def can_jump(self, y_distance=5) -> bool:
"""
Method that looks to see if there is a floor under
the player_sprite. If there is a floor, the player can jump
and we return a True.
:returns: True if there is a platform below us
:rtype: bool
"""
# Check for touching a ladder
if self.is_on_ladder():
return False
# Move down to see if we are on a platform
self.player_sprite.center_y -= y_distance
# Check for wall hit
hit_list = check_for_collision_with_list(self.player_sprite, self.platforms)
self.player_sprite.center_y += y_distance
if len(hit_list) > 0:
self.jumps_since_ground = 0
if len(hit_list) > 0 or self.allow_multi_jump and self.jumps_since_ground < self.allowed_jumps:
return True
else:
return False
def is_on_ladder(self):
# Check for touching a ladder
if self.ladders:
hit_list = check_for_collision_with_list(self.player_sprite, self.ladders)
if len(hit_list) > 0:
return True
return False
def can_jump(self) -> bool:
"""
Method that looks to see if there is a floor under
the player_sprite. If there is a floor, the player can jump
and we return a True.
:returns: True if there is a platform below us
:rtype: bool
"""
# --- Move in the y direction
self.player_sprite.center_y -= 2
# Check for wall hit
hit_list = check_for_collision_with_list(self.player_sprite,
self.platforms)
self.player_sprite.center_y += 2
if len(hit_list) > 0:
self.jumps_since_ground = 0
if len(
hit_list
) > 0 or self.allow_multi_jump and self.jumps_since_ground < self.allowed_jumps:
return True
else:
return False
def update(self):
"""
Move everything and resolve collisions.
"""
# --- Move in the x direction
self.player_sprite.center_x += self.player_sprite.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_x > 0:
for item in hit_list:
self.player_sprite.right = min(item.left,
self.player_sprite.right)
elif self.player_sprite.change_x < 0:
for item in hit_list:
self.player_sprite.left = max(item.right,
self.player_sprite.left)
else:
print("Error, collision while player wasn't moving.")
# --- Move in the y direction
self.player_sprite.center_y += self.player_sprite.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_y > 0:
for item in hit_list:
self.player_sprite.top = min(item.bottom,
self.player_sprite.top)
elif self.player_sprite.change_y < 0:
for item in hit_list:
self.player_sprite.bottom = max(item.top,
self.player_sprite.bottom)
else:
print("Error, collision while player wasn't moving.")
def update(self):
"""
Move everything and resolve collisions.
"""
# --- Move in the x direction
self.player_sprite.center_x += self.player_sprite.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_x > 0:
for item in hit_list:
self.player_sprite.right = min(item.left,
self.player_sprite.right)
elif self.player_sprite.change_x < 0:
for item in hit_list:
self.player_sprite.left = max(item.right,
self.player_sprite.left)
else:
print("Error, collision while player wasn't moving.")
# --- Move in the y direction
self.player_sprite.center_y += self.player_sprite.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_y > 0:
for item in hit_list:
self.player_sprite.top = min(item.bottom,
self.player_sprite.top)
elif self.player_sprite.change_y < 0:
for item in hit_list:
self.player_sprite.bottom = max(item.top,
self.player_sprite.bottom)
else:
print("Error, collision while player wasn't moving.")
def collides_with_list(self, sprite_list: list) -> list:
"""Check if current sprite is overlapping with any other sprite in a list
Args:
self: current Sprite
sprite_list: SpriteList to check against
Returns:
SpriteList of all overlapping Sprites from the original SpriteList
"""
from arcade.geometry import check_for_collision_with_list
return check_for_collision_with_list(self, sprite_list)
def update(self):
"""
Move everything and resolve collisions.
"""
# --- Move in the x direction
for char in self.characters:
char.center_x += char.change_x
# Check for wall hit
hit_list = check_for_collision_with_list(char, self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if char.change_x > 0:
for item in hit_list:
char.right = min(item.left, char.right)
elif char.change_x < 0:
for item in hit_list:
char.left = max(item.right, char.left)
else:
raise RuntimeError(
f"Error, collision while {char} wasn't moving.")
