Vertex 3D Terrain Guide

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Make your first terrain

1. Open Tools → DPT Games → Vertex 3D Terrain.
2. Open Create Terrain and choose the type of terrain you want to create: Flat Terrain, Planet or Floating Island.
3. Choose Starting Biome, or Top Biome and Bottom Biome for a floating island. Adjust the terrain’s size, shape and resolution settings. The available controls depend on the selected terrain type. For example, a floating island lets you control its width, length, underside depth, plateau shape, underside shape and surface variation.
4. Choose where the terrain should be created using Spawn Position. If Live Preview is enabled, use the preview to check the overall scale and shape before generating it.
5. Click the generate button for the selected terrain type, such as Generate Floating Island, Generate Planetoid or Generate Surface.
6. The generated terrain can now be edited with the geometry and surface tools. Use whichever tools suit the result you want: sculpt or reshape the mesh, paint biomes, create paths, apply gradients, select faces with masks or combine compatible tools during the same stroke.
7. Start with broad changes to the overall form before adding smaller details. You can increase local geometry density later where finer editing is needed.
8. Save the terrain once you are happy with the result, along with the Unity scene and any generated assets you want to keep.

Targets, libraries and brush settings

Choose what you are editing

The active terrain supplies the current mesh and settings. For a terrain made from several objects, use the target list to choose which objects can be painted or sculpted. Active and enabled for Paint/Sculpt serve different purposes: selecting one tile does not necessarily enable every neighbouring tile for editing.

Add or register the terrain objects you need, refresh the list after changing your scene, and check the Paint/Sculpt switches before a stroke that crosses a boundary. A target should contain the mesh components used by the tool. A collider is also needed when you want physics raycasts to hit the terrain during gameplay.

Changing a pipeline changes how the terrain’s surface data is used. Save a copy before converting finished work, and compare its appearance afterwards. Texture detail from Terrain Atlas should not be expected to look identical in Direct Vertex Color.

For the individual presets, texture inputs and library actions, see the Biomes Guide. For controls that affect a whole material, see Terrain Material Settings. For biome-driven grass, flowers, mushrooms, pebbles and custom mesh placement, see the 3D Scatter Guide.

Generate a starting shape

Open Create Terrain, then choose Flat Terrain, Planet or Floating Island. Each generator creates a mesh with the terrain material and registers it as an editing target. Configure a suitable starting shape and biome before sculpting or painting details.

Placement, preview and biome selection

Live Preview displays a temporary, reduced-resolution grey mesh in Scene view. Use it to judge position, size and silhouette. The final terrain uses your selected full resolution; the grey preview is not a preview of the finished biome textures.

Starting Biome chooses the initial surface for flat terrain and planets. The picker follows your current surface pipeline and library. Floating islands use separate Top Biome and Bottom Biome choices, described below. You can repaint every generated surface afterwards.

Flat Terrain

Choose Shape Preset: Flat Plane, Island Mountain, River Valley or Crater Basin. Flat Terrain is the generator category; its height presets can still produce hills and depressions.

Click Generate Surface when ready. Choose enough geometry for the broad features you need, then add local detail later instead of starting every tile at maximum resolution.

Planet: continuous or tiled

Set Planetoid Name, Starting Biome, Radius and Mesh Structure. Single Mesh creates one continuous object; Multi Tile creates an arrangement across six cube faces.

For Multi Tile, Tile Size is calculated as (2 × Radius) / Tiles Per Face so the faces meet. High Density Borders doubles each tile edge’s density before projection, including cross-face seams and cube corners. Click Generate Planetoid, then inspect joins and use surface-oriented brushes when World Up would point the wrong way.

For an interior, generate a single-mesh Cube or Rounded Cube, select all its faces in Mask mode and use Invert Faces. This is an editing operation rather than a separate generator type.

Floating Island

The island is a closed mesh with a top plateau and sculpted underside. Set its name, placement and the two biome choices, then compare both sides in silhouette.

Click Generate Floating Island. Edge Radius changes geometry; Edge Blend Width changes the biome transition. Adjust them separately, then inspect the underside before painting or placing scatter.

Surface Variation

Enable Surface Variation for deterministic height variation on generated terrain, planetoids and floating-island tops. It is separate from the island’s underside Rock Jaggedness.

Use Live Preview to compare settings, then judge the full-resolution generated result. Strong variation on a coarse grid cannot produce fine detail, and adding noise is separate from painting surface textures.

