Dependency Lines
Available in: All plans
Last updated: 05-Mar-2026
Overview
Dependency lines connect Gantt bars to show predecessor/successor relationships. Kazinex draws lines between the four standard relationship types used in Primavera P6 and Microsoft Project. Critical-path relationships are rendered in a distinct colour so you can trace the driving path visually.
Relationship Types
| Type | Abbreviation | Description | Line Routing |
|---|---|---|---|
| Finish to Start | FS | Successor starts after predecessor finishes | Connects predecessor's right edge to successor's left edge |
| Start to Start | SS | Both activities start together | Connects predecessor's left edge to successor's left edge |
| Finish to Finish | FF | Both activities finish together | Connects predecessor's right edge to successor's right edge |
| Start to Finish | SF | Successor finishes when predecessor starts | Connects predecessor's left edge to successor's right edge |
Lag and Lead
Relationships can include lag (positive delay) or lead (negative lag). The dependency line offset reflects the lag visually — a line with lag will show a gap between the connected bars.
| Term | Meaning | Example |
|---|---|---|
| Lag | Delay after the driving relationship | FS + 5d: successor starts 5 days after predecessor finishes |
| Lead | Overlap before the relationship completes | FS − 3d: successor starts 3 days before predecessor finishes |
Appearance Settings
| Property | Default Value |
|---|---|
| Normal line colour | Slate (rgba(100, 116, 139, 0.85)) |
| Critical line colour | Red (rgba(239, 68, 68, 0.9)) |
| Line width | 1.5 px |
Configure these in Gantt Settings → Chart Options → Dependencies.
Display Toggle
You can show or hide all dependency lines from the Gantt toolbar:
- Click the Display Settings dropdown in the Gantt toolbar.
- Toggle Show Dependencies on or off.
Alternatively, use the showDependencies toggle in Gantt Settings → Display.
Critical Path Highlighting
When Show Critical Path is enabled (on by default), dependency lines that form part of the critical path are drawn in the critical line colour (red). This lets you trace the longest path through the network visually.
A dependency is considered critical when its successor activity has zero or negative total float.
Reading Dependency Lines
Line Routing
Dependency lines use an orthogonal routing algorithm:
- The line exits the source bar edge (left for Start, right for Finish)
- It routes horizontally, then turns vertically
- It enters the target bar edge with an arrowhead
Arrowheads
The arrowhead always points at the successor bar, indicating the direction of the relationship.
Overlap Handling
When multiple dependencies converge on the same activity, lines are offset slightly to avoid overlap.
Step-by-Step: Inspecting a Dependency
Step 1 — Hover Over a Line
Hover over any dependency line to see a tooltip with:
- Predecessor activity ID and name
- Successor activity ID and name
- Relationship type (FS, SS, FF, SF)
- Lag value in work days
Step 2 — Click for Detail
Click any dependency line to select the relationship. The Activity Details panel (if open) will update to show the relationship tab.
Step 3 — Right-Click for Actions
Right-click a dependency line to open the context menu with options to:
- View Predecessor — Scroll to and select the predecessor activity
- View Successor — Scroll to and select the successor activity
- Edit Relationship (Editor Mode) — Modify relationship type or lag
- Delete Relationship (Editor Mode) — Remove the dependency
Tips & Best Practices
- Keep dependency lines enabled while reviewing the schedule to understand the network logic
- Use the critical-path colour to quickly identify the driving path
- Zoom in to Day or Week level when tracing complex dependency chains
- If the chart looks cluttered, temporarily hide dependencies, review bar positions, then re-enable
Troubleshooting
| Problem | Cause | Solution |
|---|---|---|
| No lines visible | Dependencies toggled off | Enable Show Dependencies in the display settings |
| All lines are the same colour | Critical path display off | Enable Show Critical Path in the display settings |
| Lines appear to connect wrong bars | Duplicate activity IDs after import | Check for duplicate task_id values in the data |
| Lines look jagged | Very coarse zoom level | Zoom in one level for better routing clarity |