# --- Move in the y direction
char.center_y += char.change_y
# Check for wall hit
hit_list = check_for_collision_with_list(char, self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if char.change_y > 0:
for item in hit_list:
char.top = min(item.bottom, char.top)
elif char.change_y < 0:
for item in hit_list:
char.bottom = max(item.top, char.bottom)
else:
raise RuntimeError(
f"Error, collision while {char} wasn't moving.")
def update(self):
"""
Move os objetos, verifica e resolve as colisões.
"""
player_aux = copy.deepcopy(self.player_sprite)
"""
Movimentação do eixo X
"""
player_aux.center_x += player_aux.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(player_aux,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
self.player_sprite.change_x = 0
else:
self.player_sprite.center_x += self.player_sprite.change_x
"""
Movimentação do eixo Y
"""
player_aux.center_y += player_aux.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(player_aux,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
self.player_sprite.change_y = 0
else:
self.player_sprite.center_y += self.player_sprite.change_y
#Limpeza de variaveis
self.player_sprite.change_x = 0
self.player_sprite.change_y = 0
def can_jump(self) -> bool:
"""
Method that looks to see if there is a floor under
the player_sprite. If there is a floor, the player can jump
and we return a True.
"""
# --- Move in the y direction
self.player_sprite.center_y -= 2
# Check for wall hit
hit_list = check_for_collision_with_list(self.player_sprite, self.platforms)
result = False
if len(hit_list) > 0:
result = True
self.player_sprite.center_y += 2
return result
def can_jump(self) -> bool:
"""
Method that looks to see if there is a floor under
the player_sprite. If there is a floor, the player can jump
and we return a True.
"""
# --- Move in the y direction
self.player_sprite.center_y -= 2
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.platforms)
self.player_sprite.center_y += 2
if len(hit_list) > 0:
return True
else:
return False
def update(self):
"""
Move everything and resolve collisions.
"""
# print(f"Spot A ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
# --- Add gravity
self.player_sprite.change_y -= self.gravity_constant
# --- Move in the y direction
self.player_sprite.center_y += self.player_sprite.change_y
# Check for wall hit
hit_list = check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_y > 0:
for item in hit_list:
self.player_sprite.top = min(item.bottom,
self.player_sprite.top)
# print(f"Spot X ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
elif self.player_sprite.change_y < 0:
for item in hit_list:
while check_for_collision(self.player_sprite, item):
# self.player_sprite.bottom = item.top <- Doesn't work for ramps
self.player_sprite.bottom += 0.25
if item.change_x != 0:
self.player_sprite.center_x += item.change_x
# print(f"Spot Y ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
else:
pass
# TODO: The code below can't execute, as "item" doesn't
# exist. In theory, this condition should never be arrived at.
# Collision while player wasn't moving, most likely
# moving platform.
# if self.player_sprite.center_y >= item.center_y:
# self.player_sprite.bottom = item.top
# else:
# self.player_sprite.top = item.bottom
self.player_sprite.change_y = min(0.0, hit_list[0].change_y)
# print(f"Spot B ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
self.player_sprite.center_y = round(self.player_sprite.center_y, 2)
# print(f"Spot Q ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
# --- Move in the x direction
self.player_sprite.center_x += self.player_sprite.change_x
check_again = True
while check_again:
check_again = False
# Check for wall hit
hit_list = check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
change_x = self.player_sprite.change_x
if change_x > 0:
for item in hit_list:
# print(f"Spot 1 ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
# See if we can "run up" a ramp
self.player_sprite.center_y += change_x
if len(
check_for_collision_with_list(
self.player_sprite, self.platforms)) > 0:
self.player_sprite.center_y -= change_x
self.player_sprite.right = min(
item.left, self.player_sprite.right)
# print(f"Spot R ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
check_again = True
break
# else:
# print("Run up ok 1")
# print(f"Spot 2 ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
elif change_x < 0:
for item in hit_list:
# See if we can "run up" a ramp
self.player_sprite.center_y -= change_x
if len(
check_for_collision_with_list(
self.player_sprite, self.platforms)) > 0:
# Can't run up the ramp, reverse
self.player_sprite.center_y += change_x
self.player_sprite.left = max(
item.right, self.player_sprite.left)
# print(f"Reverse 1 {item.right}, {self.player_sprite.left}")
# Ok, if we were shoved back to the right, we need to check this whole thing again.
check_again = True
break
# print(f"Spot 4 ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
else:
print(
"Error, collision while player wasn't moving.\nMake sure you aren't calling multiple updates, like a physics engine update and an all sprites list update."
