Tutorials

Welcome to Cave Builder by Arkerion Studios.

This manual teaches the tool by doing. Each tutorial builds a real cave from start to finish, one click at a time. You don’t need to read it all: start with Tutorial 1, then pick the tutorials you need. Every setting is explained in detail in the Cave Builder - Documentation.

Before You Start

• Open the tool:Tools > Arkerion > Cave Builder. Dock the window next to the Inspector, so you see the window and the Scene view at the same time.
• The Step Guide: the panel in the bottom left of the Scene view always says what to do next and has a button for it. Leave it on while you learn.
• Undo: every action is one Undo step (Ctrl+Z). Experiment freely.
• Save often: the cave is saved with your scene. Save Layout (Finish tab) also saves the design as a file before big experiments.

Three things to know before you click:

• You place points on the walking floor, in the middle of the passage. The cave is built around them.
• The cave updates by itself after every change.
• The finished cave is baked into an ordinary prefab for your game. The editable cave stays in your scene.

Tutorial 1: Your First Cave (15 minutes)

You build a short cave with an entrance, a climbing passage, a room, a side branch and a closed end, then walk through it and bake it.

Step 1 - Create the cave

1. Open a new, empty scene (File > New Scene).
2. In the Cave Builder window, open the Build tab and click Create Cave. A cave object appears in the Hierarchy and is selected.
3. Under Point Placement, choose Draw on Plane and leave Plane Elevation at 0. An empty scene has no ground to click on, so points land on this flat plane.

Step 2 - Place the entrance

1. Click Place Entrance.
2. Click in the Scene view where the cave mouth should be. A ghost of the entrance appears.
3. Move the mouse: the green ghost tunnel shows where the passage goes into the ground. Click again to confirm the direction.

Drawing of the first passage starts right away.

Step 3 - Draw the passage

1. Click a point about 10 m in front of the entrance, a little to one side.
2. Click three or four more points in a gentle curve, about 10 m apart. The dotted line from your last point shows the distance and the slope.
3. Press Enter to finish.

You now have a passage. Blue lines show its walking floor; white spheres are its points.

Step 4 - Make it climb

1. Click the third point to select it.
2. Drag the green (up) arrow of its move handle upwards by about 3 m. The passage rises towards it and falls again behind it.
3. Drag the yellow cube on its side outwards: the passage gets wider at this point. Sizes blend smoothly between points.

If the slope gets too steep to walk, a warning appears. Spread the height over more points, or select the passage and click Fix Path.

Step 5 - Add a room

1. Click the passage line (not a point) to select the passage.
2. On the Build tab, set Room Shape to Round, Room Template to 3 Connections and Size to Medium.
3. Click Insert Room, move the mouse over the middle of the passage and click when the ghost is green.

The room cuts into the passage; both halves stay connected to it. Select the room to see its bar in the Scene view: Smaller / Larger, Square / Round, and a rotation slider. Press E (Unity’s Rotate tool) for a rotation ring, W to move it.

Step 6 - Branch off

1. The room has an unused opening, shown as an orange arrow. Click it.
2. On the Selected tab, click Draw Branch.
3. Click three points away from the room and press Enter.

Step 7 - Close the end

1. Select the branch you just drew.
2. On the Selected tab, under Ends, click Close on its free end. A rounded rock cap seals it.

Free openings of rooms never need closing: they are plugged automatically.

Step 8 - Check for problems

Look at the status bar at the bottom of the window. If it shows warnings or errors, open the Finish tab, find Validation and click Show next to a message to see where it is. Many problems have a one-click Fix button.

Step 9 - Give it a look

1. Open the Appearance tab and click the Desert theme. Only the materials change; the layout stays.
2. Under Distortion, set Strength to 1 and Size to 16. The whole cave bends so it looks natural, without gaps.
3. Under Decorations, tick Generate Decorations.

Step 10 - Walk through it

1. On the Finish tab, click Play Test.
2. Click into the Game view, then walk with WASD, look with the mouse, run with Shift, toggle the lantern with L.
3. Leave Play mode when you are done. Nothing from the test stays in your scene.

Step 11 - Bake it

1. On the Finish tab, under Bake, enter a Prefab Name, for example MyFirstCave.
2. Click Bake Cave.

The prefab and its meshes are saved in the output folder. Drag the prefab into any scene; it needs no Cave Builder code. Changed the cave later? Update Existing Bake updates every copy of the prefab.

Congratulations: that is the whole workflow. The next tutorials go deeper.

Tutorial 2: A Cave Inside a Hill

You build a cave that opens in the side of a terrain hill and runs underground.

1. Create a Unity Terrain and raise a hill with the terrain tools.
2. In the Cave Builder window, click Create Cave.
3. Under Point Placement, choose Draw on Surface and set Depth Below Surface to about 6 m. Entrances sit on the terrain; everything else stays this far underground.
4. Click Place Entrance and click at the foot of the hill, aiming into the hill.
5. Draw the passage across the hill by clicking on the terrain. The points go 6 m below where you click, and the passage descends gently from the entrance to that depth.
6. Press Enter, then on the Finish tab under Export & Tools > Terrain click Cut Terrain Opening. The terrain opens at the cave mouth.
7. Walk in with Play Test.

