Before starting this tutorial, read:
- Working with Data — Groups, Resource Types, and Prototypes
- Working with MegaWorld Window — how to navigate the window
Step 1 — Open the MegaWorld Window and select Spray Brush
Press Alt + Z to open the MegaWorld Window. In the Tools Panel, click the + button and choose Spray Brush.Step 2 — Add a group and prototypes
In the Selection Panel, click Add Type and choose Terrain Object or Unity/GameObject. Inside the group, click Add Resource and add the prefabs you want to place.Spray Brush does not support Unity/Terrain Detail or terrain textures. Use Advanced Brush for those resource types.
Step 3 — Set brush size and spacing
In the Settings Panel:- Brush Size — the diameter of the area within which each random placement point is chosen. Use Shift + Scroll Wheel in the Scene View to adjust quickly.
- Spacing — how far the cursor must move before the tool fires another placement attempt. Lower values place more objects per drag stroke.
Step 4 — Optionally configure filters and overlap checking
Each group has a Simple Filter Settings section. Enable Check Height or Check Slope to restrict placement to terrain within a height or slope range. Placement attempts that fall outside the filter return zero fitness and are skipped. Each prototype has an Overlap Check Settings section. This prevents new objects from being placed too close to existing ones.Step 5 — Paint in the Scene View
Move your cursor into the Scene View and click or drag. On each stroke tick the tool picks one random offset within the brush, raycasts to the surface, evaluates the filter, selects a prototype by weighted success, applies the transform stack, runs the overlap check, and places the object if all steps pass.What’s next
- Use Brush Erase to remove overpainted objects.
- Use Brush Modify to adjust scale or rotation on already-placed objects.
- Read the full Spray Brush reference documentation.