[Pygame] how to get my sprite rotations working properly?

[xZachtmx]

ok so im using pygame jto create a simple 2d game and i have a sprite (little triangle for now) that is always in the center and only movement it does is rotate.
here is the code:
Code:

import pygame
from pygame.locals import*
from sys import exit
pygame.init()


windowSize = 1024,768

frameRate = 50

    # initializing the game window
gameWindow = pygame.display.set_mode((windowSize)) #, FULLSCREEN ) 
pygame.display.set_caption('STARBOUND') 
screen = pygame.display.get_surface() 

#loading textures
    # ship sprites
podTex = 'shipPlaceholder.png'
podSprite = pygame.image.load(podTex).convert_alpha()



clock = pygame.time.Clock()

class ship:
    def __init__(self):
        self.shipName = "pod"

        self.xPos = 0

        self.yPos = 0

        self.position = (self.xPos, self.yPos)

        self.width = 120

        self.height = 120

        self.hull = 100

        self.hullMax = 1000

        self.energy = 1000

        self.energyMax = 1000

        self.engineSpeed = 5
        
        self.turningSpeed = 5

        self.thrustingSpeed = 0

        self.thrustingSpeedMax = 10

        self.primaryWeapon = 1

        self.secondaryWeapon = 0

        self.secondaryWeaponMax = 0

        self.angle = 0

        self.isComp = True;

        self.shipTexture = podSprite;
        

    def turn(self, amount):
        self.angle += amount
        self.shipTexture = pygame.transform.rotate(self.shipTexture, self.angle)        
       
        
    def draw(self):
        screen.blit(self.shipTexture, (self.position))
        
playerShip = ship()
playerShip.xPos = windowSize[0] / 2 - 60
playerShip.yPos = windowSize[1] / 2 - 60
playerShip.position = (playerShip.xPos, playerShip.yPos);
playerShip.turningSpeed = 90
playerShip.isComp = False


while True:
    # Limit frame speed to 50 FPS
    #
     time_passed = clock.tick(frameRate)
    
     
     ship.turn(playerShip, playerShip.turningSpeed)
    
     ship.draw(playerShip) 
            
     pygame.display.flip()

now.. i want the sprite so slowly spim at a speed of 90 degrees per second (playerShip.turningSpeed)
so it spins... but instead of it being centered... it spins out of the window:

dreamincode.net/forums/index.php?act=Attach&type=post&id=12345

How can i get it so that it stays in the middle instead of spiraling out of the window?
xZachtmx is offline Reply With Quote

[ShadenSmith]

I'm running your code on my machine and I can't seem to reproduce your problem. The ship is stationary and only rotating.

Your speed of rotation is off though. It's rotating at much more than 90 degrees per second. You are incrementing your angle by 90 each frame.


EDIT: I've discovered that the bug can be reproduced with turningSpeed is not a multiple of 90 degrees. I'll take a look at the code more closely this afternoon and try to find the problem.