Geometry and surface tools

The tool has separate geometry and surface choices. Some brush tools can work together, so you can shape and paint during the same stroke. Path, Mask and Gradient use their own editing workflows. Look at the active buttons and Scene HUD before dragging.

On/off controls are buttons: an enabled geometry control highlights green, while enabled controls elsewhere highlight blue; disabled controls are grey. Path controls use the same green highlight as the other geometry tools. Related actions share compact rows where space allows.

Geometry tools: change the mesh

Surface tools: change the appearance

With a multi-biome brush, select the surfaces you want and set their relative weights. Equalize Weights gives them equal influence. Noise can make the distribution less uniform. Try a small test patch before applying a complex mix across the entire terrain.

Dynamic topology and normals

Dynamic Topology adds geometry where an operation needs smaller triangles. Max Edge Length controls when an edge is considered too long: a lower value creates finer geometry and usually costs more processing and memory. It is used for cave/tunnel work and can be enabled for supported sculpting or painting workflows.

Use it when large triangles prevent the shape you want. It will not turn every coarse mesh into an evenly dense grid. Check the wireframe after a large change, and use a reasonable threshold for the scale of your scene.

The global Smooth / Sharp shading button sits beside Scene HUD. Sharp normals emphasise individual polygons; smooth normals soften lighting between them across the terrain mesh. This is separate from the Smooth brush, which moves vertices, and from a scatter variant’s Smoothing Angle.

Select faces and build a shape

1. Enable Mask and choose a selection method: Brush for a painted area, Single Face for precise picks, or Flood Island for a connected region.
2. Select the faces that form your intended footprint. Hold Shift to remove faces from the selection.
3. Use Grow, Shrink or Invert to refine it. Select Slope uses a range in degrees; Select Biome Faces uses the chosen surface ID.
4. Choose an operation or a shape preset. Check the affected region before applying it.
5. Inspect the result from the side as well as above. Undo and refine the footprint or settings if needed.

Selection and paint boundaries

Brush Drag selects a patch with a Circle or Square footprint; Single Face picks individual triangles; Flood Island selects a connected region. Shift removes faces. Grow and Shrink change the selection by one face ring, Invert selects its complement, and Clear removes the current selection. The counter shows selected faces across tiles.

For procedural selection, set Slope Angles and click Select Slope, or enter a biome ID and use Select Biome Faces. Select All is useful for whole-mesh operations such as face inversion.

Paint Edges applies to the Paint action and auto-painted generated shapes. Sharp keeps a crisp face boundary; Blended softens the surface transition across neighbouring faces. This setting controls the paint edge, while the saved Editing Mask controls where editing is allowed.

Shape, surface and topology actions

Limit editing to a saved area

1. Use the Mask tool to select the faces you want to edit.
2. Click Set Mask to save that selection as the editing area.
3. With Editing Mask enabled, paint and sculpt within that area. Faces outside it are protected. Shared boundary vertices stay fixed so neighbouring faces and welded tile seams are not pulled apart.
4. Toggle Editing Mask off to pause the restriction, then on to resume it. The default shortcut is Ctrl/Cmd + Shift + L; change it in the Hotkey Sheet.
5. Use Clear Editing Mask to remove the saved area. This keeps the current face selection.

The saved editing mask is separate from the current face selection. Growing, clearing or replacing that selection does not replace the saved area; use Set Mask again when you want a new boundary. A narrow selection may have few movable interior vertices because its shared boundary must remain fixed.

Clear an active editing mask before extrusion or hole filling. If an operation rebuilds faces while the mask is paused, the tool can clear that saved mask and display a notification. Select the new area and use Set Mask again after the topology change.

Turn a closed shape into an interior

Invert Faces reverses the selected triangles and their surface direction. To create a room from a cube-shaped planet, use Select All in Mask mode, then Invert Faces. Inspect it from inside and check the collider from the side your character will use. The operation supports Undo.

Invert changes which faces are selected; Invert Faces changes the mesh. Normal recalculation and supported subdivision, cleanup and LOD workflows preserve the chosen face orientation. A partially inverted closed surface can have adjacent faces pointing in opposite directions, so inspect the joins after reversing a local selection.

Place surfaces by height, slope or direction

Gradients turn a rule into a surface distribution. Choose your starting and ending biomes, or add ramp stops for several surfaces. The gradient’s position chooses the mixture; strength controls how firmly it is applied, and sharpness controls the transitions.

