python通过PyGame绘制图像并保存为图片文件的代码

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''' pg_draw_circle_save101.py
draw a blue solid circle on a white background
save the drawing to an image file
tested with Python 2.7 and PyGame 1.9.2 by vegaseat 16may2013
'''

import pygame as pg

# pygame uses (r, g, b) color tuples
white = (255, 255, 255)
blue = (0, 0, 255)

width = 300
height = 300

# create the display window
win = pg.display.set_mode((width, height))
# optional title bar caption
pg.display.set_caption("Pygame draw circle and save")
# default background is black, so make it white
win.fill(white)

# draw a blue circle
# center coordinates (x, y)
radius = min(center)
# width of 0 (default) fills the circle
# otherwise it is thickness of outline
width = 0
# draw.circle(Surface, color, pos, radius, width)
pg.draw.circle(win, blue, center, radius, width)

# now save the drawing
# can save as .bmp .tga .png or .jpg
fname = "circle_blue.png"
pg.image.save(win, fname)
print("file {} has been saved".format(fname))

# update the display window to show the drawing
pg.display.flip()

# event loop and exit conditions
# (press escape key or click window title bar x to exit)
while True:
for event in pg.event.get():
if event.type == pg.QUIT:
# most reliable exit on x click
pg.quit()
raise SystemExit
elif event.type == pg.KEYDOWN:
# optional exit with escape key
if event.key == pg.K_ESCAPE:
pg.quit()
raise SystemExit