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How do I use a .jpg or .png as a background picture?

I found a nice image of space that I'd like sitting in the background of this tiny game I'm working on and can't figure out what and where to write it. It needs to be placed behind all classes to make sure that it doesn't block the screen. I thought it might be in class Window, but I'm not sure. I am brand new to python so any help is much appreciated! This is the entire project so far.
import sys, logging, os, random, math, open_color, arcade
#check to make sure we are running the right version of Python
version = (3,7)
assert sys.version_info >= version, "This script requires at least Python {0}.{1}".format(version[0],version[1])
#turn on logging, in case we have to leave ourselves debugging messages
logging.basicConfig(format='[%(filename)s:%(lineno)d] %(message)s', level=logging.DEBUG)
logger = logging.getLogger(__name__)
SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600
MARGIN = 30
SCREEN_TITLE = "Intergalactic slam"
NUM_ENEMIES = 5
STARTING_LOCATION = (400,100)
BULLET_DAMAGE = 10
ENEMY_HP = 10
HIT_SCORE = 10
KILL_SCORE = 100
PLAYER_HP = 100
class Bullet(arcade.Sprite):
def __init__(self, position, velocity, damage):
'''
initializes the bullet
Parameters: position: (x,y) tuple
velocity: (dx, dy) tuple
damage: int (or float)
'''
super().__init__("PNG/laserPink3.png", 0.5)
(self.center_x, self.center_y) = position
(self.dx, self.dy) = velocity
self.damage = damage
def update(self):
'''
Moves the bullet
'''
self.center_x += self.dx
self.center_y += self.dy
class Enemy_Bullet(arcade.Sprite):
def __init__(self, position, velocity, damage):
super().__init__("PNG/laserGreen1.png", 0.5)
(self.center_x, self.center_y) = position
(self.dx, self.dy) = velocity
self.damage = damage
def update(self):
self.center_x += self.dx
self.center_y += self.dy
class Player(arcade.Sprite):
def __init__(self):
super().__init__("PNG/shipYellow_manned.png", 0.5)
(self.center_x, self.center_y) = STARTING_LOCATION
self.hp = PLAYER_HP
class Enemy(arcade.Sprite):
def __init__(self, position):
'''
initializes an alien enemy
Parameter: position: (x,y) tuple
'''
super().__init__("PNG/shipGreen_manned.png", 0.5)
self.hp = ENEMY_HP
(self.center_x, self.center_y) = position
class Window(arcade.Window):
def __init__(self, width, height, title):
super().__init__(width, height, title)
file_path = os.path.dirname(os.path.abspath(__file__))
os.chdir(file_path)
self.set_mouse_visible(True)
arcade.set_background_color(open_color.black)
self.bullet_list = arcade.SpriteList()
self.enemy_list = arcade.SpriteList()
self.enemy_bullet_list = arcade.SpriteList()
self.player = Player()
self.score = 0
self.win = False
self.lose = False
def setup(self):
'''
Set up enemies
'''
for i in range(NUM_ENEMIES):
x = 120 * (i+1) + 40
y = 500
enemy = Enemy((x,y))
self.enemy_list.append(enemy)
def update(self, delta_time):
self.bullet_list.update()
self.enemy_bullet_list.update()
if (not (self.win or self.lose)):
for e in self.enemy_list:
for b in self.bullet_list:
if (abs(b.center_x - e.center_x) <= e.width / 2 and abs(b.center_y - e.center_y) <= e.height / 2):
self.score += HIT_SCORE
e.hp -= b.damage
b.kill()
if (e.hp <= 0):
e.kill()
self.score += KILL_SCORE
if (len(self.enemy_list) == 0):
self.win = True
if (random.randint(1, 75) == 1):
self.enemy_bullet_list.append(Enemy_Bullet((e.center_x, e.center_y - 15), (0, -10), BULLET_DAMAGE))
for b in self.enemy_bullet_list:
if (abs(b.center_x - self.player.center_x) <= self.player.width / 2 and abs(b.center_y - self.player.center_y) <= self.player.height / 2):
self.player.hp -= b.damage
b.kill()
if (self.player.hp <= 0):
self.lose = True
def on_draw(self):
arcade.start_render()
arcade.draw_text(str(self.score), 20, SCREEN_HEIGHT - 40, open_color.white, 16)
arcade.draw_text("HP: {}".format(self.player.hp), 20, 40, open_color.white, 16)
if (self.player.hp > 0):
self.player.draw()
self.bullet_list.draw()
self.enemy_bullet_list.draw()
self.enemy_list.draw()
if (self.lose):
self.draw_game_loss()
elif (self.win):
self.draw_game_won()
def draw_game_loss(self):
arcade.draw_text(str("LOSER!"), SCREEN_WIDTH / 2 - 90, SCREEN_HEIGHT / 2 - 10, open_color.white, 30)
def draw_game_won(self):
arcade.draw_text(str("WINNER!"), SCREEN_WIDTH / 2 - 90, SCREEN_HEIGHT / 2 - 10, open_color.white, 30)
def on_mouse_motion(self, x, y, dx, dy):
'''
The player moves left and right with the mouse
'''
self.player.center_x = x
def on_mouse_press(self, x, y, button, modifiers):
if button == arcade.MOUSE_BUTTON_LEFT:
x = self.player.center_x
y = self.player.center_y + 15
bullet = Bullet((x,y),(0,10),BULLET_DAMAGE)
self.bullet_list.append(bullet)
def main():
window = Window(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
window.setup()
arcade.run()
if __name__ == "__main__":
main()

