store / restore values with a context manager

OP_animate_path.py

@@ -2,6 +2,7 @@ import bpy
 from . import fn
 from mathutils import Vector, Euler
 from mathutils.geometry import intersect_line_plane
+
 ## step 2 : Auto animate the path (with feet selection) and modal to adjust speed
 
 def get_bone_transform_at_frame(b, act, frame):
@@ -41,6 +42,7 @@ def anim_path_from_translate():
     #     return ('ERROR', 'No "foot" in active bone name\n-> Select foot that has the most reliable contact')
     settings = bpy.context.scene.anim_cycle_settings
     axis = settings.forward_axis
+    
     curve = None
     if settings.path_to_follow:
         curve = settings.path_to_follow
@@ -161,7 +163,6 @@ def anim_path_from_translate():
             if fcu.data_path == 'eval_time':
                 curve.data.animation_data.action.fcurves.remove(fcu)
                 break
-    
     ## add eval time animation on curve
     anim_frame = settings.start_frame
     curve.data.path_duration = frame_duration

OP_expand_cycle_step.py

@@ -1,6 +1,7 @@
 import bpy, re
 from . import fn
 from time import time
+
 ## step 3
 # - Bake cycle modifier keys -chained with- step the animation path
 # - Pin the feet (separated ops)
@@ -227,6 +228,12 @@ class UAC_OT_bake_cycle_and_step(bpy.types.Operator):
         return {"FINISHED"}
 
 
+# detect contact key
+# [ 'array_index', 'auto_smoothing', 'bl_rna', 'color', 'color_mode', 'convert_to_keyframes', 'convert_to_samples', 'data_path',
+#  'driver', 'evaluate', 'extrapolation', 'group', 'hide', 'is_empty', 'is_valid', 'keyframe_points', 'lock', 'modifiers', 'mute',
+#  'range', 'rna_type', 'sampled_points', 'select', 'update', 'update_autoflags']
+
+
 def pin_down_feets():
     print(fn.helper())
     obj = bpy.context.object
@@ -241,36 +248,32 @@ def pin_down_feets():
         return ('ERROR', f'No action on {obj.name}')
     print('action', act.name)
 
-    # detect contact key
-    # [ 'array_index', 'auto_smoothing', 'bl_rna', 'color', 'color_mode', 'convert_to_keyframes', 'convert_to_samples', 'data_path',
-    #  'driver', 'evaluate', 'extrapolation', 'group', 'hide', 'is_empty', 'is_valid', 'keyframe_points', 'lock', 'modifiers', 'mute',
-    #  'range', 'rna_type', 'sampled_points', 'select', 'update', 'update_autoflags']
-
     act = obj.animation_data.action
-    org_frame = bpy.context.scene.frame_current
-    
-    # TODO autodetect contact frame ?
 
+    to_change_list = [
+        (bpy.context.scene, 'frame_current', '_undefined'), # use '_undefined' when no value to assign for now
+        (bpy.context.scene.render, 'use_simplify', True),
+        (bpy.context.scene.render, 'simplify_subdivision', 0),
+    ]
     ## Link armature in a new collection and exclude all the others
 
-    ## STORE AND MODIFY /-
+    ## STORE for context manager store/restore  /-
+    tmp_col = bpy.data.collections.get('TMP_COLLECTION_PINNING')
+    if not tmp_col:
         tmp_col = bpy.data.collections.new('TMP_COLLECTION_PINNING')
+    if tmp_col.name not in bpy.context.scene.collection.children:
         bpy.context.scene.collection.children.link(tmp_col)
+    if obj not in tmp_col.objects[:]:
         tmp_col.objects.link(obj)
 
-    simplify = bpy.context.scene.render.use_simplify
-    simplify_subdiv = bpy.context.scene.render.simplify_subdivision
-    bpy.context.scene.render.use_simplify = True
-    bpy.context.scene.render.simplify_subdivision = 0
-
-    showed_col = []
     for vlc in bpy.context.view_layer.layer_collection.children:
         if vlc.collection == tmp_col:
             continue
-        showed_col.append([vlc, vlc.exclude])
+        to_change_list.append((vlc, 'exclude', True))
-        vlc.exclude = True
+    
     #-/
 
+    with fn.attr_set(to_change_list):
         t0 = time()
         ct = 0
         done = {}
@@ -294,7 +297,7 @@ def pin_down_feets():
             for k in fcu.keyframe_points:
 
                 if k.type == 'EXTREME':
-                bpy.context.scene.frame_set(k.co[0])
+                    bpy.context.scene.frame_set(int(k.co[0]))
                     if start_contact is None:
                         start_contact=k.co[0]
                         # record coordinate relative to referent object (or world coord)
@@ -356,16 +359,10 @@ def pin_down_feets():
     # with all collection excluded >> 433 keys changed in 25.00s
     # with simplify >> 9.57s
 
-    bpy.context.scene.render.use_simplify = simplify
-    bpy.context.scene.render.simplify_subdivision = simplify_subdiv
-
-    for exclude_pairs in showed_col:
-        exclude_pairs[0].exclude = exclude_pairs[1]
     tmp_col.objects.unlink(obj)
     bpy.data.collections.remove(tmp_col)
 
-    bpy.context.scene.frame_current = org_frame
+  
-    # detect last key in contact
 
 
 class UAC_OT_pin_feets(bpy.types.Operator):

README.md

@@ -39,6 +39,10 @@ Sidebar > Anim > unfold anim cycle
 
 ## Changelog:
 
+0.4.2
+
+- context manager for `expand cycle step` store / restore
+
 0.4.1
 
 - update fcurve after bake

__init__.py

@@ -2,7 +2,7 @@ bl_info = {
     "name": "Unfold Anim Cycle",
     "description": "Anim tools to develop walk/run cycles along a curve",
     "author": "Samuel Bernou",
-    "version": (0, 4, 1),
+    "version": (0, 4, 2),
     "blender": (3, 0, 0),
     "location": "View3D",
     "warning": "WIP",

fn.py

@@ -312,3 +312,26 @@ def update_action(act):
             if area.type == 'GRAPH_EDITOR':
                 area.tag_redraw()
 
+### --- context manager - store / restore
+
+
+class attr_set():
+    '''Receive a list of tuple [(data_path:python_obj, "attribute":str, "wanted value":str)]
+    before with statement : Store existing values, assign wanted value 
+    after with statement: Restore values to their old values
+    '''
+
+    def __init__(self, attrib_list):
+        self.store = []
+        for prop, attr, new_val in attrib_list:
+            self.store.append( (prop, attr, getattr(prop, attr)) )
+            if new_val == '_undefined': # None -> what if we want to apply None state ?
+                continue
+            setattr(prop, attr, new_val)
+          
+    def __enter__(self):
+        return self
+      
+    def __exit__(self, exc_type, exc_value, exc_traceback):
+        for prop, attr, old_val in self.store:
+            setattr(prop, attr, old_val)