    function q = corner2DPoster(X1,X2,varargin)
    % one corner

    seti = varargin{end};
    R = seti.rCD/2;

    %p1 = -4/8; % top and left
    %l = 9/8; %length
    %w = 1/8; %width

    p1 = -5/8;
    l = 7/8;
    w = 1/8;

    %p1 = -4/8;
    %l = 5/8;
    %w = 1/16;

    p2 = p1+l; % bottom and right
    p3 = p1+w;

    q1 = (p1*R <= X1) & (X1 < p2*R) & (p1*R <= X2) & (X2 < p3*R); % top line
    q2 = (p1*R <= X1) & (X1 < p3*R) & (p3*R <= X2) & (X2 < p2*R); % left line
    q = q1 | q2;

    q = double(q);

    end