One way to do it would be to load the .jpg or .png as a texture, and draw that texture each frame, as big as the screen is (or bigger!).
I haven't tested this, but as an example, loading the texture could be done in Window.__init__, like so (reference):
self.background = arcade.load_texture('PNG/background.png')
And then in on_draw, just after you call start_render, you would draw it (reference), passing the required center coordinates, as well as width and height:
self.background.draw(SCREEN_WIDTH/2, SCREEN_HEIGHT/2, SCREEN_WIDTH, SCREEN_HEIGHT)
The reason it needs to be the first thing is because everything is drawn back-to-front, like you would do in a painting.
If the image is not the exact same size as your screen/window, your background will probably be stretched/squished. If that's not what you want, the easiest fix would be to change the image so that it's the right size.

Yes, you should be able to add it to class window...
You could do something like this to add it:
def __init__(self, width, height, title):
super().__init__(width, height, title)
file_path = os.path.dirname(os.path.abspath(__file__))
os.chdir(file_path)
self.set_mouse_visible(True)
arcade.set_background_color(open_color.black)
self.bullet_list = arcade.SpriteList()
self.enemy_list = arcade.SpriteList()
self.enemy_bullet_list = arcade.SpriteList()
self.player = Player()
self.score = 0
self.win = False
self.lose = False
self.background = None
def setup(self):
'''
Set up enemies
'''
self.background = arcade.load_texture("images/background.jpg")
for i in range(NUM_ENEMIES):
x = 120 * (i+1) + 40
y = 500
enemy = Enemy((x,y))
self.enemy_list.append(enemy)

Pygame, Collision between 2 objects in the same group

So, i am trying to create a game where aliens spawn from 3 specific places. Each Alien will spawn randomly in one of the 3. But there will always be at least one alien, that will spawn on top of another one. I want to delete that alien and spawn him randomly in another spawn point. If it is empty he will stay if not the process will be repeated. The thing is that i cannot find a way to detect collision of 2 objects that are in the same group.
I just started learning pygame so 1) My question may be stupid 2) My way of spawning probably is very inefficient
Here is the Alien class:
class Alien(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((80,60))
self.image.fill(GREY)
self.rect = self.image.get_rect()
spawn_point1 = x1,y1 = -30, 70
spawn_point2 = x2,y2 = -30, 150
spawn_point3 = x3,y3 = -30, 230
random_spawn = random.choice([spawn_point1,spawn_point2,spawn_point3])
self.rect.center = random_spawn
self.speedx = 10
def update(self):
spawn_point1 = x1,y1 = -30, 70
spawn_point2 = x2,y2 = -30, 150
spawn_point3 = x3,y3 = -30, 230
self.speedx = 10
random_spawn = random.choice([spawn_point1,spawn_point2,spawn_point3])
self.rect.x += self.speedx
if self.rect.x > WIDTH + 20:
self.rect.center = random_spawn
And here is the part where i detect collision(This part doesnt work)
aliens_col = pygame.sprite.groupcollide(aliens, aliens, True, False)
for i in aliens_col:
alien = Alien()
aliens.add(alien)
all_sprites.add(aliens)

