bevel_join
if(m_line_join == round_join || m_line_join == bevel_join)
stroke->line_join(agg::bevel_join);
case agg::bevel_join:
property->AddOption(agg::bevel_join, "Bevel");
property->AddOption(agg::bevel_join, "Bevel");
return agg::bevel_join;