Terrain Splines
RustEdit ProA terrain spline changes the terrain along its line or inside it: it flattens a bed for a road, raises a ridge, cuts a canyon, levels an area or paints it. The change stays live. Move a knot and the terrain follows; delete the spline and the change goes away.
Before you start
- You need RustEdit Pro. Without it, the terrain types are greyed out in the type dropdown, their settings cannot be changed, and terrain splines in a scene do not change the terrain.
- Know how to draw and edit splines. See Editing splines.
How to shape the terrain with a spline
- Make a spline entity and draw the line. For an area, close the spline.
- Turn on spline edit mode and set Spline Component to Terrain Spline.
- Under Paths, open the spline's row and pick a Type: Road Bed, Ridge / Canyon, Shape Area or Paint Area. The terrain changes at once.
- Set the options. The line under the type says what the type does.
- Move knots to adjust the shape. The terrain is built again after each change.
One spline entity can have several terrain splines, each with its own type.
The types
| Type | What it does | Starts with |
|---|---|---|
| Road Bed | The ground along the line goes to the line's height. Move the knots up or down to shape it. | Width 12, Falloff 15 |
| Ridge / Canyon | Raises the ground along the line by the amount, or lowers it with a negative amount. The profile shapes it from the middle to the edge. | Width 80, Falloff 20, Amount 20 |
| Shape Area | The ground inside the closed line goes level, at the line's average height plus the level. | Falloff 20 |
| Paint Area | Paints the inside of the closed line. | Falloff 5, Splat Dirt |
Options
The rows depend on the type.
| Option | Types | What it does |
|---|---|---|
| Width | Road Bed, Ridge / Canyon | The full width of the line in meters. |
| Falloff | All | How far past the edge the change eases out, in meters. |
| Offset | Road Bed | Meters over (or under) the line the ground goes to. |
| Amount | Ridge / Canyon | Meters the ground is raised in the middle. Negative lowers it. |
| Level | Shape Area | Meters over (or under) the line's average height the inside goes to. |
| Opacity | All | How much of the change is made, 0 to 1. |
| Profile | Ridge / Canyon | The shape across the line, from its middle (left) to its edge (right). |
| Splat | All | The ground texture painted along the line or inside the area. None paints no splat. |
| Biome | All | The biome painted along the line or inside the area: Arid, Temperate, Tundra or Arctic. |
| Topology | All | The topology added along the line or inside the area. |
The default profile is full at the middle and eases to nothing at the edge. Edit the curve for a flat top, a steep wall or a V shape.
How it works with other terrain changes
- Terrain splines are applied after your terrain edits and the terrain changes of placed prefabs. Where a terrain spline works at full strength, it decides the result.
- The spline's knots set the height. Hold Ctrl while you drag a knot to put it on the current ground.
- When you export the map, the exported terrain includes the changes of every terrain spline.
- The terrain splines themselves are saved in the scene, and in RustEdit's data in the map, so they stay editable.
To go on working, open the scene file, not the exported map. The exported map's terrain already has the terrain splines' changes, and when you open the map, its terrain splines make them a second time. A Ridge / Canyon is raised or lowered twice. The other types change the ground again in their Falloff and wherever Opacity is under 1. If you have only the map, delete its terrain splines after you open it: their changes stay in the terrain, but you can no longer edit them.
A Road path does not change the terrain. Draw a Road Bed along the road, in a second spline entity with the Terrain Spline component, to give the road a smooth bed.
Undo
Changes to the knots are undo steps, and the terrain follows the undo. Changes to the type and the options rows are not undo steps.
Use your splines in a terrain graph
The terrain graph's Spline Mask node turns the map's splines into a mask and a height. It can take all splines, one Rust path type, the terrain splines, the prefab splines, or the splines without a type. See Terrain graph nodes.