Here is an implementation of the Bounding Box test.
import random
class Rectangle:
def __init__(self, height, width, x, y):
self.height = height
self.width = width
self.x = x
self.y = y
def collided_with_another_rectangle(self, rect):
""" Assumes rectangles are same size or that this rectangle is smaller than the other rectangle"""
if self.x > (rect.x + rect.width):
# Is to the right of the other rectangle
return False
elif (self.x + self.width) < rect.x:
# is to the left of the other rectangle
return False
elif (self.y + self.height) < rect.y:
# is above the other rectangle
return False
elif self.y > (rect.y + rect.height):
# is below the other rectangle
return False
else:
return True
collision_count = 0
for i in range(0, 1000):
# Here I pick random locations on a 1000X1000 screen for the first rectangle
x1 = random.randint(0, 1000)
y1 = random.randint(0, 1000)
# Here I pick random locations on a 1000X1000 screen for the second rectangle
rect1 = Rectangle(100, 100, x1, y1)
x2 = random.randint(0, 1000)
y2 = random.randint(0, 1000)
rect2 = Rectangle(100, 100, x2, y2)
"""
I use the collided with another rectangle function to test if the first rectangle is above,below,
to the right or to the left of the other rectangle. If neither of these are true then the rectangles
have collided.
"""
if rect1.collided_with_another_rectangle(rect2):
collision_count += 1
print("Rect1 X and Y:" + str(x1) + " " + str(y1))
print("Rect2 X and Y:" + str(x2) + " " + str(y2))
print("collided")
print("Collision Count:" + str(collision_count))

I'm still not absolutely sure what you want to achieve, but I think this example will be helpful to you.
When a sprite leaves the screen, I call the reset_pos method in which I iterate over the three spawn points to set the position to one spawn after the other and then I use another for loop to iterate over the sprites to check if one collides.
If a sprite collides, I continue with the next spawn point.
If no sprite collides, I just return from the method.
If no spawn is free, I remove the sprite (but you can do something else).
import random
import pygame
from pygame.math import Vector2
pygame.init()
WIDTH, HEIGHT = 640, 480
class Alien(pygame.sprite.Sprite):
def __init__(self, aliens):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface((80, 60))
self.image.fill((120, random.randrange(255), random.randrange(255)))
self.rect = self.image.get_rect()
self.spawn_points = [(-30, 70), (-30, 150), (-30, 230)]
self.aliens = aliens
self.reset_pos()
self.speedx = 10
def update(self):
self.rect.x += self.speedx
if self.rect.x > WIDTH + 20:
self.reset_pos()
def reset_pos(self):
random.shuffle(self.spawn_points) # Shuffle the spawns.
for spawn in self.spawn_points:
# Set the position to one of the spawns.
self.rect.center = spawn
# Check if this sprite collides with another one.
for sprite in self.aliens:
if sprite is self: # Skip self.
continue
if self.rect.colliderect(sprite.rect):
break # Break out of the loop if the spawn is occupied.
else: # The else means no 'break' occurred in the for loop above,
# so the spawn must be free.
return # Break out of the method if the spawn is free.
# I just remove the sprite if no spawn is free. You can do something else here.
self.kill()
def main():
screen = pygame.display.set_mode((640, 480))
clock = pygame.time.Clock()
aliens = pygame.sprite.Group()
for _ in range(3):
# I pass the aliens group to the sprite because we need to
# iterate over it to see if a sprite collides.
alien = Alien(aliens)
aliens.add(alien)
all_sprites = pygame.sprite.Group(aliens)
done = False
while not done:
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
elif event.type == pygame.MOUSEBUTTONDOWN:
al = Alien(aliens)
all_sprites.add(al)
aliens.add(al)
all_sprites.update()
screen.fill((30, 30, 30))
all_sprites.draw(screen)
pygame.display.flip()
clock.tick(30)
if __name__ == '__main__':
main()
pygame.quit()

