msc201clipping

import matplotlib.pyplot as plt 

## Cordinates of the clipping window
X_MIN = 30
X_MAX = 100
Y_MIN = 30
Y_MAX = 100

## Initialize 4 region bit
left = 1
right = 2
bottom = 4
top = 8

class line:
    def __init__(self):
        self.visibility = 0

    def input(self):
        self.xstart = int(input("Enter x1: "))
        self.ystart = int(input("Enter y1: "))
        self.xend = int(input("Enter x2: "))
        self.yend = int(input("Enter y2: "))



def getRegCode(x,y):
    code = 0
    if(x > X_MAX):
        code |= right
    elif(x < X_MIN):
        code |= left
    elif(y < Y_MIN):
        
        code |= bottom
    elif (y >Y_MAX):
        code |= top

    return code

def evaluate_intersaction(L,out):
    slope = (L.yend - L.ystart) / (L.xend - L.xstart)
    if (out & left):
        xn = X_MIN
        yn = L.ystart + (slope)*(XMIN - L.xstart)
    elif(out & right):
        xn = X_MAX
        yn = L.ystart + (slope)*(XMAX - L.xstart)
    elif(out & bottom):
        yn = Y_MIN
        xn = L.xstart + (1/slope)*(Y_MIN - L.xstart)
    elif(out & top):
        yn = Y_MAX
        xn = L.xstart + (1/slope)*(Y_MAX - L.xstart)
    new = (xn,yn)

    return new


def decide_clipping(L: line):
    e1 = getRegCode(L.xstart,ystart)
    e2 = getRegCode(L.xend,L.yend)
    
    if e1 | e2 == 0:
        L.visibility = 0
        print("Trivially accepted: Line is fully inside of the window")
    elif (e1 & e2 != 0):
        L.visibility = 0
        print("Trivially rejected: Line is fully outside of the window")
    else:
        if(e1 != 0):
            outside = e1
        else:
            outside = e2
        new_pt = evaluate_intersaction(L,outside)
    
    return new_pt

line1 = line()
line1.input()

print(line1.xstart,line1.ystart,line1.xend,line1.yend)

plt.plot(
    [X_MIN,X_MIN,X_MAX,X_MAX,X_MIN],
    [Y_MIN,Y_MAX,Y_MAX,Y_MIN,Y_MIN]
)
plt.plot([line1.xstart,line1.xend] , [line1.ystart , line1.yend])
plt.show()