Why does my PyGame rotation look so goofy?-CodePudding

I am trying to rotate an image in PyGame, and I don't know how to describe it, but it's very goofy. Here's my code.

import sys, pygame
pygame.init()

size = width, height = 600, 600
green = 50, 168, 82

screen = pygame.display.set_mode(size)


class Capybara:
    def __init__(self, size_multiplier):
        self.capybara = pygame.image.load('capybara.gif')
        self.x = 300
        self.y = 300
        self.o_size = 92, 206
        self.new_size = (self.o_size[0] * size_multiplier,self.o_size[1] * size_multiplier)
        self.capybara = pygame.transform.scale(self.capybara, self.new_size)
        self.base_capybara = self.capybara
        self.rotation = 0

    def rotate(self, amount):
        self.rotation  = amount
        if self.rotation == 361:
            self.rotation = 0
        elif self.rotation == -1:
            self.rotation = 360
        print(self.rotation)
        self.capybara = pygame.transform.rotate(self.base_capybara, self.rotation)

capybara = Capybara(0.8)

fpsClock = pygame.time.Clock()

rotate_l = False
rotate_r = False

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()

            quit()

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                rotate_l = True
                if rotate_r:
                    rotate_r = False
            if event.key == pygame.K_RIGHT:
                rotate_r = True
                if rotate_l:
                    rotate_l = False

        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                rotate_l = False
            if event.key == pygame.K_RIGHT:
                rotate_r = False

    if rotate_l:
        capybara.rotate(-1)
    if rotate_r:
        capybara.rotate(1)

    screen.fill(green)
    screen.blit(capybara.capybara, (capybara.x - int(capybara.new_size[0]/2), capybara.y - int(capybara.new_size[1]/2)))
    pygame.display.update()
    fpsClock.tick(60)

And here's what I mean by goofy:

CodePudding user response：

It looks so "goofy, because you do not rotate around the center of the image. See

import sys, pygame
pygame.init()

size = width, height = 600, 600
green = 50, 168, 82

screen = pygame.display.set_mode(size)

class Capybara:
    def __init__(self, size_multiplier):
        self.capybara = pygame.image.load('capybara.gif')
        self.o_size = 92, 206
        self.new_size = (self.o_size[0] * size_multiplier,self.o_size[1] * size_multiplier)
        self.capybara = pygame.transform.scale(self.capybara, self.new_size)
        self.base_capybara = self.capybara
        self.rotation = 0
        self.rect = self.capybara.get_rect(center = (300, 300))

    def rotate(self, amount):
        self.rotation  = amount
        if self.rotation == 361:
            self.rotation = 0
        elif self.rotation == -1:
            self.rotation = 360
        print(self.rotation)
        self.capybara = pygame.transform.rotate(self.base_capybara, self.rotation)
        self.rect = self.capybara.get_rect(center = self.rect.center)

capybara = Capybara(0.8)

fpsClock = pygame.time.Clock()

rotate_l = False
rotate_r = False

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            quit()

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                rotate_l = True
                if rotate_r:
                    rotate_r = False
            if event.key == pygame.K_RIGHT:
                rotate_r = True
                if rotate_l:
                    rotate_l = False

        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                rotate_l = False
            if event.key == pygame.K_RIGHT:
                rotate_r = False

    if rotate_l:
        capybara.rotate(-1)
    if rotate_r:
        capybara.rotate(1)

    screen.fill(green)
    screen.blit(capybara.capybara, capybara.rect)
    pygame.display.update()
    fpsClock.tick(60)