import bpy import json from mathutils import Vector from typing import Union, List, Dict import os # Define the structure of the DeepMimic skeleton child_dict = { "root": ["spine", "right_thigh", "left_thigh"], "spine": ["chest"], "chest": ["head", "right_upper_arm", "left_upper_arm"], "head": [], "right_upper_arm": ["right_lower_arm"], "right_lower_arm": ["right_hand"], "right_hand": [], "left_upper_arm": ["left_lower_arm"], "left_lower_arm": ["left_hand"], "left_hand": [], "right_thigh": ["right_shin"], "right_shin": ["right_foot"], "right_foot": [], "left_thigh": ["left_shin"], "left_shin": ["left_foot"], "left_foot": [], } # Joints used in the DM frame definition. joints = [ "seconds", "hip", "hip", "chest", "neck", "right hip", "right knee", "right ankle", "right shoulder", "right elbow", "left hip", "left knee", "left ankle", "left shoulder", "left elbow" ] # Order of which the DeepMimicSkeleton bones need to be added to frame data. bone_names = [ "chest", "head", "right_thigh", "right_shin", "right_foot", "right_upper_arm", "right_lower_arm", "left_thigh", "left_shin", "left_foot", "left_upper_arm", "left_lower_arm" ] # All 1D joints joints_1d = ["right_shin", "left_shin", "right_lower_arm", "left_lower_arm"] # Define ankles in order to do correct quaternion adjustment. ankles = ["right_foot", "left_foot"] class BoneConstructionData: def __init__(self, target_name: str, inherit_bone_length: bool, inherit_bone_pos: bool, use_connect: bool, bone_direction_vec: List[float] = [0.0, 0.0, 1.0], use_IK: bool = False, use_DT: bool = False, IK_chain_length: int = 0): self.target_name = target_name self.inherit_bone_length = inherit_bone_length self.inherit_bone_pos = inherit_bone_pos self.use_connect = use_connect self.bone_direction_vec = bone_direction_vec self.use_IK = use_IK self.use_DT = use_DT self.IK_chain_length = IK_chain_length class BvhToDMSettings: def __init__(self, bonedict: Dict[str, BoneConstructionData], target_name: str): self.bonedict = bonedict self.child_dict = child_dict self.target_name = target_name self.skel_name = "DeepMimicSkeleton" self.translation_scale = 1.0 self.output_path = os.path.dirname(os.path.realpath(__file__)) self.output_file_name = "output.txt" class BvhToDM: def __init__(self, settings: BvhToDMSettings): self.settings = settings @staticmethod def tail_relative(bone, rel_vec: List[float]): bone.tail = [bone.head[x] + rel_vec[x] for x in range(3)] def find_parent(self, bone_name) -> Union[str, None]: for bone in self.settings.child_dict.keys(): if bone_name in self.settings.child_dict[bone]: return bone return None def find_child(self, bone_name) -> Union[str, None]: result = self.settings.child_dict[bone_name] if len(result) == 1: return result[0] else: return None def generate_humanoid_skeleton(self): # First fill up dictionary with edit_bone positions # (Since it seems to be difficult to read the edit_bones of an armature while editing another one...) target_bone_head_dict = {} bpy.data.objects[self.settings.target_name].select_set(True) if bpy.ops.object.mode_set.poll(): bpy.ops.object.mode_set(mode='EDIT') for edit_bone in bpy.context.object.data.edit_bones: target_bone_head_dict[edit_bone.name] = [x for x in edit_bone.head] bpy.ops.object.mode_set(mode='OBJECT') # Add the armature bpy.ops.object.armature_add(enter_editmode=True) obj = bpy.data.objects["Armature"] obj.name = self.settings.skel_name # Rename armature armature = obj.data armature.name = self.settings.skel_name # Delete first auto-generated bone bpy.ops.armature.select_all(action='SELECT') bpy.ops.armature.delete() # Cosntruct skeleton for bone_name in self.settings.bonedict.keys(): construction_data = self.settings.bonedict[bone_name] if bone_name == "root": root = armature.edit_bones.new("root") root.tail = (0.0, 0.0, 0.001) else: bone = armature.edit_bones.new(bone_name) parent = self.find_parent(bone_name) if parent is not None: bone.parent = armature.edit_bones[parent] bone.use_connect = construction_data.use_connect if construction_data.inherit_bone_pos: bone.head = target_bone_head_dict[construction_data.target_name] if construction_data.inherit_bone_length: length = bpy.data.objects[self.settings.target_name].data.bones[construction_data.target_name].length self.tail_relative(bone, [length * x for x in construction_data.bone_direction_vec]) else: # TODO: find out some way to guess the correct bone lengths if there are no corresponding bones in the target armature... if bone_name in ["spine", "chest", "head"]: self.tail_relative(bone, [0.0, 0.0, 0.22]) pass def constrain_DM_skeleton(self): if bpy.ops.object.mode_set.poll(): bpy.ops.object.mode_set(mode='POSE') # Note that pose_bones are under: bpy.data.objects[...].pose.bones skel = bpy.data.objects[self.settings.skel_name] # Root root_con = skel.pose.bones['root'].constraints.new('COPY_TRANSFORMS') root_con.target = bpy.data.objects[self.settings.target_name] root_con.subtarget = self.settings.bonedict['root'].target_name # Spine spine_con = skel.pose.bones['spine'].constraints.new('COPY_ROTATION') spine_con.target = bpy.data.objects[self.settings.target_name] spine_con.subtarget = self.settings.bonedict['spine'].target_name # Fixing rotation in elbow and knee joints: # 1) limit rotation constraint # 2) y- and z-rotations constrain from 0 to 0 degrees. "Fixed" # 3) Elbows: limit rotation in "Local space" from -180 to 0 degrees. # Knees: from 0 to 180 degrees # Knees rightshin = skel.pose.bones['right_shin'] rightshin.ik_max_x = 3.1415 rightshin.ik_min_x = 0 rightshin.use_ik_limit_x = True rightshin.lock_ik_y = True rightshin.lock_ik_z = True rightshin.rotation_mode = 'AXIS_ANGLE' leftshin = skel.pose.bones['left_shin'] leftshin.ik_max_x = 3.1415 leftshin.ik_min_x = 0 leftshin.use_ik_limit_x = True leftshin.lock_ik_y = True leftshin.lock_ik_z = True leftshin.rotation_mode = 'AXIS_ANGLE' # Elbows right_lower_arm = skel.pose.bones['right_lower_arm'] right_lower_arm.ik_max_x = 0 right_lower_arm.ik_min_x = -3.1415 right_lower_arm.use_ik_limit_x = True right_lower_arm.lock_ik_y = True right_lower_arm.lock_ik_z = True right_lower_arm.rotation_mode = 'AXIS_ANGLE' left_lower_arm = skel.pose.bones['left_lower_arm'] left_lower_arm.ik_max_x = 0 left_lower_arm.ik_min_x = -3.1415 left_lower_arm.use_ik_limit_x = True left_lower_arm.lock_ik_y = True left_lower_arm.lock_ik_z = True left_lower_arm.rotation_mode = 'AXIS_ANGLE' # IK settings skel.pose.ik_solver = "ITASC" skel.pose.ik_param.mode = "SIMULATION" def _scale_skeleton(self): """Old method: do not use. """ # Scale so that the distance from ankle to shoulders is the same # Set both objects to edit mode if bpy.ops.object.mode_set.poll(): bpy.ops.object.mode_set(mode='EDIT') shoulder_DM = "right_upper_arm" shoulder_mocap = "ShoulderRight" ankle_DM = "right_foot" ankle_mocap = "AnkleRight" DMS = bpy.data.armatures['DeepMimicSkeleton'] mocap_skel = bpy.data.armatures['rotation_prob'] # Only take into account z-component mocap_height = mocap_skel.bones[shoulder_mocap].head_local[2] - mocap_skel.bones[ankle_mocap].head_local[2] DM_height = DMS.bones[shoulder_DM].head_local[2] - DMS.bones[ankle_DM].head_local[2] scale_factor = mocap_height/DM_height # Select all bones bpy.data.objects['DMS'].select_set(True) bpy.ops.armature.select_all(action='SELECT') # Scale bpy.ops.transform.resize(value=(scale_factor, scale_factor, scale_factor)) def damped_track(self, bone: str, target_bone: str): constraint = bpy.data.objects[self.settings.skel_name].pose.bones[bone].constraints.new('DAMPED_TRACK') constraint.target = bpy.data.objects[self.settings.target_name] constraint.subtarget = target_bone constraint.head_tail = 1.0 def follow_mocap_damped_tracks(self): for bone in self.settings.bonedict.keys(): bone_data = self.settings.bonedict[bone] if bone_data.use_DT: self.damped_track(bone, bone_data.target_name) def inverse_kinematic_constraint(self, bone: str, target_bone: str, chain_count: int): constraint = bpy.data.objects[self.settings.skel_name].pose.bones[bone].constraints.new('IK') constraint.target = bpy.data.objects[self.settings.target_name] constraint.subtarget = target_bone constraint.use_tail = True constraint.use_location = True constraint.use_stretch = True constraint.iterations = 500 constraint.chain_count = chain_count def follow_mocap_IK(self): for bone in self.settings.bonedict.keys(): bone_data = self.settings.bonedict[bone] if bone_data.use_IK: self.inverse_kinematic_constraint( bone, self.settings.bonedict[self.find_child(bone)].target_name, bone_data.IK_chain_length ) # TODO: find out why these adjustments are necessary. # Probably has to do with: # 1) In which direction the bone's rest position is defined. # 2) The difference in worldframes. (Different axes between Blender and DeepMimic.) @staticmethod def quat_bvh_to_DM(quat): # transform x -> -z and z -> -x, except for ankles and root! return [quat[0], -quat[3], -quat[2], -quat[1]] @staticmethod def quat_bvh_to_DM_ankles(quat): # transform x -> -z and z -> x return [quat[0], quat[3], -quat[2], quat[1]] @staticmethod def quat_bvh_to_DM_root(quat): return [quat[0], quat[3], quat[2], -quat[1]] @staticmethod def pos_blender_DM(pos, scale): # y -> z, z -> -y? return [-scale*pos[1], scale*pos[2], -scale*pos[0]] def generate_frame(self, translation_scale): arm = bpy.data.objects[self.settings.skel_name] result = [] result.append(1.0 / bpy.context.scene.render.fps) pos = self.pos_blender_DM(arm.pose.bones['root'].head, translation_scale) result.extend(pos) root_quat = self.quat_bvh_to_DM_root(arm.pose.bones['root'].rotation_quaternion) result.extend(root_quat) for bone_name in bone_names: if bone_name in joints_1d: # invert knee angles (no clue why) if bone_name in joints_1d[:2]: angle = -arm.pose.bones[bone_name].rotation_axis_angle[0] else: angle = arm.pose.bones[bone_name].rotation_axis_angle[0] result.append(angle) else: # TODO: these rotations are absolute rotations! But we need local rotations... In the local bone frame... if bone_name in ankles: quat_DM = self.quat_bvh_to_DM_ankles(arm.pose.bones[bone_name].rotation_quaternion) else: quat_DM = self.quat_bvh_to_DM(arm.pose.bones[bone_name].rotation_quaternion) result.extend([x for x in quat_DM]) return result def generate_frames(self, translation_scale): if bpy.ops.object.mode_set.poll(): bpy.ops.object.mode_set(mode='EDIT') # Select all bones bpy.data.objects[self.settings.skel_name].select_set(True) bpy.ops.armature.select_all(action='SELECT') if bpy.ops.object.mode_set.poll(): bpy.ops.object.mode_set(mode='POSE') frames = [] loopText = "none" for frame in range(bpy.context.scene.frame_start, bpy.context.scene.frame_end + 1): # for frame in range(bpy.context.scene.frame_end + 1): bpy.context.scene.frame_set(frame) # Apply visual transform to pose bpy.ops.pose.visual_transform_apply() # bpy.context.view_layer.update() frames.append(self.generate_frame(translation_scale)) # Output in dictionary format for easy json dump outputDict = { "Loop": loopText, # "none" or "wrap" "Frames": frames } return json.dumps(outputDict, indent=4) def run(self): self.generate_humanoid_skeleton() self.constrain_DM_skeleton() self.follow_mocap_damped_tracks() self.follow_mocap_IK() # Save all quaternions in DeepMimic format, frame per frame! generated_text = self.generate_frames(self.settings.translation_scale) # print(generated_text) with open(self.settings.output_path + "/" + self.settings.output_file_name, "w") as output: output.write(generated_text)