DrawBot: A moving tribute to Ellsworth Kelly's "Seine" (1951).

EllsworthKellySeine.py

# A moving tribute to Ellsworth Kelly's "Seine" (1951).

from random import seed  # seed() allows us to get repeatable pseudo-noise

def expandGrid(pixels):
    assert len(pixels) % 2
    mid = len(pixels) // 2
    midColumn = pixels[mid]
    pixels.insert(mid + 1, list(midColumn))
    pixels.insert(mid + 0, list(midColumn))
    del pixels[0]
    del pixels[-1]

def killPixels(pixels, howMany=0.3):
    nPixelsX = len(pixels)
    nPixelsY = len(pixels[0])
    mid = nPixelsX//2
    for i in range(nPixelsX):
        if i == mid:
            continue
        dist = (abs(i-mid) / mid)
        for k in range(int(round(dist*howMany*nPixelsY))):
            j = randint(0, nPixelsY-1)
            pixels[i][j] = 0


canvasSize = 500

nPixelsX = 35 # must be odd
nPixelsY = 45
pixelX = canvasSize/nPixelsX
pixelY = canvasSize/nPixelsY

pixels = [[1 for i in range(nPixelsY)] for j in range(nPixelsX)]  # create a grid of black pixels

nFrames = nPixelsX//2

# prerun, to get the correct pixel state for the actual first frame
for frame in range(nFrames):
    seed(frame)  # restart the random number generator with the frame number
    expandGrid(pixels)
    killPixels(pixels)

for frame in range(nFrames):
    seed(frame)  # restart the random number generator with the frame number
    newPage(canvasSize, canvasSize)
    fill(219/255, 202/255, 174/255)
    rect(0, 0, canvasSize, canvasSize)
    fill(0)
    stroke(0)
    strokeWidth(0.7)
    
    expandGrid(pixels)
    killPixels(pixels)

    for j in range(nPixelsY):
        for i in range(nPixelsX):
            x = i * pixelX
            y = j * pixelY
            if pixels[i][j]:
                rect(x, y, pixelX, pixelY)

if nFrames > 20:
    saveImage("EllsworthKellySeine" + ".gif")