5. Attribute Modes

These modes allow to add various Road Attributes to Road Lane, which can be used for procedural generation or any other purposes (see the Road Attributes section):

By default, two types of attributes are available: speed limit and road markings. To learn how to create new attribute types, see Attribute Profile. To add a new attribute for a lane, select the appropriate mode in the Road Editing Modes menu, select the required Road Lane, and select Create ATTRIBUTE_NAME from the context menu. Then, add the required Attribute Keys from the same context menu:

In the Details Panel, in the Selection group, you can edit the selected Attribute Key:

5.1. Road Mark Attribute

Road Mark Attribute is one of the Road Attributes types that is available “out of the box” and allows you to add a Mark attribute to Road Lane, which is used in Procedural Generation to generate road markings. Each Attribute Key is assigned a road marking type, which can be selected in Profile. Or you can create a new type on the spot (Profile Source -> Use Custom):

If you need to remove markings for any of the sections on Road Lane, set Profile to empty:

To add new road marking profiles, see Lane Mark Profiles.

5.2. Curb Cut Attribute (Pro)

This attribute allows to create curb cuts on sidewalks:

5.3. Landscape Attribute (Pro)

The Landscape Attribute controls how the Unreal Engine landscape deforms along the road. Add it to the center lane (lane index 0) of a URoadSplineComponent that has a landscape assigned. Only one Landscape Attribute is allowed per lane section. Keys use cubic interpolation, so height and falloff transition smoothly between keys.

Property	Default	Description
LayerFactor	1.0	Landscape layer blend weight at this key [0–1]
SideFalloff	1000	Distance (in cm) over which the landscape modification fades out laterally
SideOffset	0	Lateral offset of the deformation zone from the reference line
HeightOffset	50	Z-height offset applied to landscape vertices under the road

5.4. Sidewalk Height Attribute

The Sidewalk Height Attribute adjusts the Z-height of sidewalk mesh vertices at specific positions along the lane — for example, to create ramps or sloped curb approaches. It modifies existing mesh vertices; it does not add new geometry, so it works best when keys are not placed too close together.

Can only be added to sidewalk lanes (FRoadZoneSidewalk zone type).
Keys use cubic interpolation for smooth height transitions.

Property	Range	Description
Height	−100 to +100 cm	Z-offset applied to sidewalk vertices at this key position

5.5. Polygon Attribute (Pro)

The Polygon Attribute places custom 2D polygon shapes on a lane at specific arc-length positions. Each key references a Polygon Profile asset that defines one or more closed polygon outlines. Use it for stop lines, arrow markings, hatching, or any custom surface overlay that doesn’t fit the standard road marking system.

Keys use stepped evaluation — the last key at or before the current SOffset is active.

Property	Description
Profile	The Polygon Profile asset containing the polygon shapes
Alpha	Lateral position [0.1–1.0] within the lane width where the polygon anchor is placed: 0.1 = inner edge, 0.5 = lane center, 1.0 = outer edge

5.6. Curve Attributes

Curve Attributes are designed to generate any objects along road lanes, such as fences, barriers, trees, etc. There are 4 main types of the Curve Attributes:

• Curve Attribute - a base type from which you can inherit in C++ or BP and write any logic for generating objects along the road lane.

• Spline Mesh Attribute - designed to generate a USplineMeshComponent along a road lane

• Component Template Attribute - designed to generate any USceneComponent along a road lane

• Actor Template Attribute - designed to generate any AActor along a road lane

See Curve Profiles for details.