Draw & Edit Paths

Start with a small number of anchors, then add detail only when the path needs it. Every extra element creates another geometric or behavioral decision to test.

Add elements

The Path Elements header provides two authoring actions:

• Add element inserts a waypoint, translation target, rotation target, or event trigger after the current selection.
• Add curve records a stroke on the field and converts it into simplified translation targets.

If nothing is selected, new elements are appended. The first and last elements are restricted to waypoint or translation types so the path begins and ends with a valid position.

Select and edit

Click an element on the canvas or in the list. The Element Properties section then exposes the fields relevant to its type:

Element	Current editor fields
Waypoint	X, Y, Handoff Radius, Rotation, Profiled Rotation, linked-element controls
Translation	X, Y, Handoff Radius, linked-element controls
Rotation	Rotation, Profiled Rotation, Rotation Pos (0-1)
Event Trigger	Event Pos (0-1), Lib Key

Typing a coordinate is best for a known scoring pose. Dragging is best for quick geometry iteration. Use both: drag for the shape, then enter the exact final value.

Canvas interactions

Interaction	Result
Mouse wheel/trackpad scroll	Zoom around the pointer
Drag empty field space	Pan
Click an element	Select it and reveal properties
Drag an anchor	Change its X/Y position
Drag a selected rotation handle	Change heading
Click empty canvas	Clear selection
Right-click empty field or an anchor	Open linked-element actions

Locked linked elements cannot be moved from an individual path. Edit them in the linked-element manager or unlock them intentionally.

Reorder or remove

Drag an element row in Path Elements to reorder it. With a row selected:

• Arrow Up / Arrow Down moves it in path order.
• Delete / Backspace removes it.

Reordering an anchor changes the segment that surrounding rotation targets and events belong to. Re-check every t_ratio marker and ranged constraint after a structural edit.

Draw a curve

Choose Add curve, draw the intended centerline on the field, and release. BLine Web simplifies the stroke into no more than 18 translation targets and applies automatic maximum-velocity ranged constraints across the inserted ordinal span.

After drawing:

1. Remove points that do not materially improve the shape.
2. Move points away from obstacles and handoff locations that are hard to reach.
3. Review every automatic maximum-velocity ranged constraint.
4. Replace an endpoint translation with a waypoint when final heading matters.
5. Simulate, then validate in WPILib simulation and on the robot.

The curve tool is an authoring shortcut, not a spline runtime. The exported path is still a polyline.

Use the collection context

Other paths in the active collection appear as ghost outlines. Use them to align shared starts/endpoints or avoid overlapping route families. Hover an outline for its name and click to make it active.

For a coordinate that must remain identical across paths, use a linked element instead of visually aligning two independent points.

Path-design habits

• Use translation targets to shape motion when heading does not matter.
• Keep intermediate anchors away from bumps or objects where the robot should preserve momentum.
• Slow before sharp direction changes; geometry alone does not create a feasible turn.
• Use a waypoint at a scoring endpoint where both pose components matter.
• Keep event markers in increasing t_ratio order within each segment.
• Prefer a few meaningful anchors over many tiny segments.

Verify after every structural edit

• First and last elements still represent the intended poses.
• Rotation/event markers belong to the intended segment.
• Translation and rotation constraint ordinals still cover the intended elements.
• Automatic ranged constraints from the optimizer are not stale.
• Simulation starts, finishes, and shows the intended headings.

Next: Constraints & Optimizer.