如何在 Pygame 中更改图像大小？

Question

有我正在导入的图像：

look_1 = pygame.image.load('data\\png\\look1.png').convert_alpha()

我试图减少它的大小是这样的：

pygame.transform.scale()

但这似乎不是正确的方法。

Answer 1

您可以使用pygame.transform.scale或smoothscale并传递表面的新宽度和高度，或者pygame.transform.rotozoom传递将乘以当前分辨率的浮点数。

import sys
import pygame as pg

pg.init()
screen = pg.display.set_mode((640, 480))

IMAGE = pg.Surface((100, 60))
IMAGE.fill(pg.Color('sienna2'))
pg.draw.circle(IMAGE, pg.Color('royalblue2'), (50, 30), 20)
# New width and height will be (50, 30).
IMAGE_SMALL = pg.transform.scale(IMAGE, (50, 30))
# Rotate by 0 degrees, multiply size by 2.
IMAGE_BIG = pg.transform.rotozoom(IMAGE, 0, 2)


def main():
    clock = pg.time.Clock()
    done = False
    while not done:
        for event in pg.event.get():
            if event.type == pg.QUIT:
                done = True

        screen.fill(pg.Color('gray15'))
        screen.blit(IMAGE, (50, 50))
        screen.blit(IMAGE_SMALL, (50, 155))
        screen.blit(IMAGE_BIG, (50, 230))
        pg.display.flip()
        clock.tick(30)


if __name__ == '__main__':
    main()
    pg.quit()
    sys.exit()

Answer 2

您必须决定是否要使用 Usepygame.transform.smoothscale或pygame.transform.scale。在使用最近的pygame.transform.scale像素执行快速缩放时，通过像素插值将表面平滑地缩放到任何大小。 放大表面将导致锯齿状结果。缩小尺寸时，您会丢失信息（像素）。相比之下，使Surface变得模糊。pygame.transform.smoothscale
pygame.transform.scale()pygame.transform.smoothscale

pygame.transform.scale()并pygame.transform.smoothscale以相同的方式使用。它们不会缩放输入表面本身。它创建一个新表面并对新表面进行缩放“blit”。新的表面由返回值返回。他们：

1. 创建一个尺寸为 的新曲面 ( newSurface) (width, height)。
2. 缩放并复制Surface到newSurface.
3. 返回newSurface。

look_1 = pygame.image.load('data\\png\\look1.png').convert_alpha()
look_1 = pygame.transform.scale(look_1, (new_width, new_height)) 

或者

look_1 = pygame.image.load('data\\png\\look1.png').convert_alpha()
look_1 = pygame.transform.smoothscale(look_1, (new_width, new_height)) 

另请参见变换比例和缩放表面

最小的例子： replit.com/@Rabbid76/PyGame-ScaleCenter

import pygame

class ScaleSprite(pygame.sprite.Sprite):
    def __init__(self, center, image):
        super().__init__()
        self.original_image = image
        self.image = image
        self.rect = self.image.get_rect(center = center)
        self.mode = 1
        self.grow = 0

    def update(self):
        if self.grow > 100:
            self.mode = -1
        if self.grow < 1:
            self.mode = 1
        self.grow += 1 * self.mode 

        orig_x, orig_y = self.original_image.get_size()
        size_x = orig_x + round(self.grow)
        size_y = orig_y + round(self.grow)
        self.image = pygame.transform.scale(self.original_image, (size_x, size_y))
        self.rect = self.image.get_rect(center = self.rect.center)

pygame.init()
window = pygame.display.set_mode((300, 300))
clock = pygame.time.Clock()

sprite = ScaleSprite(window.get_rect().center, pygame.image.load("Banana64.png"))
group = pygame.sprite.Group(sprite)

run = True
while run:
    clock.tick(60)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    group.update()

    window.fill(0)
    group.draw(window)
    pygame.display.flip()

pygame.quit()
exit()