)
# print(f"Spot E ({self.player_sprite.center_x}, {self.player_sprite.center_y})")
for platform in self.platforms:
if platform.change_x != 0 or platform.change_y != 0:
platform.center_x += platform.change_x
if platform.boundary_left is not None \
and platform.left <= platform.boundary_left:
platform.left = platform.boundary_left
if platform.change_x < 0:
platform.change_x *= -1
if platform.boundary_right is not None \
and platform.right >= platform.boundary_right:
platform.right = platform.boundary_right
if platform.change_x > 0:
platform.change_x *= -1
if check_for_collision(self.player_sprite, platform):
if platform.change_x < 0:
self.player_sprite.right = platform.left
if platform.change_x > 0:
self.player_sprite.left = platform.right
platform.center_y += platform.change_y
if platform.boundary_top is not None \
and platform.top >= platform.boundary_top:
platform.top = platform.boundary_top
if platform.change_y > 0:
platform.change_y *= -1
if platform.boundary_bottom is not None \
and platform.bottom <= platform.boundary_bottom:
platform.bottom = platform.boundary_bottom
if platform.change_y < 0:
platform.change_y *= -1
def update(self, direction=None, player_to_follow=None) -> None:
"""
Move everything and resolve collisions
:return: none
"""
# player and other enemy detection
if isinstance(player_to_follow, arcade.SpriteList):
# checks for player and other entity collisions
hit_list = \
check_for_collision_with_list(self.player,
player_to_follow)
if len(hit_list) > 0:
for item in hit_list:
if self.player.is_attack_state:
if not isinstance(item, Fireball):
item.health -= 1.5
if isinstance(item, Executioner):
item.is_player_hit = True
if isinstance(item, Slime):
item.is_player_hit = True
if isinstance(item, Fireball):
item.is_wall_hit = True
item.is_player_hit = True
if isinstance(item, Boss):
if self.player.is_attack_state:
item.health -= 0.5
# if the player is the user
elif isinstance(self.player, Player):
if self.player.health < 1:
self.player.game_over()
# --- Move sprite
self.player.move_player(direction)
# update x position
self.player.center_x += self.player.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_x > 0:
for item in hit_list:
self.player.right = min(item.left,
self.player.right) - 5
self.player.direction = None
return arcade.key.RIGHT
elif self.player.change_x < 0:
for item in hit_list:
self.player.left = max(item.right,
self.player.left) + 5
self.player.direction = None
return arcade.key.LEFT
# update y position
self.player.center_y += self.player.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_y > 0:
for item in hit_list:
self.player.top = min(item.bottom, self.player.top) - 5
self.player.direction = None
return arcade.key.UP
elif self.player.change_y < 0:
for item in hit_list:
self.player.bottom = max(item.top,
self.player.bottom) + 5
self.player.direction = None
return arcade.key.DOWN
# check for trap hit
hit_list = \
check_for_collision_with_list(self.player, self.traps)
if len(hit_list) > 0:
self.player.health -= 0.1
self.player.change_x, self.player.change_y = 0, 0
# if it isn't the player
elif isinstance(self.player, Slime):
# --- Move sprite
self.player.follow(player_to_follow)
# update x position
self.player.center_x += self.player.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_x > 0:
for item in hit_list:
self.player.right = min(item.left,
self.player.right) - 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
elif self.player.change_x < 0:
for item in hit_list:
self.player.left = max(item.right,
self.player.left) + 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
# update y position
self.player.center_y += self.player.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_y > 0:
for item in hit_list:
self.player.top = min(item.bottom, self.player.top) - 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
elif self.player.change_y < 0:
for item in hit_list:
self.player.bottom = max(item.top,
self.player.bottom) + 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
else:
print("Error, collision while enemy wasn't moving.")
