You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: plot_camera.m
    path of file: ./repos/machinevision-toolbox-matlab/@Camera
    
    the code of the file until where you have to start completion: %Camera.plot_camera Display camera icon in world view
%
% C.plot_camera(OPTIONS) draw a camera as a simple 3D model in the current
% figure.
%
% Options::
% 'pos
    
function h = plot_camera(c, varargin)
    
    opt.pose = c.T;
    opt.scale = [];
    opt.frustum = false;
    opt.label = false;
    opt.persist = false;
    
    [opt,arglist] = tb_optparse(opt, varargin);
    
    if isempty(opt.scale)
        % get the overall scale factor from the existing graph
        sz = [get(gca, 'Xlim'); get(gca, 'Ylim'); get(gca, 'Zlim')];
        sz = max(sz(:,2)-sz(:,1));
        opt.scale = sz / 15;
    end