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How to make fighting game command inputs in PyGame

I am currently making a fighting game and was wondering how command inputs could be added. I understand it is kind of irrelevant and many substitutes are possible, but it would be nice to use familiar fighting game inputs.
I currently have something like this:
keys = pygame.key.get_pressed()
if keys[pygame.K_DOWN]:
commandcount +=1
if commandcount > 0 and commandcount < 30 and keys[pygame.K_RIGHT] and keys[pygame.K_z]:
player1.projectile = True
The "commandcount" helps keep the window of action available until a certain amount of time.
The main problem with this is that you could still press the inputs in whatever order and the projectile would still come out.
Thanks

Try using the pygame.KEYDOWN events instead of pygame.key.get_pressed() so the order can be observed. Use a list to keep track of the order of these KEYDOWN events. When the order matches a specific combo then execute the move and reset the list. The list also gets reset after a certain amount of time with a combo. I made an example program with the combo down, right, z activating a fireball.
import pygame
# pygame setup
pygame.init()
# Open a window on the screen
width, height = 600, 600
screen = pygame.display.set_mode((width, height))
def main():
clock = pygame.time.Clock()
black = (0, 0, 0)
move_combo = []
frames_without_combo = 0
while True:
clock.tick(30) # number of loops per second
frames_without_combo += 1
if frames_without_combo > 30 or len(move_combo) > 2:
print("COMBO RESET")
frames_without_combo = 0
move_combo = []
screen.fill(black)
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
quit()
if event.type == pygame.KEYDOWN:
move_combo.append(event.key) # Only keys for combos should be added
if move_combo == [pygame.K_DOWN, pygame.K_RIGHT, pygame.K_z]:
print("FIRE BALL")
frames_without_combo = 0
print(move_combo)
pygame.display.update()
main()

"pygame.error: display Surface quit" when running the code

I am trying to make a simple moving game with Pygame since I am currently learning it. Whenever i try to run the code I keep on getting a problem saying: "pygame.error: display Surface quit"
I've tried adding "break" at the end but the window closes immediately! I've tried searching for the solution but I can't find one that helps my code.
import pygame
import random
pygame.init()
# Window setup
size = [400, 400]
screen = pygame.display.set_mode(size)
clock = pygame.time.Clock()
# player position
x = size[0] // 2
y = size[1] // 2
# ball position
ballX = random.randrange(0, size[0])
ballY = random.randrange(0, size[1])
# colours
red = pygame.color.Color('#FF8080')
blue = pygame.color.Color('#8080FF')
white = pygame.color.Color('#FFFFFF')
black = pygame.color.Color('#000000')
def CheckOffScreenX(x):
if x > size[0]:
x = 0
elif x < 0:
x = size[0]
return x
def CheckOffScreenY(y):
if y > size[1]:
y = 0
elif y < 0:
y = size[1]
return y
# Game loop
done = False
while not done:
screen.fill(black)
keys = pygame.key.get_pressed()
#player movement
if keys[pygame.K_w]:
y -=1
if keys[pygame.K_s]:
y +=1
if keys[pygame.K_a]:
x -=1
if keys[pygame.K_d]:
x +=1
# Check offscreen
x = CheckOffScreenX(x)
y = CheckOffScreenY(y)
# draw player
pygame.draw.circle(screen, red, [x, y], 6)
pygame.display.flip()
# draw ball
pygame.draw.circle(screen, blue, [ballX, ballY], 6)
pygame.display.flip()
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
clock.tick(32)
pygame.quit()
Any help would be appreciated!

The issue is the pygame.quit() insider the main loop. pygame.quit() uninitialize all pygame modules. After the modules are uninitialized all further calls to pygyme instructions (in the next frame) will cause a crash.
Do pygame.quit() after the main loop, when the application has end.
done = False
while not done:
screen.fill(black)
# [...]
# pygame.quit() <----- delete
pygame.quit() # <---- add
Note, probably you've added an Indentation when you copied the code.

Why doesn't my tank move when I press "a" and "d"?

