# coding:utf-8

from tkinter import Tk,Canvas
import math,threading,time

class TkCube(object):
    def __init__(self):
        self.points = [[-1,1,-1],  # LeftFrontDown
                       [1,1,-1],   # RFD
                       [-1,-1,-1], # LBD
                       [1,-1,-1],  # RBD
                       [-1,1,1],   # LFU
                       [1,1,1],    # RFU
                       [-1,-1,1],  # LBU
                       [1,-1,1]]   # RBU
        self.pit   = [[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0],[0,0]] # point in 2d
        self.angle = 0
        self.speed = 1 # π/s
        self.fps   = 60
        self.dist  = [5,4] # distance between the cube's center and focal point/canvas
        self.st    = 1/self.fps # sleep time
        self.apf   = math.pi * self.speed / self.fps # angle per frame
        # init canvas
        self.tkroot = Tk()
        self.cvs = [Canvas(self.tkroot,bg='white',width=800,height=600),Canvas(self.tkroot,bg='white',width=800,height=600)]
        self.cvs[0].pack()
        self.showingCv = 0
        self.hiddenCv  = 1
    def rotate(self):
        self.angle += self.apf
        if self.angle > 2*math.pi:
            self.angle -= 2*math.pi
        radius = math.sqrt(2) # 点旋转的半径
        for pair in [[0,4,-math.pi/4],
                     [1,5,math.pi/4],
                     [2,6,math.pi*3/4],
                     [3,7,-math.pi*3/4]]: # rotate in pairs
            center = [radius*math.sin(self.angle+pair[2]),radius*math.cos(self.angle+pair[2])]
            # x
            self.points[pair[0]][0] = center[0]
            self.points[pair[1]][0] = center[0]
            # y
            self.points[pair[0]][1] = center[1]
            self.points[pair[1]][1] = center[1]
    def draw(self):
        # project points into 2D canvas 投影到2D
        for pt in range(8):
            rate = self.dist[1]/(self.dist[0]+self.points[pt][1])
            scale = 200
            self.pit[pt][0] = self.points[pt][0]*rate*scale
            self.pit[pt][1] = self.points[pt][2]*rate*scale
        self.cvs[self.hiddenCv].delete('all')
        # for dcp,nps in [[1,[0,3,5]], # drawing central point:以1,2,4,7四个点为中心,分别连接相邻的三个点即可绘成正方体
        #             [2,[0,3,6]],
        #             [4,[0,5,6]],
        #             [7,[3,5,6]]]:
        # 不知道为什么上面的画不出正确的正方体,底面是对角线不是棱┑(￣Д ￣)┍
        for dcp,nps in [[1,[0,2,5]], # drawing central point:以1,2,4,7四个点为中心,分别连接相邻的三个点即可绘成正方体
                        [2,[1,3,6]],
                        [0,[3]],
                        [4,[0,5,7]],
                        [7,[3,4,6]],
                        [6,[5]]]:
            for np in nps: # nearby point
                self.cvs[self.hiddenCv].create_line(self.pit[dcp][0]+400,self.pit[dcp][1]+300,self.pit[np][0]+400,self.pit[np][1]+300) # 因为坐标原点在左上角,让x和y分别加400和300让画面在窗口中心
        # 切换canvas
        self.cvs[self.showingCv].pack_forget()
        self.cvs[self.hiddenCv].pack()
        self.showingCv,self.hiddenCv = self.hiddenCv,self.showingCv
    def run(self):
        while True:
            # self.rotateThread = threading.Thread(target=self.rotate)
            # self.rotateThread.run()
            # self.drawThread = threading.Thread(target=self.draw)
            # self.drawThread.run()
            self.rotate()
            self.draw()
            # print(self.points)
            time.sleep(self.st)
    def start(self):
        self.runThread = threading.Thread(target=self.run)
        self.runThread.start()
        self.tkroot.mainloop()

if __name__ == '__main__':
    tc = TkCube()
    tc.start()