Asteroids.py

# implementation of Asteroids
import simplegui
import math
import random

# globals for user interface
WIDTH = 800
HEIGHT = 600
score = 0
num_col = 0
num_col_col = 0
lives = 3
time = 0.5
started = False
MAX_ROCKS = 12
OFFSET = 100**2 # rocks won't spawn closer to ship than sqrt(OFFSET)
diff = 0

class ImageInfo:
    def __init__(self, center, size, radius = 0, lifespan = None, animated = False):
        self.center = center
        self.size = size
        self.radius = radius
        if lifespan:
            self.lifespan = lifespan
        else:
            self.lifespan = float('inf')
        self.animated = animated

    def get_center(self):
        return self.center

    def get_size(self):
        return self.size

    def get_radius(self):
        return self.radius

    def get_lifespan(self):
        return self.lifespan

    def get_animated(self):
        return self.animated

    
# art assets created by Kim Lathrop, may be freely re-used in non-commercial projects, please credit Kim
    
# debris images - debris1_brown.png, debris2_brown.png, debris3_brown.png, debris4_brown.png
#                 debris1_blue.png, debris2_blue.png, debris3_blue.png, debris4_blue.png, debris_blend.png
debris_info = ImageInfo([320, 240], [640, 480])
debris_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/debris2_blue.png")

# nebula images - nebula_brown.png, nebula_blue.png
nebula_info = ImageInfo([400, 300], [800, 600])
nebula_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/nebula_blue.png")

# splash image
splash_info = ImageInfo([200, 150], [400, 300])
splash_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/splash.png")

# ship image
ship_info = ImageInfo([45, 45], [90, 90], 35)
ship_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/double_ship.png")

# missile image - shot1.png, shot2.png, shot3.png
missile_info = ImageInfo([5,5], [10, 10], 3, 50)
missile_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/shot2.png")

# asteroid images - asteroid_blue.png, asteroid_brown.png, asteroid_blend.png
asteroid_info = ImageInfo([45, 45], [90, 90], 40)
asteroid_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/asteroid_blue.png")

# animated explosion - explosion_orange.png, explosion_blue.png, explosion_blue2.png, explosion_alpha.png
explosion_info = ImageInfo([64, 64], [128, 128], 17, 24, True)
explosion_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/lathrop/explosion_alpha.png")

# load 81 frame sprite sheer for explosion - image generated by phaedy explosion generator, source is hasgraphics.com
ship_explosion_info = ImageInfo([50, 50], [100, 100], 17, 81, True)
ship_explosion_image = simplegui.load_image("http://commondatastorage.googleapis.com/codeskulptor-assets/explosion.hasgraphics.png")

# sound assets purchased from sounddogs.com, please do not redistribute
# .ogg versions of sounds are also available, just replace .mp3 by .ogg
soundtrack = simplegui.load_sound("http://commondatastorage.googleapis.com/codeskulptor-assets/sounddogs/soundtrack.mp3")
missile_sound = simplegui.load_sound("http://commondatastorage.googleapis.com/codeskulptor-assets/sounddogs/missile.mp3")
missile_sound.set_volume(.5)
ship_thrust_sound = simplegui.load_sound("http://commondatastorage.googleapis.com/codeskulptor-assets/sounddogs/thrust.mp3")
explosion_sound = simplegui.load_sound("http://commondatastorage.googleapis.com/codeskulptor-assets/sounddogs/explosion.mp3")

# helper functions to handle transformations
def angle_to_vector(ang):
    return [math.cos(ang), math.sin(ang)]

def dist(p, q):
    return math.sqrt((p[0] - q[0]) ** 2 + (p[1] - q[1]) ** 2)

def process_sprite_group(spriteSet,canvas):
    for sprite in set(spriteSet):
        if sprite.remove:
            spriteSet.remove(sprite)
        sprite.update()
        sprite.draw(canvas)

def group_collide(group, other_object):
    global num_col, explosion_group, ship_explosion_group
    for rock in set(group):
        if rock.collide(other_object, 0):
            if other_object.get_type()!='ship':
                explosion_group.add(Sprite(other_object.get_position(), other_object.get_velocity(), other_object.get_angle(), 0, explosion_image, explosion_info, explosion_sound))
            else:
                ship_explosion_group.add(Ship(other_object.get_position(), other_object.get_velocity(), other_object.get_angle(), explosion_image, explosion_info, explosion_sound))
            group.remove(rock)
            num_col += 1
            return True
    return False

def group_group_collide(rocks, rockets):
    global num_col, num_col_col
    for rocket in list(rockets):
        if group_collide(rocks, rocket):
            rockets.remove(rocket)
            num_col -= 1
            num_col_col += 1

