Implement type 'Angle', packet 'EntityLookPacket' and fix Packet Types

Remarks: I chose to implement an angle between 0-360 degrees as opposed to -180 - 180. linear transformation, the maths was far simpler converting an UnsignedByte into positive values instead of a Byte into negative and positive

minecraft/networking/packets/clientbound/play/__init__.py

@@ -5,6 +5,7 @@ from minecraft.networking.packets import (
 from minecraft.networking.types import (
     Integer, FixedPointInteger, UnsignedByte, Byte, Boolean, UUID, Short,
     VarInt, Double, Float, String, Enum, Difficulty, Dimension, GameMode,
+    Angle
 )
 
 from .combat_event_packet import CombatEventPacket
@@ -40,6 +41,7 @@ def get_packets(context):
         RespawnPacket,
         PluginMessagePacket,
         PlayerListHeaderAndFooterPacket,
+        EntityLookPacket
     }
     if context.protocol_version <= 47:
         packets |= {
@@ -178,8 +180,8 @@ class SpawnPlayerPacket(Packet):
         else {'y': FixedPointInteger},
         {'z': Double} if context.protocol_version >= 100
         else {'z': FixedPointInteger},
-        {'yaw': Float},
-        {'pitch': Float},
+        {'yaw': Angle},
+        {'pitch': Angle},
         # TODO: read entity metadata
         {'current_item': Short} if context.protocol_version <= 49 else {}
     ])
@@ -296,3 +298,22 @@ class PlayerListHeaderAndFooterPacket(Packet):
     definition = [
         {'header': String},
         {'footer': String}]
+
+
+class EntityLookPacket(Packet):
+    @staticmethod
+    def get_id(context):
+        return 0x2A if context.protocol_version >= 389 else \
+               0x29 if context.protocol_version >= 345 else \
+               0x28 if context.protocol_version >= 318 else \
+               0x27 if context.protocol_version >= 94 else \
+               0x28 if context.protocol_version >= 70 else \
+               0x16
+
+    packet_name = 'entity look'
+    definition = [
+        {'entity_id': VarInt},
+        {'yaw': Angle},
+        {'pitch': Angle},
+        {'on_ground': Boolean}
+    ]

minecraft/networking/packets/clientbound/play/spawn_object_packet.py

@@ -2,7 +2,7 @@ from minecraft.networking.packets import Packet
 from minecraft.networking.types.utility import descriptor
 
 from minecraft.networking.types import (
-    VarInt, UUID, Byte, Double, Integer, UnsignedByte, Short, Enum, Vector,
+    VarInt, UUID, Byte, Double, Integer, Angle, Short, Enum, Vector,
     PositionAndLook, attribute_alias, multi_attribute_alias,
 )
 
@@ -103,7 +103,7 @@ class SpawnObjectPacket(Packet):
         for attr in 'x', 'y', 'z':
             setattr(self, attr, xyz_type.read(file_object))
         for attr in 'pitch', 'yaw':
-            setattr(self, attr, UnsignedByte.read(file_object))
+            setattr(self, attr, Angle.read(file_object))
 
         self.data = Integer.read(file_object)
         if self.context.protocol_version >= 49 or self.data > 0:
@@ -125,7 +125,7 @@ class SpawnObjectPacket(Packet):
         for coord in self.x, self.y, self.z:
             xyz_type.send(coord, packet_buffer)
         for coord in self.pitch, self.yaw:
-            UnsignedByte.send(coord, packet_buffer)
+            Angle.send(coord, packet_buffer)
 
         Integer.send(self.data, packet_buffer)
         if self.context.protocol_version >= 49 or self.data > 0:

minecraft/networking/types/basic.py

@@ -11,9 +11,10 @@ from .utility import Vector
 
 __all__ = (
     'Type', 'Boolean', 'UnsignedByte', 'Byte', 'Short', 'UnsignedShort',
-    'Integer', 'FixedPointInteger', 'VarInt', 'Long', 'UnsignedLong', 'Float',
-    'Double', 'ShortPrefixedByteArray', 'VarIntPrefixedByteArray',
-    'TrailingByteArray', 'String', 'UUID', 'Position',
+    'Integer', 'FixedPointInteger', 'Angle', 'VarInt', 'Long',
+    'UnsignedLong', 'Float', 'Double', 'ShortPrefixedByteArray',
+    'VarIntPrefixedByteArray', 'TrailingByteArray', 'String', 'UUID',
+    'Position',
 )
 
 
@@ -117,6 +118,17 @@ class FixedPointInteger(Type):
         Integer.send(int(value * 32), socket)
 
 
+class Angle(Type):
+    @staticmethod
+    def read(file_object):
+        # Linearly transform angle in steps of 1/256 into steps of 1/360
+        return 360 * UnsignedByte.read(file_object) / 255
+
+    def send(value, socket):
+        # Normalize angle between 0 and 255 and convert to int.
+        UnsignedByte.send(int(255 * (value / 360)), socket)
+
+
 class VarInt(Type):
     @staticmethod
     def read(file_object):
@@ -311,3 +323,4 @@ class Position(Type, Vector):
                  if context.protocol_version >= 443 else
                  (x & 0x3FFFFFF) << 38 | (y & 0xFFF) << 26 | (z & 0x3FFFFFF))
         UnsignedLong.send(value, socket)
+