■

お絵描きプログラム。
左ドラッグで線を描く、右ドラッグで回す。
三角関数ですよ！
…なんかよくわかんないから不思議なプログラムになってる気がするけど。
回転前。

回転後。

#!/usr/bin/env python

import Tkinter
import math

class rollTest:
    def __init__(self):
        self.window = Tkinter.Tk()
        self.width = 800
        self.height = 600
        self.canvas = Tkinter.Canvas(self.window,bg="white",
                                     width=self.width,height=self.height)
        self.canvas.bind("<ButtonPress-1>",self.pressCanvas1)
        self.canvas.bind("<B1-Motion>",self.motionCanvas1)
        self.canvas.bind("<ButtonPress-2>",self.pressCanvas2)
        self.canvas.bind("<B2-Motion>",self.motionCanvas2)
        self.canvas.bind("<ButtonPress-3>",self.pressCanvas3)
        self.canvas.bind("<B3-Motion>",self.motionCanvas3)
        self.lines = []
        self.canvas.pack()
        self.window.mainloop()
        
    def cnvMap(self,x,y):
        return (x-self.width/2,y*-1+self.height/2)

    def cnvCanvas(self,x,y):
        return (x+self.width/2,(y-self.height/2)*-1)

    def roll(self,x,y,degree):
        (orgX,orgY) = self.cnvMap(x,y)
        orgR = math.sqrt(math.pow(orgX,2)+math.pow(orgY,2))
        orgTheta = math.atan2(orgY/orgR,orgX/orgR)
        theta = math.radians(degree)+orgTheta
        x = math.cos(theta)*orgR
        y = math.sin(theta)*orgR
        return self.cnvCanvas(x,y)

    def pressCanvas1(self,event):
        self.x = event.x
        self.y = event.y

    def pressCanvas2(self,event):
        pass

    def pressCanvas3(self,event):
        x,y = self.cnvMap(event.x,event.y)
        r = math.sqrt(math.pow(x,2)+math.pow(y,2))
        self.rollOrgTheta = math.atan2(x/r,y/r)
        print self.rollOrgTheta

    def motionCanvas1(self,event):
        line = self.canvas.create_line(self.x,self.y,event.x,event.y,
                                       fill="red",width=5)
        self.lines.append((line,self.x,self.y,event.x,event.y))
        self.x = event.x
        self.y = event.y
    def motionCanvas2(self,event):
        pass

    def motionCanvas3(self,event):
        x,y = self.cnvMap(event.x,event.y)
        r = math.sqrt(math.pow(x,2)+math.pow(y,2))
        theta = self.rollOrgTheta - math.atan2(x/r,y/r) 
        for ii in range(len(self.lines)):
            line,sx,sy,ex,ey = self.lines[ii]
            sx,sy = self.roll(sx,sy,math.degrees(theta))
            ex,ey = self.roll(ex,ey,math.degrees(theta))
            self.canvas.coords(line,sx,sy,ex,ey)
            self.lines[ii] = (line,sx,sy,ex,ey)
        self.rollOrgTheta = math.atan2(x/r,y/r)

rollTest()