Currently, I am stuck on trying to get my tank to move when the user presses "a" and "d". The lines involving pressing a key to move the tank seem correct and I believe should work. This is also my first time using one of these forums. Please provide feedback so I can improve. Thank you for your help.
I have asked my teacher and friends for help, but they are all wondering why the tank will not move. I also have searched over the internet and youtube for answers. A weird thing is that my friend and I directly copied a youtube video on user movement where the user can move a rectangle around. My friend can hold down "w","a","s",or "d" to move the rectangle, but I can not hold down "w","a","s",or "d" to move it but need to spam the button. What is weird is that when you move your mouse around, I can then hold down "w","a","s",or "d".
import pygame
from pygame.locals import *
import math
import random
width = 640
height = 480
screen = pygame.display.set_mode((width, height))
pygame.display.set_caption("2 Player Tanks")
def gameloop():
pygame.init()
time = pygame.time.get_ticks()
screen.fill(white)
tankx = 100
tanky = 100
tankwidth = 40
tankheight = 20
turretwidth = 5
wheelwidth = 5
tankmove = 5
def tank(x,y):
x = int(x)
y = int(y)
pygame.draw.circle(screen,black,(x,y),10)
pygame.draw.rect(screen,black,(x-tankheight,y,tankwidth,tankheight))
pygame.draw.line(screen,black,(x,y),(x-20,y-20), turretwidth)
startx = 15
for i in range(7):
pygame.draw.circle(screen,black,(x-startx,y+20),wheelwidth)
startx -= 5
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
keys= pygame.key.get_pressed()
if keys[pygame.K_a]:
tankx -= tankmove
if keys[pygame.K_d]:
tankx += tankmove
if keys[pygame.K_w]:
tanky -= tankmove
if keys[pygame.K_s]:
tanky += tankmove
tank(tankx,tanky)
pygame.display.update()
gameloop()
I want the player to be able to use "a" and "d" to move the tank horizontally.

The event loop is executed only when an event occurs. This means it is executed when a key is pressed or a key is released — however, when a key is held down, no event occurs and the event loop is not executed.
You've got to evaluate the key presses in the main loop (in scope of gameloop) rather than in the event loop:
e.g.
def gameloop():
# [...]
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
# <--
keys= pygame.key.get_pressed()
if keys[pygame.K_a]:
tankx -= tankmove
if keys[pygame.K_d]:
tankx += tankmove
if keys[pygame.K_w]:
tanky -= tankmove
if keys[pygame.K_s]:
tanky += tankmove
tank(tankx,tanky)
pygame.display.update()
Note: pygame.key.get_pressed() returns the current states of the keys and the states are evaluated and updated when pygame.event.get() is called.
The position of the tank is reset at the begin of the frame, because the variables tankx and tanky are set at the begin of gameloop:
def gameloop():
#[...]
tankx = 100
tanky = 100
Define the variables in global scope, and use the global statement to access them.
Decrease the speed of the tank, because it would move very rapidly (tankmove = 1).
The pygame.init() should be called once only, at the begin of application.
e.g.
def gameloop():
global tankx, tanky, tankmove
tankwidth = 40
tankheight = 20
turretwidth = 5
wheelwidth = 5
time = pygame.time.get_ticks()
screen.fill(white)
# [...]
pygame.init()
tankx = 100
tanky = 100
tankmove = 1
run = True
while run:
gameloop()
I can move the tank with a randomized background, but the program keeps on drawing a new tank. To fix this, I added a screen.fill(white). That fixes the drawing problem, but now I have no background.
Don't draw the random background to the window. Create a pygame.Surface and draw the random background to the surface.
.blit the background surface to the screen in every frame:
background_surface = pygame.Surface((widht, height))
# draw background to "background_surface" rather then "screen"
# [...]
def gameloop():
# [...]
# blit background instead of screen.fill(white)
screen.blit(background_surface, (0, 0))
# [...]

