glTF exporter: manage delta transform animation

4 files changed, 63 insertions, 22 deletions

diff --git a/io_scene_gltf2/__init__.py b/io_scene_gltf2/__init__.py
index 3034595b..4fad230d 100755
--- a/io_scene_gltf2/__init__.py
+++ b/io_scene_gltf2/__init__.py
@@ -4,7 +4,7 @@
 bl_info = {
     'name': 'glTF 2.0 format',
     'author': 'Julien Duroure, Scurest, Norbert Nopper, Urs Hanselmann, Moritz Becher, Benjamin Schmithüsen, Jim Eckerlein, and many external contributors',
-    "version": (3, 4, 15),
+    "version": (3, 4, 16),
     'blender': (3, 3, 0),
     'location': 'File > Import-Export',
     'description': 'Import-Export as glTF 2.0',
diff --git a/io_scene_gltf2/blender/com/gltf2_blender_data_path.py b/io_scene_gltf2/blender/com/gltf2_blender_data_path.py
index a329193a..9aeeb5dc 100755
--- a/io_scene_gltf2/blender/com/gltf2_blender_data_path.py
+++ b/io_scene_gltf2/blender/com/gltf2_blender_data_path.py
@@ -15,20 +15,33 @@ def get_target_object_path(data_path: str) -> str:
         return ""
     return path_split[0]
 
-def get_rotation_modes(target_property: str) -> str:
+def get_rotation_modes(target_property: str):
     """Retrieve rotation modes based on target_property"""
     if target_property == "rotation_euler":
-        return True, False, ["XYZ", "XZY", "YXZ", "YZX", "ZXY", "ZYX"]
+        return True, ["XYZ", "XZY", "YXZ", "YZX", "ZXY", "ZYX"]
     elif target_property == "delta_rotation_euler":
-        return True, True, ["XYZ", "XZY", "YXZ", "YZX", "ZXY", "ZYX"]
+        return True, ["XYZ", "XZY", "YXZ", "YZX", "ZXY", "ZYX"]
     elif target_property == "rotation_quaternion":
-        return True, False, ["QUATERNION"]
+        return True, ["QUATERNION"]
     elif target_property == "delta_rotation_quaternion":
-        return True, True, ["QUATERNION"]
+        return True, ["QUATERNION"]
     elif target_property in ["rotation_axis_angle"]:
-        return True, False, ["AXIS_ANGLE"]
+        return True, ["AXIS_ANGLE"]
     else:
-        return False, False, []
+        return False, []
+
+def is_location(target_property):
+    return "location" in target_property
+
+def is_rotation(target_property):
+    return "rotation" in target_property
+
+def is_scale(target_property):
+    return "scale" in target_property
+
+def get_delta_modes(target_property: str) -> str:
+    """Retrieve location based on target_property"""
+    return target_property.startswith("delta_")
 
 def is_bone_anim_channel(data_path: str) -> bool:
     return data_path[:10] == "pose.bones"
\ No newline at end of file
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
index 3e67f1f7..e7235254 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
@@ -4,7 +4,7 @@
 import bpy
 import typing
 
-from ..com.gltf2_blender_data_path import get_target_object_path, get_target_property_name, get_rotation_modes
+from ..com.gltf2_blender_data_path import get_target_object_path, get_target_property_name, get_rotation_modes, get_delta_modes, is_location, is_rotation, is_scale
 from io_scene_gltf2.io.com import gltf2_io
 from io_scene_gltf2.io.com import gltf2_io_debug
 from io_scene_gltf2.blender.exp.gltf2_blender_gather_cache import cached
@@ -364,6 +364,8 @@ def __get_channel_groups(blender_action: bpy.types.Action, blender_object: bpy.t
     targets = {}
     multiple_rotation_mode_detected = False
     delta_rotation_detection = [False, False] # Normal / Delta
+    delta_location_detection = [False, False] # Normal / Delta
+    delta_scale_detection = [False, False]    # Normal / Delta
     for fcurve in blender_action.fcurves:
         # In some invalid files, channel hasn't any keyframes ... this channel need to be ignored
         if len(fcurve.keyframe_points) == 0:
@@ -405,24 +407,46 @@ def __get_channel_groups(blender_action: bpy.types.Action, blender_object: bpy.t
 
         # Detect that object or bone are not multiple keyed for euler and quaternion
         # Keep only the current rotation mode used by object
-        rotation, delta, rotation_modes = get_rotation_modes(target_property)
+        rotation, rotation_modes = get_rotation_modes(target_property)
+        delta = get_delta_modes(target_property)
 
         # Delta rotation management
-        if delta is False:
-            if delta_rotation_detection[1] is True: # normal rotation coming, but delta is already present
-                multiple_rotation_mode_detected = True
-                continue
-            delta_rotation_detection[0] = True
-        else:
-            if delta_rotation_detection[0] is True: # delta rotation coming, but normal is already present
+        if is_rotation(target_property) :
+            if delta is False:
+                if delta_rotation_detection[1] is True: # normal rotation coming, but delta is already present
+                    continue
+                delta_rotation_detection[0] = True
+            else:
+                if delta_rotation_detection[0] is True: # delta rotation coming, but normal is already present
+                    continue
+                delta_rotation_detection[1] = True
+
+
+            if rotation and target.rotation_mode not in rotation_modes:
                 multiple_rotation_mode_detected = True
                 continue
-            delta_rotation_detection[1] = True
 
+        # Delta location management
+        if is_location(target_property):
+            if delta is False:
+                if delta_location_detection[1] is True: # normal location coming, but delta is already present
+                    continue
+                delta_location_detection[0] = True
+            else:
+                if delta_location_detection[0] is True: # delta location coming, but normal is already present
+                    continue
+                delta_location_detection[1] = True
 
-        if rotation and target.rotation_mode not in rotation_modes:
-            multiple_rotation_mode_detected = True
-            continue
+        # Delta scale management
+        if is_scale(target_property):
+            if delta is False:
+                if delta_scale_detection[1] is True: # normal scale coming, but delta is already present
+                    continue
+                delta_scale_detection[0] = True
+            else:
+                if delta_scale_detection[0] is True: # delta scale coming, but normal is already present
+                    continue
+                delta_scale_detection[1] = True
 
         # group channels by target object and affected property of the target
         target_properties = targets.get(target, {})
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
index 53d78945..b73c61b8 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
@@ -45,6 +45,7 @@ class Keyframe:
         length = {
             "delta_location": 3,
             "delta_rotation_euler": 3,
+            "delta_scale": 3,
             "location": 3,
             "rotation_axis_angle": 4,
             "rotation_euler": 3,
@@ -367,7 +368,10 @@ def gather_keyframes(blender_obj_uuid: str,
                             "rotation_axis_angle": [rot.to_axis_angle()[1], rot.to_axis_angle()[0][0], rot.to_axis_angle()[0][1], rot.to_axis_angle()[0][2]],
                             "rotation_euler": rot.to_euler(),
                             "rotation_quaternion": rot,
-                            "scale": sca
+                            "scale": sca,
+                            "delta_location": trans,
+                            "delta_rotation_euler": rot.to_euler(),
+                            "delta_scale": sca
                         }[target]
                 else:
                     key.value = get_sk_driver_values(driver_obj_uuid, frame, channels, export_settings)