tikzdraw.py 文件源码

def get_ref_centre(nodelist):
    """Choose a node as the diagram centre and find the unit distance.

    Find the shortest distance between two nodes and use it as the unit distance of the 
    diagram grid. Choose one of these two nodes as the diagram centre.

    Args:
        nodelist (list): A list of nodes

    Returns:
        The absolute position of the centre node and the unit distance of the diagram.
    """    
    centres = [node.centre for node in nodelist]
    min_d = sp.dist(centres[0], centres[1])    
    min_p0,min_p1 = centres[0], centres[1]
    for p0, p1 in itertools.combinations(centres, 2):
        d = sp.dist(p0,p1)
        if d < min_d:
            min_d = d
            min_p0,min_p1 = p0,p1   
    min_x = abs(min_p0[0] - min_p1[0])
    min_y = abs(min_p0[1] - min_p1[1])
    unit_d = max(min_x, min_y)
    return [min_p0,unit_d]