@ -506,12 +506,14 @@ class Loader:
             T.ColorRampElement: (CONSTRUCTOR_NEW, ["position"]),
             T.ParticleSettingsTextureSlot: (CONSTRUCTOR_ADD, []),
             T.Modifier: (CONSTRUCTOR_NEW, ["name", "type"]),
+            T.GpencilModifier: (CONSTRUCTOR_NEW, ["name", "type"]),
             T.Constraint: (CONSTRUCTOR_NEW, ["type"]),
         }
 
         destructors = {
             T.ColorRampElement: DESTRUCTOR_REMOVE,
             T.Modifier: DESTRUCTOR_CLEAR,
+            T.GpencilModifier: DESTRUCTOR_CLEAR,
             T.Constraint: CONSTRUCTOR_NEW,
         }
         element_type = element.bl_rna_property.fixed_type
@@ -574,6 +576,7 @@ class Loader:
                     dst_curve.points[int(point_idx)].location = pos
                 else:
                     dst_curve.points.new(pos[0], pos[1])
+        curves.update()
 
     def _load_pointer(self, instance, dump):
         rna_property_type = instance.bl_rna_property.fixed_type