import lib
import math

class BiLinear(lib.Interpolator):
    def get_pixel(self, pic, x, y, r, qx, qy):
        leftx = math.floor(x)
        rightx = math.ceil(x)
        topy = math.floor(y)
        bottomy = math.ceil(y)
        
        left = pic.at(leftx, topy)
        right = pic.at(leftx, topy)
        dist = x % 1
        top = (left * (1 - dist) + right * dist)
        
        left = pic.at(leftx, bottomy)
        right = pic.at(leftx, bottomy)
        bottom = (left * (1 - dist) + right * dist)
        
        dist = y % 1
        pix = (top * (1 - dist) + bottom * dist)
        
        return pix