effect.py 文件源码

def eqn(self, x, n, size):
        "Calculate paint boundary"
        if not self.side: n = 1 - n
        w, h = size
        y = 0
        xc = 0
        for d in self.drops:
            r = d[0] * w / 2
            R = 1.1 * r
            xc += r
            dx = abs(x - xc)
            if dx <= R:
                dy = sqrt(R * R - dx * dx)
                Y = (h + R) * self.posn(n, *d[1:]) + dy - R
                if Y > y: y = Y
            xc += r
        return y, self.side