self.player.change_x, self.player.change_y = 0, 0
elif isinstance(self.player, Minion):
# --- Move sprite
self.player.follow(player_to_follow)
if arcade.check_for_collision(self.player, player_to_follow):
self.player.is_player_hit = True
# update x position
self.player.center_x += self.player.change_x
self.player.center_y += self.player.change_y
# Check for wall hit
if self.player.center_x > 890:
self.player.center_x = 890
if self.player.center_x < 20:
self.player.center_x = 20
if self.player.center_y > 890:
self.player.center_y = 890
if self.player.center_y < 20:
self.player.center_y = 20
self.player.change_x, self.player.change_y = 0, 0
elif isinstance(self.player, Executioner):
# --- Move sprite
self.player.follow(player_to_follow)
# update x position
self.player.center_x += self.player.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_x > 0:
for item in hit_list:
self.player.right = min(item.left,
self.player.right) - 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
elif self.player.change_x < 0:
for item in hit_list:
self.player.left = max(item.right,
self.player.left) + 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
else:
print("Error, collision while enemy wasn't moving.")
# update y position
self.player.center_y += self.player.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_y > 0:
for item in hit_list:
self.player.top = min(item.bottom, self.player.top) - 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
elif self.player.change_y < 0:
for item in hit_list:
self.player.bottom = max(item.top,
self.player.bottom) + 5
self.player.direction = None
self.player.movement = not self.player.movement
self.player.hit = True
else:
print("Error, collision while enemy wasn't moving.")
self.player.change_x, self.player.change_y = 0, 0
elif isinstance(self.player, Fireball):
# --- Move sprite
# update x position
self.player.center_x += self.player.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_x > 0:
for item in hit_list:
self.player.right = min(item.left,
self.player.right) - 5
elif self.player.change_x < 0:
for item in hit_list:
self.player.left = max(item.right,
self.player.left) + 5
else:
print("Error, collision while enemy wasn't moving.")
self.player.is_wall_hit = True
self.player.reset = True
# update y position
self.player.center_y += self.player.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player,
self.walls)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player.change_y > 0:
for item in hit_list:
self.player.top = min(item.bottom, self.player.top) - 5
elif self.player.change_y < 0:
for item in hit_list:
self.player.bottom = max(item.top,
self.player.bottom) + 5
else:
print("Error, collision while enemy wasn't moving.")
self.player.is_wall_hit = True
self.player.reset = True
def update(self):
"""
Move everything and resolve collisions.
"""
# --- Add gravity
self.player_sprite.change_y -= self.gravity_constant
# --- Move in the y direction
self.player_sprite.center_y += self.player_sprite.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_y > 0:
for item in hit_list:
self.player_sprite.top = min(item.bottom,
self.player_sprite.top)
elif self.player_sprite.change_y < 0:
for item in hit_list:
while check_for_collision(self.player_sprite, item):
self.player_sprite.bottom += 0.5
if item.change_x != 0:
self.player_sprite.center_x += item.change_x
else:
pass
# TODO: The code below can't execute, as "item" doesn't
# exist. In theory, this condition should never be arrived at.
# Collision while player wasn't moving, most likely
# moving platform.
# if self.player_sprite.center_y >= item.center_y:
# self.player_sprite.bottom = item.top
# else:
# self.player_sprite.top = item.bottom
self.player_sprite.change_y = min(0, hit_list[0].change_y)
# --- Move in the x direction
self.player_sprite.center_x += self.player_sprite.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
change_x = self.player_sprite.change_x
if change_x > 0:
for item in hit_list:
# See if we can "run up" a ramp
self.player_sprite.center_y += change_x
if check_for_collision(self.player_sprite, item):
self.player_sprite.center_y -= change_x
self.player_sprite.right = \
min(item.left, self.player_sprite.right)
elif change_x < 0:
for item in hit_list:
# See if we can "run up" a ramp
self.player_sprite.center_y -= change_x
if check_for_collision(self.player_sprite, item):
self.player_sprite.center_y -= change_x
self.player_sprite.left = max(item.right,
self.player_sprite.left)
else:
print("Error, collision while player wasn't moving.")