# Ship class
class Ship:

    def __init__(self, pos, vel, angle, image, info, sound=None):
        self.pos = [pos[0], pos[1]]
        self.vel = [vel[0], vel[1]]
        self.thrust = False
        self.angle = angle
        self.angle_vel = 0
        self.image = image
        self.image_center = info.get_center()
        self.image_size = info.get_size()
        self.radius = info.get_radius()
        self.animated = info.get_animated()
        self.lifespan = ship_explosion_info.get_lifespan()
        self.remove = False
        self.age = -1 # to offset weird tile indexing
        if sound:
            sound.rewind()
            sound.play()
        
    def draw(self,canvas):
        if self.animated:
            exp_dim = ship_explosion_info.get_lifespan()/9
            explosion_index = [self.age % exp_dim, (self.age // exp_dim) % exp_dim]
            canvas.draw_image(ship_explosion_image,
                              [ship_explosion_info.get_center()[0] + explosion_index[0] * ship_explosion_info.get_size()[0], 
                               ship_explosion_info.get_center()[1] + explosion_index[1] * ship_explosion_info.get_size()[1]], 
                               ship_explosion_info.get_size(), self.pos, self.image_size, self.angle)
        elif self.thrust:
            canvas.draw_image(self.image, [self.image_center[0] + self.image_size[0], self.image_center[1]] , self.image_size,
                              self.pos, self.image_size, self.angle)
        else:
            canvas.draw_image(self.image, self.image_center, self.image_size,
                              self.pos, self.image_size, self.angle)

    def update(self):
        # update angle
        self.angle += self.angle_vel
        self.age += 1
        if self.age>=self.lifespan-2: # to offset weird tile indexing
            self.remove = True # remove explosion
        
        # update position
        self.pos[0] = (self.pos[0] + self.vel[0]) % WIDTH
        self.pos[1] = (self.pos[1] + self.vel[1]) % HEIGHT

        # update velocity
        if self.thrust:
            acc = angle_to_vector(self.angle)
            self.vel[0] += acc[0] * .1
            self.vel[1] += acc[1] * .1
            
        self.vel[0] *= .99
        self.vel[1] *= .99

    def set_thrust(self, on):
        self.thrust = on
        if on:
            ship_thrust_sound.rewind()
            ship_thrust_sound.play()
        else:
            ship_thrust_sound.pause()
       
    def increment_angle_vel(self):
        self.angle_vel += .05
        
    def decrement_angle_vel(self):
        self.angle_vel -= .05
        
    def shoot(self):
        global missile_group
        forward = angle_to_vector(self.angle)
        missile_pos = [self.pos[0] + self.radius * forward[0], self.pos[1] + self.radius * forward[1]]
        missile_vel = [self.vel[0] + 6 * forward[0], self.vel[1] + 6 * forward[1]]
        missile_group.add(Sprite(missile_pos, missile_vel, self.angle, 0, missile_image, missile_info, missile_sound))
    
    def get_position(self):
        return self.pos
    
    def get_radius(self):
        return self.radius
    
    def get_velocity(self):
        return self.vel
    
    def get_angle(self):
        return self.angle
    
    def get_type(self):
        return 'ship'
    
# Sprite class
class Sprite:
    def __init__(self, pos, vel, ang, ang_vel, image, info, sound = None):
        self.pos = [pos[0],pos[1]]
        self.vel = [vel[0],vel[1]]
        self.angle = ang
        self.angle_vel = ang_vel
        self.image = image
        self.image_center = info.get_center()
        self.image_size = info.get_size()
        self.radius = info.get_radius()
        self.lifespan = info.get_lifespan()
        self.animated = info.get_animated()
        self.age = 0
        self.remove = False
        if sound:
            sound.rewind()
            sound.play()
   
    def draw(self, canvas):
        if self.animated:
            current_exp_index = (self.age % explosion_info.get_lifespan()) // 1
            current_exp_center = [explosion_info.get_center()[0] + current_exp_index * explosion_info.get_size()[0], explosion_info.get_center()[1]]
            canvas.draw_image(explosion_image, current_exp_center, self.image_size,
                          self.pos, self.image_size, self.angle)
        else:
            canvas.draw_image(self.image, self.image_center, self.image_size,
                          self.pos, self.image_size, self.angle)

    def update(self):
        # update angle
        self.angle += self.angle_vel
        self.age += 1
        if self.age>=self.lifespan:
            self.remove = True # remove explosion
        
        
        # update position
        self.pos[0] = (self.pos[0] + self.vel[0]) % WIDTH
        self.pos[1] = (self.pos[1] + self.vel[1]) % HEIGHT

    def get_position(self):
        return self.pos

    def get_radius(self):
        return self.radius
    
    def get_velocity(self):
        return self.vel
    
    def get_angle(self):
        return self.angle
    
    def collide(self, other, offset):
        [x1,y1] = self.get_position()
        r1 = self.get_radius()
        [x2,y2] = other.get_position()
        r2 = other.get_radius()
        if (x2-x1)**2+(y2-y1)**2-(r1+r2)**2>offset:
            return False
        else:
            return True
    
    def get_type(self):
        return 'sprite'
        
