Splines are defined lines that define where long, linear groups of assets or textures will be placed.
Common uses for using a spline would include creating a road, pathway, row of trees, fence, or wall.
A single spline can have multiple components attached to it, such as a road that includes a wide dusty path with narrow wagon ruts and a line of bushes along each side.
Adding a Spline
To add a Spline to a map, select a Spline in the Object Browser and drag it onto the Render View.
The spline will appear where you placed it, allowing you manipulate it and add assets to it.
There are a number of different types of splines, each with a specific use.
Any Spline variation can be added using the method described above, including
- Standard Spline
- Slotted Spline
- Strip Component
- Wall Component.
The spline, referred to simply as a Spline, is the foundation most splines are built upon.
This form of spline allows you to to add components, textures, objects, deformation and other elements along it to create a variety of effects.
Normal splines possess two main modes, Object Mode and Edit Mode.
When you have a spline selected, pressing SPACE BAR will toggle between these two modes
This mode allows you to rotate the spline as a a single object, allowing you to orient it as needed.
This mode allows you to edit the individual control points of the spline.
In the Scenario Tree, a normal spline and it's points will appear with its name and four coordinates, as shown in the example below.
These coordinates denote the exact location of the points of the spline.
Spline Control Points
By default, a new spline will be created with four Control Points, which dictate the path of the spline.
To move a Control Point, Left-Click on it to expose the Interaction Icon.
Then, Left-Click on the Interaction Icon to move the control point to a new location.
To create a new Control Point, Left-Click one of the existing control points and Right-Click on the terrain at your target location.
A new control point will be created at that target location, connected to the previously-selected control point.
By adding more Control Points from an end Control Point of a Spline, you can continue to extend the spline in any direction you wish.
Splines have a number of unique properties that appear in the Properties window when a spline is selected, as detailed below.
These properties will appear in both Object Mode and Edit Mode.
- Comment: Allows you to add a to your spline. Visible to anyone working in the editor.
- Display Name: A custom name you can add to this spline for easy tracking/finding in the Scenario Tree.
- Locked: If checked, the spline cannot be edited.
- Visible: If not checked, the spline will not be visible in the editor.
- Seed: Changes the random variations added to a transform component.
This will mainly be noticeable when there are objects in the instance component.
- Height: How different terrain elevations will blend between the two control points. Height when used in combination with the deform component, will determine the height of the point. Height when used with instance component will move objects to the set height.
- Position: How the spline will blend between two points. This allows you to edit the position of the spline within the world.
- Width: How different widths will blend between the two control points. Width will overwrite the overall width of the strip component and apply the set width to that point, allowing you to create precise variety on some paths.
Within the options for each Spline parameter there are three settings: BSpline,. CatRom, and Linear, which dicate the behaviour of the spline.
These settings are accessed through the Properties panel, and detailed below.
This is the most commonly used setting, and creates a spline with softer curves.
The spline will be harder and ignore the last two control points to create sharper turns.
Will create a straight spline with hard angle turns.
Components can be added to a spline to add textures, objects, deformation, and other elements along a spline.
Any added spline component can be copied into another spline, and or combined with other components.
To add a Component to a Spline, Right-Click on the Spline in the Scenario Tree and click Add from the Add Blueprint menu.
There are seven possible Spline component types to choose from.
Deform Components allow you to raise or lower the terrain along the spline, creating ditches, rivers, ridges, and similar terrain elements.
Instance Components allow you to add objects along the spline, such as trees, rocks, bushes, or sheep.
Strip Components allow you to add a ground texture to the spline, creating a dirt, gravel, mud, or similar effect along the spline.