A cone’s slope/cliff filter can limit its application. Use Live Preview to position the rule before committing it, and reset the cone when starting on a very different feature. A biome’s own colour ramp is a separate control: it colours that biome’s texture detail, rather than setting a world-height snow line.

Roads, riverbeds, steps, tunnels and bridges

Begin with a surface path

1. Enable Path and choose Surface.
2. Add at least two nodes in Scene view. Move the handles to set the route; add nodes where the curve needs more control.
3. Choose Width, blending and a sculpt operation. Keep the first test short.
4. Choose Single Biome or a gradient along the route. Use Paint Path if you only need a surface strip.
5. Use Create Path for geometry, or Create & Paint when you want both the shape and the surface.

Make steps

Choose the Steps sculpt operation. Step Height is the vertical rise of each step. Step Depth controls its horizontal tread length along the path and can be set independently. Step Bevel controls the amount of edge rounding: low values give sharper edges; higher values give more worn or rounded edges.

Choose height and depth for the size of your character, then inspect the stairs from the side. A bevel should soften an edge without removing the flat tread you need. Add sufficient geometry for the intended spacing; a long stair run on very coarse terrain may need finer topology.

Paint the centre and banks

A path gradient changes the biome along the route. Stop position 0 is the start and 1 is the end. Add stops for sections such as dirt, gravel and rock. Bank controls place a separate biome toward the sides; bank width is a fraction of the half-width, rather than a distance in metres. For example, 0.35 uses the outer 35% of each side’s half-width.

The preview helps show where neighbouring surfaces share influence. Use it to check the banks and transitions before painting. A painted river biome gives you a river-looking strip; carve a bed separately if you need actual channel geometry.

Create a tunnel

Switch to Tunnel and position the route through the terrain. Choose Circle, Square or Flat Bottom Arch for the cross-section. A flat bottom is useful when the tunnel should have a walking surface.

Minimum cover depth is the amount of solid terrain required above the tunnel. A route can be invalid even if its centre is underground, because its full width or height breaks through the outside. Check red or invalid preview regions, move the route deeper, reduce its size, or adjust the cover requirement to suit the intended opening.

Create Tunnel changes geometry; Paint Tunnel changes the wall surfaces. Inspect the entrance, exit and any tile boundaries after creating it.

Create a bridge

Switch to Bridge. Put the ends on the landmasses you want to connect and use intermediate nodes across the gap. Flat Deck makes a simpler deck; Deep Girder gives a deeper structural profile; Arched Underside adds an arch below a flat walking top.

Inspect the bridge from above and below, particularly where it joins each landmass. On a curved world, check that the full span clears the terrain instead of assuming world-up placement will suit every side of the planet.

Choose precise endpoints when needed

Automatic endpoint placement is the default for tunnels and bridges. If you need a specific opening or join, use Pick Start or Pick End to select an endpoint face or connected face patch. Each end is independent, so you can pin only the start, only the end, or both.

Select a connected patch on the relevant terrain object whose boundary matches the opening you want. A square or rectangular patch is useful for a deliberate square end. Clear an endpoint selection to return that end to automatic placement. After deleting or rebuilding faces near a pinned endpoint, check the selection and repick it if the topology has changed.

Work across terrain tiles

Tiles divide a larger terrain into separate mesh objects. The tool’s neighbour and seam handling lets supported edits operate across their shared boundaries, but the objects still need to be registered and enabled for the operation.

1. Use a generated tile arrangement or check that the intended borders meet.
2. Register the tiles in the target list and confirm the Paint/Sculpt switches.
3. Test a small stroke across one seam. Inspect both the geometry and the surface transition.
4. For a path, tunnel or generated feature crossing tiles, inspect every affected join after applying it.
5. Save all affected tile meshes, rather than only the active tile.

A material’s Seam Blend setting blends texture projections. It does not weld mesh borders or repair a hole. If a seam looks wrong, first decide whether you are seeing a physical gap, mismatched lighting normals or a texture transition; those need different adjustments. Arbitrarily overlapping meshes should not be assumed to form a joined terrain.

Save and optimise your terrain

Keep editing manageable

Build the broad shape before using fine topology. Use smaller brushes for detail, and avoid a very small Max Edge Length across a large area unless you need the extra triangles. Geometry density affects editing cost; texture resolution affects surface memory and quality. Reducing one does not automatically fix the other.

