fix: correct skin deformation and scale for GLB character models

The Miku model T-posed because the previous _update_skin() used
set_bone_pose(i, get_bone_pose(i)) which is a no-op when the pose
is unchanged. Replace with skeleton.notification(NOTIFICATION_UPDATE_SKELETON)
to force the Skeleton3D to recompute bone transforms and notify the
MeshInstance to update vertex buffers.

Also fix scale: the GLB is ~1.2m tall (not 1.6m as documented), so
set scale_factor=1.25 to fit the 1.8m player capsule, and add
position_y_offset=-0.2 to align the model's feet with the player origin.

Co-Authored-By: Hermes Agent <[email protected]>

characters/skinned_player_model.gd

@@ -5,9 +5,13 @@ class_name SkinnedPlayerModel
 ## Replaces the procedural HumanoidModel for characters with custom skins.
 
 @export var model_path: String = ""
-## Scale factor applied to the loaded scene. For the Miku GLB, 1.0 is correct (~1.6m).
+## Scale factor applied to the loaded scene. The current Miku GLB is ~1.2m tall;
+## set to 1.25 to reach ~1.5m (fits inside the 1.8m player capsule).
 ## For models exported in centimeters (Mixamo/Blender default), set to 0.01.
-@export var scale_factor: float = 1.0
+@export var scale_factor: float = 1.25
+## Vertical offset to align the model's visual feet with the player origin.
+## The Miku GLB has feet at Y=0.2 in rest pose; negative offset lowers them.
+@export var position_y_offset: float = -0.2
 @export var first_person_mode: bool = false  # Hide head/torso for FPS view
 
 ## Bones per second for locomotion animations created at runtime.
@@ -56,10 +60,11 @@ func load_model(path: String) -> void:
 	add_child(scene)
 	print("SkinnedPlayerModel: scene added: %s" % scene.name)
 
-	# Apply model scale (the Miku GLB is already in meters, ~1.6m tall)
+	# Apply model scale (the Miku GLB is ~1.2m; scale_factor adjusts to target height)
 	# For models exported in centimeters (common from Mixamo/Blender), set scale_factor to 0.01.
 	scene.scale = Vector3(scale_factor, scale_factor, scale_factor)
-	print("SkinnedPlayerModel: applied scale %.4f" % scale_factor)
+	scene.position = Vector3(0, position_y_offset * scale_factor, 0)
+	print("SkinnedPlayerModel: applied scale %.4f, y_offset %.4f" % [scale_factor, position_y_offset])
 
 	# Find mesh instance for first-person mode
 	_mesh_instance = scene.find_child("Tda Miku for fbx_mesh", true, false)
@@ -122,6 +127,10 @@ func load_model(path: String) -> void:
 
 		# Ensure fallback animations exist for states the movement system needs
 		_ensure_locomotion_animations(animation_player)
+
+		# Force initial skin update so the first rendered frame shows the
+		# correct animated pose instead of T-pose.
+		_update_skin()
 	else:
 		print("SkinnedPlayerModel: WARNING - no AnimationPlayer found")
 
@@ -303,16 +312,12 @@ func _add_animation_to_player(ap: AnimationPlayer, anim_name: String, anim: Anim
 	print("SkinnedPlayerModel: added '%s' (%d tracks)" % [anim_name, anim.get_track_count()])
 
 func _update_skin() -> void:
-	## Force skeleton skin update by re-applying current bone poses.
+	## Force skeleton skin update by notifying Skeleton3D that poses changed.
-	## GLTF runtime loaded models sometimes need this because the AnimationPlayer's
+	## GLTF runtime loaded models need this because AnimationPlayer's internal
-	## internal bone pose updates don't always trigger the visual pipeline.
+	## bone pose updates don't always trigger the visual pipeline's dirty flags.
-	# Re-apply current bone poses to ensure dirty flags are set.
+	## NOTIFICATION_UPDATE_SKELETON causes the Skeleton3D to recompute its
-	# This triggers NOTIFICATION_UPDATE_SKELETON on the Skeleton3D.
+	## bone transforms and notify attached MeshInstances to update vertex buffers.
-	for i in range(skeleton.get_bone_count()):
+	skeleton.notification(NOTIFICATION_UPDATE_SKELETON)
-		skeleton.set_bone_pose(i, skeleton.get_bone_pose(i))
-	# Also notify the MeshInstance that its skeleton changed
-	if _mesh_instance:
-		_mesh_instance.skeleton = _mesh_instance.skeleton
 
 func _setup_first_person() -> void:
 	# In first person, hide the head and upper body so only arms/hands/legs show

debug/test_level_builder.gd

@@ -433,7 +433,8 @@ func _spawn_player(pid: int) -> CharacterBody3D:
 		var skinned = load("res://characters/skinned_player_model.gd").new()
 		skinned.name = "SkinnedModel"
 		skinned.model_path = "res://assets/characters/skins/miku_rigged_animated.glb"
-		skinned.scale_factor = 1.0  # Already scaled to 1.8m in Blender
+		skinned.scale_factor = 1.25  # GLB is ~1.2m, scale to ~1.5m for player capsule
+		skinned.position_y_offset = -0.2  # Align feet with player origin
 		skinned.position = Vector3.ZERO  # Model origin = player origin
 		player.add_child(skinned)
 		print("TestLevelBuilder: added SkinnedModel for player 1")

scenes/maps/level_runtime.gd

@@ -148,6 +148,8 @@ func _spawn_player(pid: int) -> CharacterBody3D:
 		var skinned = load("res://characters/skinned_player_model.gd").new()
 		skinned.name = "SkinnedModel"
 		skinned.model_path = "res://assets/characters/skins/miku_rigged_animated.glb"
+		skinned.scale_factor = 1.25
+		skinned.position_y_offset = -0.2
 		skinned.position = Vector3(0, 0.0, 0)
 		skinned.first_person_mode = true
 		player.add_child(skinned)