我正在准备自动化数据库关系文档，使用的工具是graphviz。我的问题是输出图像中节点的位置不够优化，并且有许多不必要的边交叉。是否有方法对图进行优化，使结果具有最小的边交叉？
digraph structs {
node [shape=Mrecord];
overlap="false";
splines="true";
layout=sfdp;
rankdir=LR;
ttype[label="::: ttype :::|<id>id|<table_name>table_name|<type_name>type_name|<synopsis>synopsis"];
tevents[label="::: tevents :::|<id>id|<id_tcases>id_tcases|<id_ttype>id_ttype|<synopsis>synopsis|<expiredate>expiredate|<open>open"];
toperationlog[label="::: toperationlog :::|<id>id|<executiondate>executiondate|<executiontime>executiontime|<query>query|<id_tusers>id_tusers"];
tdocuments[label="::: tdocuments :::|<id>id|<id_tcases>id_tcases|<id_ttype>id_ttype|<path>path|<creationdate>creationdate"];
tcustomers_cases[label="::: tcustomers_cases :::|<id_tcustomers>id_tcustomers|<id_tcases>id_tcases"];
tcases[label="::: tcases :::|<id>id|<creationdate>creationdate|<incomingdate>incomingdate|<clousuredate>clousuredate|<synopsis>synopsis|<notes>notes|<id_ttype>id_ttype|<id_tusers>id_tusers"];
tusers[label="::: tusers :::|<id>id|<username>username|<password>password|<firstname>firstname|<lastname>lastname|<role_id>role_id"];
tcustomers[label="::: tcustomers :::|<id>id|<firstname>firstname|<lastname>lastname|<email>email|<phone>phone|<mobile>mobile|<address>address"];
tevents:id_tcases -> tcases:id [arrowhead="none"];
tevents:id_ttype -> ttype:id [arrowhead="none"];
toperationlog:id_tusers -> tusers:id [arrowhead="none"];
tdocuments:id_tcases -> tcases:id [arrowhead="none"];
tdocuments:id_ttype -> ttype:id [arrowhead="none"];
tcustomers_cases:id_tcustomers -> tcustomers:id [arrowhead="none"];
tcustomers_cases:id_tcases -> tcases:id [arrowhead="none"];
tcases:id_ttype -> ttype:id [arrowhead="none"];
tcases:id_tusers -> tusers:id [arrowhead="none"];
}