使用JES（python）在圖像上的白色網格線

Question

我如何編寫使用JES在圖像上繪制“白色”網格線的程序，該圖像的水平網格線分隔為10個像素，垂直網格線分隔為20個像素？

Answer 1

是的，令人驚訝的是， addLine(picture, startX, startY, endX, endY)只能畫黑線！

因此，讓我們手動進行。 這是一個非常基本的實現：

def drawGrid(picture, color):

  w = getWidth(picture)
  h = getHeight(picture)

  printNow(str(w) + " x " + str(h))

  w_offset = 20  # Vertical lines offset
  h_offset = 10  # Horizontal lines offset

  # Starting at 1 to avoid drawing on the border
  for y in range(1, h):     
    for x in range(1, w):
      # Here is the trick: we draw only 
      # every offset (% = modulus operator)
      if (x % w_offset == 0) or (y % h_offset == 0):
        px = getPixel(picture, x, y)
        setColor(px, color)


file = pickAFile()
picture = makePicture(file) 
# Change the color here
color = makeColor(255, 255, 255) # This is white
drawGrid(picture, color)
show(picture)

注意：使用這里提供的腳本drawLine（）函數也可以更有效地實現這一點 。

輸出：

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....... ...... .......

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