BanpakuLogo.py

import numpy as np
import matplotlib.pyplot as plt 
import matplotlib.patches as patches

def ellipse(ax,x,y,width,height,angle=0,color="k"):
    e = patches.Ellipse(xy = (x,y), width = width, height = height,
                    angle = angle, color = color)
    ax.add_patch(e)

def plot_rw():
    for pos in r_pos:
        ellipse(ax,pos[0],pos[1],2*pos[2],2*pos[3],color="r")

    for pos in w_pos:
        ellipse(ax,pos[0],pos[1],2*pos[2],2*pos[3],color="w")

def plot_b_default():
    for pos in b_pos:
        ellipse(ax,pos[0],pos[1],2*pos[2],2*pos[3],color="b")

def plot_b(cx,cy):
    for i in range(N_b):
        wx = w_pos[i][0]
        wy = w_pos[i][1]
        wθ = calc_θ(cx - wx,cy - wy)

        bx = wx + br[i] * np.cos(wθ)
        by = wy + br[i] * np.sin(wθ)

        ellipse(ax,bx,by,2*b_pos[i][2],2*b_pos[i][3],color="b")
        b_pos[i][0] = bx
        b_pos[i][1] = by
    return b_pos
    
def calc_θ(cx,cy):
    return np.sign(cy)*np.arccos(cx/np.sqrt(cx**2+cy**2))

def calc_r(cx,cy):
    return np.sqrt(cx**2+cy**2)

def set_axis():
    plt.xlim([0,512])
    plt.ylim([0,512])
    
    plt.gca().invert_yaxis()
    plt.axis("off")

def press(e):
    global key

    if key == "":
        key = e.key
    else:
        key = ""

def motion(event):
    global b_pos,key
    if (event.xdata) is None or (event.ydata is None):
        return

    cx = event.xdata
    cy = event.ydata

    plt.cla()
    plot_rw()
    if key == "":
        plot_b_default()
    else:
        b_pos = plot_b(cx,cy)
        
    set_axis()
    plt.draw()

# https://twitter.com/3socha/status/1298182210399244289
# https://twitter.com/3socha/status/1298182261964066817

r_pos = [[223, 70, 55, 55],
         [336, 87, 70, 70],
         [389,172, 87, 39],
         [380,250, 52, 58],
         [370,365, 77, 71],
         [275,437, 65, 65],
         [180,430, 50, 50],
         [135,360, 35, 55],
         [ 93,277, 62, 62],
         [ 80,175, 53, 53],
         [155,198, 48, 48],
         [151,120, 48, 48]] 

w_pos = [[354, 62,31,31],
         [400,370,40,34],
         [267,463,23,23],
         [113,289,30,30],
         [ 67,167,26,26]]

b_pos = [[364, 49, 14,14],
         [418,362, 17,17],
         [267,476,  9, 9],
         [110,273, 13,13],
         [ 53,162, 13,13]]

N_b = len(b_pos)
br = [0]*N_b 

for i in range(N_b):
    bx = b_pos[i][0]
    by = b_pos[i][1]
    wx = w_pos[i][0]
    wy = w_pos[i][1]
    br[i] = calc_r(bx-wx,by-wy)

key = "" 

plt.close('all')
fig = plt.figure(figsize=(5, 5))
ax = fig.add_subplot(111)
set_axis()
plt.connect('motion_notify_event', motion)
plt.connect('key_press_event', press)