# key handlers to control ship   
def keydown(key):
    if key == simplegui.KEY_MAP['left']:
        my_ship.decrement_angle_vel()
    elif key == simplegui.KEY_MAP['right']:
        my_ship.increment_angle_vel()
    elif key == simplegui.KEY_MAP['up']:
        my_ship.set_thrust(True)
    elif key == simplegui.KEY_MAP['space']:
        my_ship.shoot()
        
def keyup(key):
    if key == simplegui.KEY_MAP['left']:
        my_ship.increment_angle_vel()
    elif key == simplegui.KEY_MAP['right']:
        my_ship.decrement_angle_vel()
    elif key == simplegui.KEY_MAP['up']:
        my_ship.set_thrust(False)
        
# mouseclick handlers that reset UI and conditions whether splash image is drawn
def click(pos):
    global started, num_col, num_col_col, diff
    center = [WIDTH / 2, HEIGHT / 2]
    size = splash_info.get_size()
    inwidth = (center[0] - size[0] / 2) < pos[0] < (center[0] + size[0] / 2)
    inheight = (center[1] - size[1] / 2) < pos[1] < (center[1] + size[1] / 2)
    if (not started) and inwidth and inheight:
        started = True
        num_col=0
        num_col_col=0
        diff=0
        soundtrack.play()

def draw(canvas):
    global time, started, rock_group
    
    # animiate background
    time += 1
    center = debris_info.get_center()
    size = debris_info.get_size()
    wtime = (time / 8) % center[0]
    canvas.draw_image(nebula_image, nebula_info.get_center(), nebula_info.get_size(), [WIDTH / 2, HEIGHT / 2], [WIDTH, HEIGHT])
    canvas.draw_image(debris_image, [center[0] - wtime, center[1]], [size[0] - 2 * wtime, size[1]], 
                                [WIDTH / 2 + 1.25 * wtime, HEIGHT / 2], [WIDTH - 2.5 * wtime, HEIGHT])
    canvas.draw_image(debris_image, [size[0] - wtime, center[1]], [2 * wtime, size[1]], 
                                [1.25 * wtime, HEIGHT / 2], [2.5 * wtime, HEIGHT])

    # draw UI
    canvas.draw_text("Lives", [50, 50], 22, "White")
    canvas.draw_text("Difficulty", [360, 50], 22, "White")
    canvas.draw_text("Score", [680, 50], 22, "White")
    canvas.draw_text(str(lives-num_col), [50, 80], 22, "White")
    canvas.draw_text(str(diff), [360, 80], 22, "White")
    canvas.draw_text(str(score+num_col_col), [680, 80], 22, "White")

    # draw and update ship
    my_ship.draw(canvas)
    my_ship.update()

    process_sprite_group(rock_group, canvas)
    process_sprite_group(missile_group, canvas)
    process_sprite_group(explosion_group, canvas)
    process_sprite_group(ship_explosion_group, canvas)
    group_collide(rock_group, my_ship)
    # detect missile/rock collisions
    group_group_collide(missile_group, rock_group)
    
    if lives-num_col<=0:
        started=False
        rock_group=set()
    
    # draw splash screen if not started
    if not started:
        soundtrack.rewind()
        canvas.draw_image(splash_image, splash_info.get_center(), 
                          splash_info.get_size(), [WIDTH / 2, HEIGHT / 2], 
                          splash_info.get_size())

# timer handler that spawns a rock    
def rock_spawner():
    global rock_group, MAX_ROCKS, started, diff
    rock_pos = [random.randrange(0, WIDTH), random.randrange(0, HEIGHT)]
    diff = math.ceil(num_col_col/5) 
    rock_vel = [diff*(random.random() * .6 - .3), diff*(random.random() * .6 - .3)]
    rock_avel = random.random() * .2 - .1
    if len(rock_group)<MAX_ROCKS and started:
        new_rock=Sprite(rock_pos, rock_vel, 0, rock_avel, asteroid_image, asteroid_info)
        if not new_rock.collide(my_ship, OFFSET):
            rock_group.add(new_rock)
            
# initialize stuff
frame = simplegui.create_frame("Asteroids", WIDTH, HEIGHT)

# initialize ship and two sprites
my_ship = Ship([WIDTH / 2, HEIGHT / 2], [0, 0], 0, ship_image, ship_info)
rock_group = set()
missile_group = set()
explosion_group = set()
ship_explosion_group = set()

# register handlers
frame.set_keyup_handler(keyup)
frame.set_keydown_handler(keydown)
frame.set_mouseclick_handler(click)
frame.set_draw_handler(draw)

timer = simplegui.create_timer(1000.0, rock_spawner)

# get things rolling
timer.start()
frame.start()