Connectors

Connectors are lines used to link shapes together, representing relationships or flows.

Drawing Connections

To connect two shapes:

  1. Select the Connector Tool from the toolbar.
  2. Hover over the first shape until connection points (small circles) appear.
  3. Click a connection point and drag to a connection point on the second shape.

Connecting Two Shapes

Smart Routing

Diagrammix3 uses smart routing algorithms (LibAvoid) to automatically route connectors around other shapes, ensuring your diagram remains clean and readable.

Smart Routing Example

Bend Points and Pin Points

You can manually control the path of a connector:

  • Bend Points: Double-click a connector to show the Connector Action Toolbar. Click the Add Bend Point (+) icon to add a new handle on the line which you can drag to reshape the path.
  • Pin Points: Click the Pin icon in the toolbar to add a "sticky" point on the connector. This ensures the line passes through a specific coordinate even if connected shapes move.

Connector Handles

Routing Modes

Available in the Inspector Panel under Connector Geometry:

  • Straight: A direct line between points.
  • Polyline: Multi-segmented lines with hard corners.
  • Orthogonal: Lines consisting only of horizontal and vertical segments.
  • Bezier: Smooth, curved lines.

Sticky Spots

Sticky spots are predefined connection points on shapes where connectors attach. They provide precise control over where lines connect.

Default Sticky Spots

Most shapes have automatic sticky spots:

  • Rectangles: Center of each edge (4 points)
  • Ellipses: Top, bottom, left, right (4 points)
  • Triangles: Each vertex and edge center

Connecting to Sticky Spots

  1. Select the Connector Tool
  2. Hover over a shape
  3. Blue circles appear showing available sticky spots
  4. Click a spot to start the connection
  5. Drag to a spot on the target shape

Custom Sticky Spots

For custom shapes, you can define your own sticky spots:

  1. Select the shape
  2. Go to Format → Edit Sticky Spots
  3. Click to add new spots on the shape boundary
  4. Drag to reposition existing spots
  5. Option-click to remove a spot

Benefits of Sticky Spots

  • Connectors stay attached when shapes move
  • Consistent connection positions across similar shapes
  • Clean, professional-looking diagrams
  • Automatic routing optimization

Arrowheads

Connectors can have arrowheads at either or both ends. Select a connector and use the Inspector to choose from 31 different arrowhead styles including:

  • Basic arrows: Standard, inflected, stick
  • UML notation: Inheritance triangles, composition diamonds
  • ERD notation: Crow's feet for cardinality
  • Decorative: Feathers, circles, bars

For a complete reference of all arrowhead types, see the Arrowheads Reference.

Line Styles

In the Inspector, you can customize:

  • Stroke color: The color of the connector line
  • Stroke width: Line thickness (1px to 10px+)
  • Dash pattern: Solid, dashed, or dotted lines
  • Start/End arrows: Choose from 31 arrowhead styles

Connector Text Labels

Add text labels to connectors to describe relationships.

Adding Labels

  1. Double-click anywhere on a connector line
  2. A text editing cursor appears
  3. Type your label text
  4. Click outside to finish

Positioning Labels

Drag labels along the connector path:

  1. Click the label to select it
  2. Drag to reposition along the line
  3. The label stays attached to the connector

Label Placement Options

In the Inspector, you can set:

  • Position: Start, middle, or end of the connector
  • Offset: Distance from the connector line
  • Rotation: Align with the connector angle or keep horizontal

Multiple Labels

You can add multiple labels to a single connector:

  • One at the start (e.g., "1")
  • One in the middle (e.g., "uses")
  • One at the end (e.g., "*")

This is particularly useful for UML relationship notation.

Connector Labels