对于线长的(x,y)像素坐标，调整角度变成圆形

Question

I have have a function to generate pixel coordinates of a line of a given angle and pixel length.

    # Start position of line
    lineStartX = 100
    lineStartY = 100

    # Length of line in pixels
    lineLength = 100

    # Set angle of line
    angle = 0

    for pixel in range(lineLength):

        # Next pixel with angle adjustment
        endy = (pixel + 1) * math.sin(math.radians(angle))
        endx = (pixel + 1) * math.cos(math.radians(angle))

        # Add next pixel with angle adjustment to line start coordinates
        Xcoordinate = lineStartX + (endx)
        Ycoordinate = lineStartY + (endy)

How can i adjust the angle of each concurrent pixel coordinate to form a circle?

I've tried adjusting the angle incrementally for each pixel but it only partially completes the circle, I'm not sure what to do next.

        angle += 0.10

Update: When i increment the angle as suggested:

        angle += 2 * np.arcsin(math.pi / lineLength)

The circle still only partially completes

Answer 1

Should the line be a circle, the length equal would its circumference. Since drawing a perfect circle on a pixel matrix is not possible, some approximation rules will be in order. You could try incrementally adjusting the angle not by 0.10 but by

2 * arcsin(pi / length)

to make the spiral's ends meet:)