Compatible geometry and surface tools share brush data during a combined stroke. Moving vertices keeps reusable paint buffers, while topology changes, changed seam data and Undo/Redo refresh the affected caches. This happens automatically and needs no extra setting. It reduces repeated preparation; the cost of sculpting, topology and scatter rebuilds still depends on your terrain and brush.

Bake ambient occlusion in Direct Vertex Color

The raycast AO baker adds shading for crevices and contact areas in the Direct Vertex Color workflow. It is not a lightmap and does not replace scene lighting. Bake after the main shape is finished; later geometry edits can make the stored shading out of date.

Ray quality trades bake time for sampling quality. Maximum shadow distance controls how far nearby geometry can influence the shading. Contrast controls how pronounced the result looks. Start with a test bake and avoid crushing every sheltered area to black.

Partition and generate LODs

Chunking divides the terrain into a grid, with options such as 1×1, 2×2, 4×4 and 8×8. Smaller chunks can help Unity show only the relevant parts, but they create more objects and rendering groups. Choose a layout that suits your scene rather than always using the largest grid.

LOD1 and LOD2 are simplified meshes. Their target ratios describe how much geometry to retain: a smaller ratio means fewer triangles and a greater chance of losing small shapes. Unity’s transition thresholds use relative screen height, not a distance in metres. The final culling threshold determines when a group stops being drawn.

The generated collider uses LOD2. Check that stairs, edges and openings still collide as intended. If you use triangle-based surface queries, the surface data must correspond to the collider’s actual mesh and triangle order; data baked for a different mesh can return the wrong surface.

Use Hide Original Mesh when appropriate for the generated result, and check that you are not displaying both versions. Treat chunking and LOD generation as a finishing workflow; it does not automatically make every edit to the original terrain faster.

Save the right assets

Material changes affect every object using that material. Duplicating a GameObject alone does not necessarily give it independent assets. Save a separate material or use the standalone workflow when two terrain pieces need different global settings.

Keyboard and mouse reference

The keyboard bindings below are defaults. Use shortcuts while working in Scene view. Context matters: the same key can have a different action in Mask, Path, Gradient or Dusting mode. Typing in an editable field takes precedence. On macOS, Cmd serves the Ctrl/Cmd bindings.

• [ / ] and Shift + mouse wheel adjust brush radius. Ctrl/Cmd + Shift + PageUp / PageDown make fine radius changes.
• Ctrl/Cmd + Shift + Up / Down adjust geometry rate; Ctrl/Cmd + Shift + Left / Right adjust surface opacity. The minus/equal bindings act on the current tool context.
• Ctrl + drag reverses supported sculpt/inflate strokes. Shift temporarily smooths or blends supported brush strokes and subtracts during mask selection.
• Alt + Shift + 1…9, 0 selects a biome within the visible palette group. Tab / Shift + Tab changes palette groups.
• Escape leaves the current special interaction or deactivates the tool; leaving a path mode keeps its nodes. Use Clear Nodes when you actually want to remove the route.

Change shortcuts in the Hotkey Sheet

1. Open Hotkey Sheet in the terrain window. Search by action or key, or expand a group such as Tools, Brush adjustments, Mask mode or Path mode.
2. Click the action’s key button, then press a new key combination. Modifier keys alone wait for the main key. Escape cancels recording.
3. Use × to clear a binding, Reset to restore one action, or Restore Defaults to reset the whole list.

Changes save automatically for your Unity editor user and are shared across projects. Tooltips and the Scene HUD show the current configured keys. If a key conflicts with another action in an overlapping context, the sheet names that action and refuses the assignment. Change or clear the other binding first. Mask, Path and Gradient may reuse a key when their contexts do not overlap; general actions apply across modes.

Mouse gestures and Unity Undo/Redo stay fixed: Shift + mouse wheel adjusts radius; Shift + drag temporarily smooths/blends or subtracts selected faces; Ctrl + drag lowers/deflates; Ctrl + click samples a biome in Paint; Shift + click constrains path nodes to X/Z. Use Ctrl/Cmd + Z for Undo, Ctrl/Cmd + Shift + Z or Ctrl/Cmd + Y for Redo. Typing into an editable field still takes precedence outside shortcut recording.

Terms used in these guides

When the result is not what you expected

Support

If you need help, describe the result you expected, the control you used, and what appeared instead. Include your Unity version, the selected surface pipeline, and a screenshot of the relevant settings. For a runtime query problem, also include the collider type and when you last baked surface data.

Use the DPT Games contact form or join the DPT Games Discord.

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