When using the same group in both of the group-paramaters of groupcollide it will always consider the sprite it is checking in group_a as colliding with that same sprite in group_b. This results in groupcollide always returning a collision.
To get around this I created a new function in pygame's sprite.py that ignores single collisions and only returns collisions >= 2. My only change was to add:
if len(collision) >=2:
And then the required tab for the following line(s).
The code I added to sprite.py is pasted below but the tab for the def intra_groupcollide is one too far:
def intra_groupcollide(groupa, groupb, dokilla, dokillb, collided=None):
"""detect collision between a group and itself.
This is modified from groupcollide but excludes collisions <=1
pygame.sprite.groupcollide(groupa, groupb, dokilla, dokillb):
return dict
"""
crashed = {}
# pull the collision function in as a local variable outside
# the loop as this makes the loop run faster
sprite_collide_func = spritecollide
if dokilla:
for group_a_sprite in groupa.sprites():
collision = sprite_collide_func(group_a_sprite, groupb,
dokillb, collided)
if collision:
if len(collision) >=2:
crashed[group_a_sprite] = collision
group_a_sprite.kill()
else:
for group_a_sprite in groupa:
collision = sprite_collide_func(group_a_sprite, groupb,
dokillb, collided)
if collision:
if len(collision) >=2:
crashed[group_a_sprite] = collision
#print(crashed)
return crashed
Then in my own python program, I simply replaced groupcollide with intra_groupcollide. I set both kill paramaters as 'false' because in my usage I'm bouncing them off each other. I have not tested this code with them set to 'true'.
I found sprite.py in my file system by following this answer:
Where are the python modules stored?

Sprite not moving in the same direction it is facing

I have an issue with my sprite not moving in the same direction as it is facing. It is top view of a beetle, 10 images animating its leg movements. The sprite animation works fine, choosing new 'random' direction by rotating the image and re-centering to previous center is working too.
What I can't get to work is the sprite to move 'forward', that is to move in the new direction it chooses/faces every second or so. The new direction is simply a small 10-15 degrees rotation left or right from previous position. Instead it moves in what seem like random movements every time the sprite chooses a new direction. For example it will move southwest while facing east, or move north while facing south etc.
I suspect the problem is in the move() method where the movement isn't properly translated via trig values. I am adding to the rect.x values because it is the same as the cartesian coords system while subtracting from rect.y values because it is inverted in pygame compared to cartesian. Going down is increasing positively, up - decreasing y values, increasing negatively.
The class for the beetle sprite is below:
class Foe():
def __init__(self, location):
self.sprites = []
for i in range(1, 11):
file = pg.image.load("beetleprac1/000"+str(i)+"a.png").convert() # 10 sprite files named "0001a-10a.png" last 1 is idle stance
#file.set_colorkey((0, 255, 255))
self.sprites.append(file)
self.move_anim_index = 9
self.image = self.sprites[self.move_anim_index]
self.rotated_image = self.image.copy()
self.rect = self.image.get_rect(center=location)
self.move_rect_coords = [self.rect.x, self.rect.y]
self.angle = 90
self.speed = 3
self.time = 0
self.frames_counter = 0
def move_anim(self, rate=2): # rate is in frames
if self.frames_counter % rate == 0:
self.move_anim_index += 1
if self.move_anim_index >= 9:
self.move_anim_index = 0
self.image = self.sprites[self.move_anim_index]
#self.rect = self.image.get_rect(center=self.rect.center)
self.rotated_image = self.image.copy()
self.rotated_image = pg.transform.rotate(self.image, self.angle - 90)
self.rect = self.rotated_image.get_rect(center=self.rect.center)
def move(self, last_tick):
self.move_anim()
self.rect.x += int(self.speed * math.cos(self.angle))
self.rect.y -= int(self.speed * math.sin(self.angle))
self.move_rect_coords = [self.rect.x, self.rect.y]
def change_direction(self, change_time): # change_time in frames
if self.frames_counter % change_time == 0:
a = random.choice([-1, 1])
self.angle += 15
if self.angle < 0: self.angle += 360
if self.angle > 360: self.angle -=360
#if self.rect.x <
def track_time(self, last_tick, amount):
self.time += last_tick
self.frames_counter += 1
if self.time >= last_tick * amount:
self.time = 0
self.counter = 0
def think(self, last_tick):
self.track_time(last_tick, FPS*2)
self.change_direction(FPS)
def update(self, last_tick, screen_rect):
self.think(last_tick)
self.move(last_tick)
def draw(self, screen):
screen.blit(self.rotated_image, self.move_rect_coords)
And here is the full code and repository at github: https://github.com/fn88/buganimprac2

