grid.py 文件源码

def dust(self, pyd, pxd, y1d, x1d, y2d, x2d):   # debug
        px = radians(pxd)
        py = radians(pyd)
        x1 = radians(x1d)
        y1 = radians(y1d)
        x2 = radians(x2d)
        y2 = radians(y2d)
        p_x = x2 - x1
        p_y = y2 - y1
        something = p_x * p_x + p_y * p_y
        u = ((px - x1) * p_x + (py - y1) * p_y) / float(something)
        if u > 1:
            u = 1
        elif u < 0:
            u = 0
        x = x1 + u * p_x
        y = y1 + u * p_y
        dx = x - px
        dy = y - py
        dist = sqrt(dx * dx + dy * dy)
        return [round(abs(dist) * RADIUS, 2), round(degrees(y), 6), round(degrees(x), 6)]