Pygame - Movement drift

I currently have an object that has code to rotate it around its center and move it around (bby altering its pos values).
However I want to make it so that if up arrow is pressed, it will accelerate in the direction its facing and when its released it will decelerate again back to 0. In the code I use a dt value for the change in time.
I tried clocking the time when a button is pressed and released and use that as the dt value, using this method the dT value can be negative. I also think this wouldn't work because then the rocket would receive let's say a dT value of 1 sec and update its velocity to go really fast instead of having a smooth acceleration/deacceleration.
class Rocket:
def __init__(self, image, pos, angle):
self.image = pygame.image.load(image)
self.imageDimensions = self.image.get_rect()
self.angle = angle
self.pos = pos
self.center = (self.pos[0], self.pos[1])
self.velocity = [0, 0]
self.acceleration = [0, 0]
self.angularVelocity = 0
self.angularAcceleration = 0
self.isAccelerating = False
self.thrust = 50
def draw(self, surface):
rotatedImg = pygame.transform.rotate(self.image, self.angle)
rotatedImgDimensions = rotatedImg.get_rect()
#display image
surface.blit(rotatedImg, (self.pos[0] - rotatedImgDimensions.center[0], self.pos[1] - rotatedImgDimensions.center[1]))
def update(self, dt):
#update angle
self.angularVelocity += self.angularAcceleration * dt
self.angle += self.angularVelocity * dt
#if accelerating update the acceleration
if self.isAccelerating:
self.acceleration[0] -= self.thrust * math.sin(math.radians(self.angle))
self.acceleration[1] -= self.thrust * math.sin(math.radians(self.angle))
#update velocity
self.velocity[0] += self.acceleration[0] * dt
self.velocity[1] += self.acceleration[1] * dt
#update position
self.pos[0] += self.velocity[0] * dt
self.pos[1] += self.velocity[1] * dt
So in short I expect the rocket to accelerate forward when I press the up arrow, deaccelerate to 0 when I press the down arroy and rotate left and right when pressing arrow left and right.
Please note that the above class is in a different file named Objects.py
Thank you!!
Here is the rest of the code:
import pygame
from pygame.locals import *
import math
import Objects
#colors
WHITE = (255,255,255)
BLACK = (0,0,0)
TRANSPARENT = (0,0,0,0)
#size window
Width, Height = (1280,720)
#Main menu
def game_intro():
intro = True
while intro:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
quit()
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
intro = False
screen.fill(BLACK)
FPS = 30
#initialise pygame
pygame.init()
fpsClock = pygame.time.Clock()
screen = pygame.display.set_mode((Width, Height))
pygame.display.set_caption("Rockets and Missiles")
#Add players
Rocket1 = Objects.Rocket("rocket.png", [100, 100], 0) #start at pos 50,50
#run main menu first
game_intro()
run = True
while run:
screen.fill(BLACK)
Rocket1.draw(screen)
#event handler
pressed = pygame.key.get_pressed() #list with all pressed keys
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.KEYDOWN:
Time0 = pygame.time.get_ticks()
if event.type == pygame.KEYUP:
Time1 = pygame.time.get_ticks()
if pressed[pygame.K_UP]:
dT = Time1 - Time0
print(dT)
Rocket1.update(dT)
pygame.display.update()
fpsClock.tick(FPS)
pygame.quit()
quit()

I don't think you have a very useful definition of dT. As far as I can tell you only call Rocket.update() when a key is pressed, the rockets need to update every frame with small dT if you want smooth motion. Without calling update() in your rocket class more consistently you will not get the nice motion you want.
I suggest something like this for your main loop:
dT = 1/FPS
while run:
screen.fill(BLACK)
Rocket1.draw(screen)
#event handler
pressed = pygame.key.get_pressed() #list with all pressed keys
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if pressed[pygame.K_UP]:
Rocket1.ChangeCurrentAcceleration()
Rocket1.update()
pygame.display.update()
fpsClock.tick(FPS)
For some new ChangeCurrentAcceleration() function that adds to the acceleration in your rocket, you can then change update() to assume that it already has the proper acceleration from thrust and calculates new velocity and position from there (maybe add a 0.95* multiplier to accel so it naturally slows down).