sin(), cos() and other trigonometric functions use radians -> cos(math.radians(angle))

pygame bullet physics messed up by scrolling

the code below is the bullet class for my shooter game in pygame. as you can see if you run the full game (https://github.com/hailfire006/economy_game/blob/master/shooter_game.py) the code works great to fire bullets at the cursor as long as the player isn't moving. However, I recently added scrolling, where I change a global offsetx and offsety every time the player gets close to an edge. These offsets are then used to draw each object in their respective draw functions.
unfortunately, my bullet physics in the bullet's init function no longer work as soon as the player scrolls and the offsets are added. Why are the offsets messing up my math and how can I change the code to get the bullets to fire in the right direction?
class Bullet:
def __init__(self,mouse,player):
self.exists = True
centerx = (player.x + player.width/2)
centery = (player.y + player.height/2)
self.x = centerx
self.y = centery
self.launch_point = (self.x,self.y)
self.width = 20
self.height = 20
self.name = "bullet"
self.speed = 5
self.rect = None
self.mouse = mouse
self.dx,self.dy = self.mouse
distance = [self.dx - self.x, self.dy - self.y]
norm = math.sqrt(distance[0] ** 2 + distance[1] ** 2)
direction = [distance[0] / norm, distance[1] / norm]
self.bullet_vector = [direction[0] * self.speed, direction[1] * self.speed]
def move(self):
self.x += self.bullet_vector[0]
self.y += self.bullet_vector[1]
def draw(self):
make_bullet_trail(self,self.launch_point)
self.rect = pygame.Rect((self.x + offsetx,self.y + offsety),(self.width,self.height))
pygame.draw.rect(screen,(255,0,40),self.rect)

You don't take the offset into account when calculating the angle between the player and the mouse. You can fix this by changing the distance like this:
distance = [self.dx - self.x - offsetx, self.dy - self.y - offsety]

Why pygame.draw.circle doesn't work in this code?