for platform in self.platforms:
if platform.change_x != 0 or platform.change_y != 0:
platform.center_x += platform.change_x
if platform.boundary_left is not None \
and platform.left <= platform.boundary_left:
platform.left = platform.boundary_left
if platform.change_x < 0:
platform.change_x *= -1
if platform.boundary_right is not None \
and platform.right >= platform.boundary_right:
platform.right = platform.boundary_right
if platform.change_x > 0:
platform.change_x *= -1
if check_for_collision(self.player_sprite, platform):
if platform.change_x < 0:
self.player_sprite.right = platform.left
if platform.change_x > 0:
self.player_sprite.left = platform.right
platform.center_y += platform.change_y
if platform.boundary_top is not None \
and platform.top >= platform.boundary_top:
platform.top = platform.boundary_top
if platform.change_y > 0:
platform.change_y *= -1
if platform.boundary_bottom is not None \
and platform.bottom <= platform.boundary_bottom:
platform.bottom = platform.boundary_bottom
if platform.change_y < 0:
platform.change_y *= -1
def update(self):
"""
Move everything and resolve collisions.
"""
# --- Add gravity
self.player_sprite.change_y -= self.gravity_constant
# --- Move in the y direction
self.player_sprite.center_y += self.player_sprite.change_y
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
if self.player_sprite.change_y > 0:
for item in hit_list:
self.player_sprite.top = min(item.bottom,
self.player_sprite.top)
elif self.player_sprite.change_y < 0:
for item in hit_list:
while check_for_collision(self.player_sprite, item):
self.player_sprite.bottom += 0.5
if item.change_x != 0:
self.player_sprite.center_x += item.change_x
else:
pass
# TODO: The code below can't execute, as "item" doesn't
# exist. In theory, this condition should never be arrived at.
# Collision while player wasn't moving, most likely
# moving platform.
# if self.player_sprite.center_y >= item.center_y:
# self.player_sprite.bottom = item.top
# else:
# self.player_sprite.top = item.bottom
self.player_sprite.change_y = min(0, hit_list[0].change_y)
# --- Move in the x direction
self.player_sprite.center_x += self.player_sprite.change_x
# Check for wall hit
hit_list = \
check_for_collision_with_list(self.player_sprite,
self.platforms)
# If we hit a wall, move so the edges are at the same point
if len(hit_list) > 0:
change_x = self.player_sprite.change_x
if change_x > 0:
for item in hit_list:
# See if we can "run up" a ramp
self.player_sprite.center_y += change_x
if check_for_collision(self.player_sprite, item):
self.player_sprite.center_y -= change_x
self.player_sprite.right = \
min(item.left, self.player_sprite.right)
elif change_x < 0:
for item in hit_list:
# See if we can "run up" a ramp
self.player_sprite.center_y -= change_x
if check_for_collision(self.player_sprite, item):
self.player_sprite.center_y -= change_x
self.player_sprite.left = max(item.right,
self.player_sprite.left)
else:
print("Error, collision while player wasn't moving.")
for platform in self.platforms:
if platform.change_x != 0 or platform.change_y != 0:
platform.center_x += platform.change_x
if platform.boundary_left is not None \
and platform.left <= platform.boundary_left:
platform.left = platform.boundary_left
if platform.change_x < 0:
platform.change_x *= -1
if platform.boundary_right is not None \
and platform.right >= platform.boundary_right:
platform.right = platform.boundary_right
if platform.change_x > 0:
platform.change_x *= -1
if check_for_collision(self.player_sprite, platform):
if platform.change_x < 0:
self.player_sprite.right = platform.left
if platform.change_x > 0:
self.player_sprite.left = platform.right
platform.center_y += platform.change_y
if platform.boundary_top is not None \
and platform.top >= platform.boundary_top:
platform.top = platform.boundary_top
if platform.change_y > 0:
platform.change_y *= -1
if platform.boundary_bottom is not None \
and platform.bottom <= platform.boundary_bottom:
platform.bottom = platform.boundary_bottom
if platform.change_y < 0:
platform.change_y *= -1
