如何调整PlantUML语法避免连线重合，优化布局可读性？

1. 用rank指令强制节点层级 #

通过rank same将多个卡片绑定到同一水平/垂直层级，避免自动布局算法随意调整位置，从根源减少连线交叉。

@startuml
' 让A、B、C处于同一水平层级
rank same A, B, C
card "用户管理" as A
card "权限控制" as B
card "日志审计" as C
card "系统核心" as D

A --> D
B --> D
C --> D
@enduml

2. 用order指令定义排列顺序 #

指定卡片的绘制顺序，引导PlantUML按预设逻辑布局，替代默认的自动排序规则，降低连线交叉概率。

@startuml
' 按A→B→D→C的顺序绘制节点
order A, B, D, C
card "前端页面" as A
card "API网关" as B
card "数据库" as C
card "业务服务" as D

A --> D
B --> D
D --> C
@enduml

3. 手动指定节点绝对坐标（精准控制） #

使用pos(x,y)语法直接定义卡片的位置坐标，完全摆脱自动布局的限制，适合结构复杂的场景。

@startuml
card "登录模块" as A pos(0, 0)
card "注册模块" as B pos(150, 0)
card "用户中心" as C pos(75, 120)
card "数据统计" as D pos(75, -120)

A --> C
B --> C
A --> D
B --> D
@enduml

4. 隐藏节点辅助布局 #

添加不可见的hidden节点作为布局锚点，引导连线绕开交叉区域，优化连线走向。

@startuml
card "订单创建" as A
card "订单支付" as B
card "订单发货" as C
card "订单完成" as D
node hidden as H ' 隐藏节点作为中转

rank same A, H, B
A --> H
H --> C
B --> D
C --> D
@enduml

内容的提问来源于stack exchange，提问作者User9527