I have a ball object that waits one second in the middle of the screen before moving. This is the update method:
def update(self, dt):
now = pygame.time.get_ticks() / 1000
if now - self._spawn_time >= BALL_WAIT_TIME:
self.rect = self.calcnewpos(dt)
self.handle_collision()
else:
step = 255 / FPS
value = int(self._frame * step)
rgb = (value, value, value)
self._draw_ball(rgb)
self._frame += 1
That one second happens below the else clause. My goal is to have the ball image go from black (8, 8, 8) to white (255, 255, 255) in that time but as it is _draw_ball doesn't do anything.
def _draw_ball(self, rgb):
pygame.draw.circle(self.image, rgb, self.rect.center, BALL_RADIUS)
The funny things is, it works the first time when it's called in __init__. I've tried taking lines out of update and testing this code on its own in another module but can't figure out what's the problem. Why is pygame.draw.circle not drawing the the circles in the colors passed by the update method?
Here is the whole class:
#!python3
class Ball(pygame.sprite.Sprite):
def __init__(self, game, velocity):
super(Ball, self).__init__()
self.image = pygame.Surface((BALL_RADIUS*2, BALL_RADIUS*2))
self.image.fill(BLACK)
self.image.set_colorkey(BLACK, RLEACCEL)
self.rect = self.image.get_rect()
screen = pygame.display.get_surface()
self.area = screen.get_rect().inflate(-GAP*2, 0)
self.velocity = velocity
self.game = game
self.start_to_the = random.choice(['left', 'right'])
self._draw_ball(BALL_COLOR)
self.reinit()
def _draw_ball(self, rgb):
pygame.draw.circle(self.image, rgb, self.rect.center, BALL_RADIUS)
def _hit_topbottom(self):
return self.rect.top < self.area.top or self.rect.bottom > self.area.bottom
def _hit_leftright(self):
if self.rect.left < self.area.left: return 'left'
elif self.rect.right > self.area.right: return 'right'
else: return 0
def reinit(self):
self._spawn_time = pygame.time.get_ticks() / 1000
self._frame = 1
if self.start_to_the == 'left':
self.velocity = Vec2D(-BALL_SPEED, 0)
else:
self.velocity = Vec2D(BALL_SPEED, 0)
self.rect.center = self.area.center
def update(self, dt):
now = pygame.time.get_ticks() / 1000
if now - self._spawn_time >= BALL_WAIT_TIME:
self.rect = self.calcnewpos(dt)
self.handle_collision()
else:
step = 255 / FPS
value = int(self._frame * step)
rgb = (value, value, value)
self.image.fill(rgb)
self._frame += 1
def calcnewpos(self, dt):
(dx, dy) = self.velocity.x, self.velocity.y
return self.rect.move(dx, dy)
def handle_collision(self):
(dx, dy) = self.velocity.x, self.velocity.y
if self._hit_topbottom():
dy = -dy
elif self._hit_leftright():
side = self._hit_leftright()
self.game.enemy.update_hitpos()
self.game.increase_score(side)
if side == 'left': self.start_to_the = 'right'
elif side == 'right': self.start_to_the = 'left'
self.reinit()
return
else:
if self.hit_paddle():
paddle = self.hit_paddle()
paddle.handle_collision()
if paddle == self.game.paddles['left']:
self.rect.left = GAP + PADDLE_WIDTH
elif paddle == self.game.paddles['right']:
self.rect.right = SCREEN_WIDTH - (GAP + PADDLE_WIDTH)
dx = -dx
dy = (self.rect.centery - paddle.rect.centery)
dy = (math.copysign(min(abs(dy) // 16 * 16, 32), dy)) / 4
paddle.handle_collision()
self.velocity = Vec2D(dx, dy)
def hit_paddle(self):
paddles = self.game.paddles.values()
for paddle in paddles:
if self.rect.colliderect(paddle.rect): return paddle

I don't see any calls to pygame.display.flip. This is the function responsible for updating the screen with the current state of your display surface. It also doesn't look like you are redrawing your ball on the display surface. Somewhere, probably in update or _draw_ball there should be calls like the following:
self.screen.draw(self.image, self.rect)
pygame.display.flip()
The first line draws the image of the ball to the surface representing the screen, and the second call updates the screen to reflect the new surface.
My second theory is that you are drawing new frames of the ball outside of the bounds of self.image. This theory comes from seeing that are moving the ball's rect according to velocity, but always drawing a circle on self.image at self.rect's center. The size of self.image is only BALL_RADIUS*2, which makes it easy to draw outside of it if self.rect's topleft becomes something that's not (0,0). Even if this isn't your problem now, it will be later.

in pygame the draw circle statement is :
pygame.draw.circle (SURFACE, COLOUR, (X, Y), SIZE, 0)
if you put your screen.fill statement after the circle statement then it will draw the circle and immediately cover it up with the colour of the screen, making your circle disappear a 10000th of a second after its drawn.