I do not think measuring the time the button is pressed is the correct approach. Each iteration of the main loop corresponds to a fixed amount of time, and to produce an animation you want to move the rocket by that fixed amount of time each iteration. So no need to calculate a dt the way you are doing. You already have it, and it's equal to 1/FPS.
What you want to do usually is to set some velocity / acceleration for you rocket. Now they are all 0, but you should set a fixed value different from zero: how much you want it to be faster, or how much faster do you want it to accelerate, when the key button is pressed.
And when the key button corresponding is pressed, call the update method to calculate the new position / angle based on that velocity / acceleration and then redraw the rocket, considering that the time passed is 1/FPS.
And you also need two method to update separately linear motion and rotation. The way is now, you cannot separate the movements based on different keys.

Thanks guys for helping out, i didnt realise this part :D
However i want to answer my own question for people visiting this page later on.
A perhaps better way of doing it is to get the time it took the software to go over each iteration and using that as dT. it would look like the following: BBefore the main loop:fpsClock = pygame.time.Clock()
The main loop:
while run:
screen.fill(BLACK)
Rocket1.draw(screen)
#draw missiles
for missile in Missiles:
missile.draw(screen)
#event handler
pressed = pygame.key.get_pressed() #list with all pressed keys
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if pressed[K_UP]:
Rocket1.acceleration = [0, -100]
if pressed[K_DOWN]:
Rocket1.acceleration = [0, 100]
if pressed[K_RCTRL]:
Missiles.append(Objects.Missile("missile.png", Rocket1.pos, Rocket1.angle))
dT = fpsClock.get_time()
Rocket1.update(dT/1000)
pygame.display.update()
fpsClock.tick(FPS)

How do I detect the collision of two sprites using pygame?

This is my code so far, I can move and it places out a blip to pick up, I just need to know how to register that and move the blip to a new random spot!
I am very new to pygame and not 100% fluent in python either, but I'm decent. If there are pdf:s good for intermediate coders when it comes to python that would be wonderful!
import sys, pygame, os, math
from random import randint
pygame.init()
size = width, height = 800, 600
speed = [2, 2]
black = 1, 1, 1
screen = pygame.display.set_mode(size)
pygame.display.set_caption('Pick up the squares!')
UP='up'
DOWN='down'
LEFT='left'
RIGHT='right'
ball = pygame.image.load("ball.png")
ballrect = ball.get_rect()
ballx = 400
bally = 300
blip = pygame.image.load("blip.png")
bliprect = blip.get_rect()
blipx = randint(1,800)
blipy = randint(1,600)
background = pygame.Surface(screen.get_size())
background = background.convert()
background.fill((250, 250, 250))
clock = pygame.time.Clock()
while 1:
for event in pygame.event.get():
if event.type == pygame.QUIT: sys.exit()
keys = pygame.key.get_pressed()
if keys[pygame.K_LEFT]:
ballx -= 5
if keys[pygame.K_RIGHT]:
ballx += 5
if keys[pygame.K_UP]:
bally -= 5
if keys[pygame.K_DOWN]:
bally +=5
screen.fill(black)
screen.blit(ball, (ballx,bally))
screen.blit(blip, (blipx, blipy))
pygame.display.update()
clock.tick(40)

Use the colliderect method of rectangles:
if ballrect.colliderect(bliprect):
print 'Do something here'

A basic collision detection works like this (assuming you are working with two rectangles):
def does_collide(rect1, rect2):
if rect1.x < rect2.x + rect2.width and rect1.x + rect1.width > rect2.x \
and rect1.y < rect2.y + rect2.height and rect1.height + rect1.y > rect2.y:
return True
return False
Fortunately Pygame is packed with such methods, so you should go with #MalikBrahimi's answer - using colliderect function call, which will do the math for you.

You can also try using pygame.sprite.spritecollide():
if pygame.sprite.spritecollide(a, b, False):
pass
#Do something
a here is your variable name for the class for one of the sprites in the collision. b here is the group that your second sprite will be. You can set the last one to True, which will remove the sprite from the group. Setting to False will keep it the way it is. Here is an example:
if pygame.sprite.spritecollide(my_ball, ballGroup, False):
Ball.speed[0] = -Ball.speed[0]
hit.play()
Ball.move()
The variable name for my sprite is my_ball. The group containing the other sprite(s) in this collision is ballGroup. I set the last one to False to keep all the sprites on the surface. If I set to True, the sprite from ballGroup will be removed from the group and screen. I hope this helps you!