--- a
+++ b/app/resources/b3d/bvh_reader.py
@@ -0,0 +1,211 @@
+class BVH(object):
+	
+
+	def __init__(self):
+		super(BVH, self).__init__()
+		self.root = []
+		self.channel_values = []
+		self.channel_dict = {}
+		self.position_values = []
+		self.position_dict = {}
+
+		self.display_frame = 2000
+
+
+	def load_from_file(self, bvh_file_path):
+		bvh_file = open(bvh_file_path, 'r')
+		bvh_str = bvh_file.read()
+
+		self.tokens = self.tokenize(bvh_str)
+		if len(self.tokens) == 0:
+			return False
+		self.token_index = 0
+
+		if not self.parse_hierarchy():
+			return False
+		if not self.parse_motion():
+			return False
+
+		bvh_file.close()
+		return True
+
+
+	def tokenize(self, source):
+		import re, os
+		# split source string with either white spaces, line separators, or tabulations
+		if (os.name == "posix"):
+			tokens = re.split(' |\n|\r\n|\t', source) #linux
+		else:
+			tokens = re.split(' |\n|\t', source) # windows
+		# filter the token list, remove all empty strings
+		return filter(None, tokens)
+
+
+	def parse_hierarchy(self):
+		if self.tokens[self.token_index] != 'HIERARCHY':
+			print('keyword HIERARCHY not found')
+			return False
+		self.token_index += 1
+		self.joint_count = 0
+		# parse all roots to support multiple hierarchy
+		while self.tokens[self.token_index] == 'ROOT':
+			joint = self.read_joint()
+			if joint:
+				self.root.append(joint)
+		return True
+
+
+	def parse_motion(self):
+		if self.tokens[self.token_index] != 'MOTION':
+			return False
+		self.token_index += 1
+		if self.tokens[self.token_index] != 'Frames:':
+			print('keyword Frames: not found')
+			return False
+		self.token_index += 1
+		try:
+			self.frame_count = int(self.tokens[self.token_index])
+		except ValueError:
+			print('frame count invalid')
+			return False
+		self.token_index += 1
+		# Frame Time: is treated as two tokens
+		if self.tokens[self.token_index] != 'Frame' or self.tokens[self.token_index + 1] != 'Time:':
+			print('keyword Frame Time: not found')
+			return False
+		self.token_index += 2
+		try:
+			self.frame_time = float(self.tokens[self.token_index])
+		except ValueError:
+			print('frame time invalid')
+			return False
+		self.token_index += 1
+		for i in range(self.frame_count):
+			for j in range(len(self.channel_values)):
+				try:
+					self.channel_values[j].append(float(self.tokens[self.token_index]))
+					self.token_index += 1
+				except ValueError:
+					print('frame data invalid', self.tokens[self.token_index])
+					return False
+		return True
+		
+
+	# before reading a joint, the token index will be pointing to the keyword ROOT,
+	# JOINT, or End
+	#
+	# after reading a joint, the token index will point to the token right after
+	# the closing brace of the joint which has been read
+	#
+	# in case of invalid joint format, function will ignore this joint and return None
+	# and the token index will point to the token that breaks joint format
+	def read_joint(self):
+		# 0 for ROOT or JOINT, 1 for End Site
+		joint_type = 0
+		if self.tokens[self.token_index] == 'End':
+			joint_type = 1
+		self.token_index += 1
+		if joint_type == 0:
+			joint_name = self.tokens[self.token_index]
+		self.token_index += 1
+		if self.tokens[self.token_index] != '{':
+			print('open brace not found')
+			return None
+		self.token_index += 1
+		if self.tokens[self.token_index] != 'OFFSET':
+			print('keyword OFFSET not found')
+			return None
+		self.token_index += 1	
+		try:
+			joint_offset = [float(self.tokens[self.token_index]), float(self.tokens[self.token_index + 1]), float(self.tokens[self.token_index + 2])]
+		except ValueError:
+			print('offset value error')
+			return None
+		self.token_index += 3
+		if joint_type == 0:
+			if self.tokens[self.token_index] != 'CHANNELS':
+				print('keyword CHANNELS not found')
+				return None
+			self.token_index += 1
+			try:
+				joint_channel_count = int(self.tokens[self.token_index])
+			except ValueError:
+				print('channel count value error')
+				return None
+			self.token_index += 1
+			joint_channels = []
+			self.channel_dict[joint_name] = {}
+			for i in range(joint_channel_count):
+				joint_channels.append(self.tokens[self.token_index])
+				# channel data is stored in two data structures, a two-dimensional table which stores the channel values of each frame
+				# and a dictionary which stores the links between the joints and the indices in the value table
+				# in order to reference a channel value of a specifique joint at a specifique frame, one can do:
+				#
+				# self.channel_values[self.channel_dict[joint_name][channel_name]][frame]
+				#
+				# ==== NEED TO FIX LATER ====
+				#
+				# channel data structure is created when the channel part of a joint is parsed, it could happen that there is invalid
+				# format in the rest of the joint definition
+				# since a joint with invalid definition will be ignored, the created channel data structure also becomes invalid
+				# to fix this later, we could perform a rollback when joint reading is failed
+				self.channel_dict[joint_name][self.tokens[self.token_index]] = len(self.channel_values)
+				self.channel_values.append([])
+				self.token_index += 1
+			joint_children = []
+			while self.tokens[self.token_index] == 'JOINT' or self.tokens[self.token_index] == 'End':
+				child_joint = self.read_joint()
+				if child_joint:
+					joint_children.append(child_joint)
+		if self.tokens[self.token_index] != '}':
+			print('close brace not found : ', self.tokens[self.token_index])
+			return None
+		if joint_type == 0:
+			joint = Joint(joint_name, joint_offset, joint_channels, joint_children)
+			self.joint_count += 1
+		else:
+			joint = EndSite(joint_offset)
+		self.token_index += 1		
+		return joint
+
+
+class Node(object):
+	
+
+	def __init__(self, offset):
+		super(Node, self).__init__()
+		self.offset = offset
+
+
+	# def __str__(self):
+	# 	return ''
+
+
+class Joint(Node):
+	
+
+	def __init__(self, node_name, offset, channels, children):
+		super(Joint, self).__init__(offset)
+		self.name = node_name
+		self.channels = channels
+		self.children = children
+
+
+	# def __str__(self):
+	# 	res = self.name
+	# 	res += ' ['
+	# 	for joint in self.children:
+	# 		res += str(joint)
+	# 	res += '] '
+	# 	return res
+
+
+class EndSite(Node):
+	
+
+	def __init__(self, offset):
+		super(EndSite, self).__init__(offset)
+
+
+	# def __str__(self):
+	# 	return 'EndSite : ' + str(self.offset)