Tips:

• Built a cave that is too shallow? Lower Existing Cave (Build tab, Point Placement) moves it down in one step; the entrances stay.
• Hide the terrain edge around the mouth with rocks or the manual kit pieces from Prefabs/CaveBuilder Basic.

Tutorial 3: A Labyrinth

For dungeon-style caves, place the important places first and join them afterwards.

Place the key places

1. Click Create Cave, then Place Entrance and click twice (position, then direction). Press Esc to stop drawing.
2. Click Place Room, click the room centre, aim its Entry and click. Place four or five rooms spread over about 80 x 80 m. Mix shapes: round rooms with 5-8 connections make great hubs.

Join them

1. Open Connections on the Build tab and click Connect (A → B). Every free opening becomes a big target.
2. Click an opening, then another. A passage joins them. The mode stays on: keep clicking pairs.
3. Or click Auto Connect to join openings that face each other, then add the missing links by hand.
4. Press Esc twice to leave the mode.

Add crossroads and side tunnels

• Cross passages: draw a passage across another one at about the same height. When you finish, the two are joined by a 4-way crossing (Auto Crossroads is on by default).
• Branch from a passage: select a point in the middle of a passage. In its bar, click Branch Left or Branch Right, then draw the new tunnel.
• Join while drawing: while drawing, click on another passage to end yours there with a 3-way crossing.
• Fix the angle: select a crossing and click Angle ▾ > Fit to Passages: it turns so its openings point where the passages go.

Shape the tunnels

Select a passage: green + markers appear in the middle of each section. Click one to add a point there, then drag it to bend, climb or descend the tunnel.

Finish with Validation (Finish tab) and a Play Test through every route.

Tutorial 4: Make It Look Great

Everything here is on the Appearance tab. None of it moves the layout.

Theme and rock look

• Theme: Basic, Desert, Ice, Jungle or Lava. Decorations always match the theme.
• Rock Look > Rock Variation: more or fewer patches of the alternative rock texture on walls and floors.
• Rock Look > Shape Irregularity: smooth bulges in the walls.
• Texture Scale: bigger or smaller rock patterns.

Distortion

Bends the finished cave so it never looks machine-made. Good start: Strength 1, Size 12-20 m, Vertical 0.3. Larger Size gives long, slow bends. Check the Validation list afterwards for clearance warnings.

Decorations

Tick Generate Decorations, then:

• Density - how many pieces, from a few to really dense.
• Size - all pieces bigger or smaller.
• Size Variation - how different their sizes are. 0.5 or more looks natural.
• Turn Variation / Tilt - different directions and a slight lean, so no two look alike.
• Clusters - groups them like real caves: little stalagmites next to big ones, rocks around boulders.

A good natural look: Density 0.4, Size Variation 0.5, Tilt 8°, Clusters 0.5.

Lights

Tick Place Lights. Warm colours feel like torches; cold blue feels like ice or magic. Keep Shadows on None for most lights; shadows are expensive. Use brighter, warmer light on the main route to guide the player.

Wetness (every theme except Lava)

Click Damp, Wet or Dripping for a quick look, or turn on Custom Wetness for wet walls, water streaks and puddles in this cave only.

Tutorial 5: A Lava Cave

1. On the Appearance tab, click the Lava theme. The Lava section appears; lava caves are never wet, so the Wetness section disappears.
2. Open Lava and turn on Custom Lava, so the settings apply to this cave.
3. Open Heat Zones:

• Hot Floor - how much of the floor is glowing liquid lava.
• Warm Spread - how far the warm lava reaches up the walls around it.
• Hot Leaks - glowing lava running down the walls.
• Warm Patches - lava streams in the cold rock.

1. Open Lava Leaks and raise Leaks for flowing, animated lava coming out of the walls.
2. Under Lights, pick a warm orange Colour. Orange light makes the glow believable.

Flowing lava moves in Play mode, or in the Scene view with Always Refresh on.

Tutorial 6: From Editor to Game

Final checks

• Validation must show no errors; errors block baking.
• Preview > Preview Quality: Final shows exactly what will be baked.
• Play Test every route once.

Bake

1. Finish tab > Bake: set Output Folder and Prefab Name.
2. Leave Colliders, LOD1, Lightmap UVs and Mark Static on.
3. Choose whether to include Decorations, Lights and the Path.
4. Click Bake Cave.

Place the prefab in your game scene. Keep the editable cave in a separate work scene, or disable its object next to the prefab.

Extras for your game

• Export Path - waypoints along every passage, for AI patrols, camera rails or spawn points.
• Export Minimap - a top-down image of the cave for your map screen.
• Occlusion Culling (Window > Rendering > Occlusion Culling) - caves hide almost everything behind the next bend, so baking occlusion culling makes them very cheap to render.
• Low Quality on the theme material - a lighter shader option for mobile and VR.

Quick Answers

• I click and nothing happens. Select the cave first, and make sure the mouse is over ground (Draw on Surface) or switch to Draw on Plane.
• The walls fold or pinch. The bend is too tight: select the passage and click Fix Path, or move points apart.
• The player falls through. Leave Colliders on (preview and bake).
• The cave is dark. Turn on Place Lights, or add your own lights.
• I want to change one room only. Select it: change size, shape and rotation in its bar. Connected passages follow.

For everything else, see Troubleshooting in the Cave Builder - Documentation.