Terrain Editor¶

The Terrain Editor is the authoring window for entities with a Terrain component. It paints the terrain's maps — heightmap, blend maps, and foliage density maps — and places props on the surface, all with the same brush.

Opening the window¶

Select the terrain entity and click Open Terrain Editor in the Properties window, or choose View → Terrain Editor. The window can also stay open while you work: it follows the selection, and shows a hint instead of the tools when the selected entity is not a terrain or a scene is playing.

Terrain editing is disabled during play mode.

Maps¶

Every brush writes into a texture, and each map section has the same row:

Painted maps are written as PNG files under terrain_maps/ inside the project's assets directory, so they are referenced, exported, and version-controlled like any other texture. Heightmaps are stored 16-bit to keep gentle slopes free of terracing.

Files are written in the background while you paint, and every scene save flushes the pending writes and deletes the maps no scene, bundle, or material still references. If a write fails the editor says so and keeps the scene marked unsaved, so the next save retries it.

Sculpt¶

Sculpt brushes write the heightmap. They need a heightmap to exist first — the buttons stay disabled until one is created.

Flatten takes its target from Sample height (picked from the terrain where each stroke begins) or from an explicit Flatten height. Noise exposes a Noise size — the width of one noise feature in world units, anchored to the terrain so the field stays put as the brush moves. Terrace exposes Terrace steps, the number of flat levels the height range is cut into.

Texture Paint¶

The terrain's ground is a base texture plus up to nine detail layers. Layers are grouped in threes: each group is weighted by the RGB channels of one blend map, and the Blendmap row above the list creates the map for the group the selected layer belongs to.

Painting is a blend-map write, so the layer textures themselves are never modified.

See Detail layers for how the layers are blended at runtime.

Layer settings¶

The arrow beside a layer's clear button opens its settings under the row. A layer with Enable PBR off shows only what it can use — the rest appears once it is on, and the layer's preview is marked PBR in the list.

Copying a material takes its base color and tint, normal, metallic/roughness, occlusion and factors, and turns the layer into a PBR one. Emission and transparency are not part of a terrain layer and are left out; the layer keeps the tiling it already had.

Slope and height mask¶

While a paint brush is selected the Brush section grows a Mask toggle that restricts painting to a range of ground slope (degrees) and height (normalized against the terrain's max height). Texels outside the range keep what they had — the way to paint "rock only above 40 degrees" without tracing the cliffs by hand.

Foliage¶

A foliage layer scatters a mesh over the terrain from a painted density map. Instances are resolved from that map at runtime rather than stored in the scene, so a dense field costs a density map and a set of parameters.

Add a layer, pick its mesh (a model file), create its Density map, then paint with Paint density (Ctrl erases) or Erase density (Ctrl paints).

Foliage entities are created by the engine, not authored: they never appear in the Structure panel, and clicking one in the viewport selects its terrain.

Objects¶

The Objects section places real props — models or entity bundles — along the drag, as children of the terrain entity.

Place objects scatters within the brush radius (Ctrl erases); Erase objects removes the terrain's child props under the brush (Ctrl places). Only meshes and bundle roots count as props — a light or a camera parented to the terrain is neither erased nor counted for spacing.

Instanced placement keeps one host entity per asset under the terrain and adds an instance per object. Instances can be moved, but carry no components of their own, so turn Instanced off for props that need collision, scripts, or animation. Bundles are hierarchies of entities and are always placed un-instanced.

A whole drag is one undo step, whichever mode it used.

Brush settings¶

Because strength is a flow rate, holding the brush in place keeps building up the effect, and stroke speed does not change how much a slow frame applies.

Brush settings, the selected brush, map resolutions and the placement palette are stored per project, so they come back the way you left them.

Shortcuts¶

Undo¶

Each stroke is one undo entry. Map strokes record only the rectangle of texels they changed rather than a copy of the whole map, so a long sculpting session stays cheap to undo.

See also¶

• Terrain — terrain concepts, LOD tuning, and the runtime API
• Terrain class reference
• Properties & Components — the Terrain component rows