Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
566 views
in Technique[技术] by (71.8m points)

python - How to render Mandelbrot Set faster?

I'm currently drawing the Mandelbrot set pixel by pixel with PhotoImage and tkinter. I'm using basically the algorithm directly with no modifications. Are there methods to make the calculation faster? Maybe filling in large areas of color quickly, or precalcuating constants?

Part of the code:

ITERATIONS = 50
WIDTH, HEIGHT = 600, 600
CENTER = (-.5, 0)
DIAMETER = 2.5

def mandel(c):
    z = 0
    for i in range(ITERATIONS):
        z = z**2 + c
        if abs(z) > 2:
            return i     
    return ITERATIONS

root = Tk()
canvas = Canvas(root, width=WIDTH,height=HEIGHT)
canvas.pack()
img = PhotoImage(width=WIDTH, height=HEIGHT)
canvas.create_image((WIDTH/2, HEIGHT/2), image=img, state="normal")


real = CENTER[0] - 0.5 * DIAMETER
imag = CENTER[1] - 0.5 * DIAMETER

def color(i):
    colors = ("#0000AA", "#88DDFF", "#FF8800", "#000000")
    if i == ITERATIONS:
        return colors[-1]
    else:
        choice = (i//2) % len(colors)
    return colors[choice]

for x in range(WIDTH):
    for y in range(HEIGHT):
        i = mandel(complex(real, imag))

        img.put(color(i), (x, HEIGHT-y))

        imag += DIAMETER / HEIGHT
    imag = CENTER[1] - 0.5 * DIAMETER
    real += DIAMETER / WIDTH

mainloop()
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Setting one pixel at a time is likely the main source of the slowdown. Instead of calling put for each pixel, computer a whole row of pixels, or an entire matrix of pixels, and then call put one time at the end of the loop.

You can find an example here, among other places: https://web.archive.org/web/20170512214049/http://tkinter.unpythonic.net:80/wiki/PhotoImage#Fill_Many_Pixels_at_Once


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...