def get_border():
    '''Returns the border. 

    :return:  A tuple of 4 numbers (xmin, ymin, xmax, ymax). 
    '''

    pass


def get_canvas_height():
    '''Returns the canvas height. 

    :return:  The canvas height. 
    '''

    pass


def get_canvas_width():
    '''Returns the canvas width. 

    :return:  The canvas width. 
    '''

    pass


def get_selected_fedge():
    '''Returns the selected FEdge. 

    :return:  The selected FEdge. 
    '''

    pass


def get_time_stamp():
    '''Returns the system time stamp. 

    :return:  The system time stamp. 
    '''

    pass


def load_map(file_name, map_name, num_levels=4, sigma=1.0):
    '''Loads an image map for further reading. 

    :param file_name: The name of the image file. 
    :type file_name: str
    :param map_name: The name that will be used to access this image. 
    :type map_name: str
    :param num_levels: The number of levels in the map pyramid (default = 4). If num_levels == 0, the complete pyramid is built. 
    :type num_levels: int
    :param sigma: The sigma value of the gaussian function. 
    :type sigma: float
    '''

    pass


def read_complete_view_map_pixel(level, x, y):
    '''Reads a pixel in the complete view map. 

    :param level: The level of the pyramid in which we wish to read the pixel. 
    :type level: int
    :param x: The x coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type x: int
    :param y: The y coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type y: int
    :return:  The floating-point value stored for that pixel. 
    '''

    pass


def read_directional_view_map_pixel(orientation, level, x, y):
    '''Reads a pixel in one of the oriented view map images. 

    :param orientation: The number telling which orientation we want to check. 
    :type orientation: int
    :param level: The level of the pyramid in which we wish to read the pixel. 
    :type level: int
    :param x: The x coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type x: int
    :param y: The y coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type y: int
    :return:  The floating-point value stored for that pixel. 
    '''

    pass


def read_map_pixel(map_name, level, x, y):
    '''Reads a pixel in a user-defined map. 

    :param map_name: The name of the map. 
    :type map_name: str
    :param level: The level of the pyramid in which we wish to read the pixel. 
    :type level: int
    :param x: The x coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type x: int
    :param y: The y coordinate of the pixel we wish to read. The origin is in the lower-left corner. 
    :type y: int
    :return:  The floating-point value stored for that pixel. 
    '''

    pass
