MAG Spline Placer Pro

Spline Placer Pro is a professional Unity Editor tool designed for fast, flexible and highly customizable object placement along splines and inside closed areas.

Optimized for mobile games and all platforms, it provides a powerful, non-destructive workflow for level designers and environment artists.

It allows you to instantly populate roadsides, fences, vegetation, forests, rocks, poles, props, walls and decorative elements with full artistic control and high performance.

Built for workflow speed, precision and creative freedom, Spline Placer Pro drastically reduces manual placement time and eliminates repetitive work — all fully editor-based with zero runtime overhead.

 Key Features

Advanced Spline Placement

• Create and edit splines directly in the Scene view

• Smooth Catmull-Rom interpolation with adjustable samples per segment

• Visual spline curve & point handles

• Resume editing at any time – splines are never destroyed

Multiple Placement Sets

• Unlimited Placement Sets per spline

• Each set has independent settings

• Enable / disable sets individually

• Perfect for layering different object types on the same spline

Prefab Management

• Add one or multiple prefabs per set

• Automatic random prefab selection when multiple prefabs are used

• Quick remove (X button)

• Ideal for natural variation and visual diversity

Precise Placement Control

• Override spacing per set

• Random spacing (min / max)

• Lateral offset & vertical offset

• Random lateral & vertical offsets for organic results

• Perfect for trees, roadside props, poles and vegetation

Rotation, Scale & Jitter

• Align objects to spline tangent

• Project to surface with raycasting

• Use surface normal up (terrain-aware placement)

• Random yaw (rotation)

• Fixed yaw override

• Position jitter

• Random scale or fixed scale per set

Double-Sided Placement

• Place objects on both sides of the spline

• Adjustable side separation distance

• Ideal for roads, fences, walls and barriers

Fence & Continuous Objects Support

• Align to tangent for perfect fence placement

• Disable unnecessary rotation options for straight, clean results

• Designed for walls, fences, rails and barriers

Area Fill Mode (Major Feature)

• Convert any closed spline into an area

• Fill the interior with objects (trees, rocks, props, grass, forests)

• Set Area Density (objects per 100m²)

• Minimum separation between objects

• Natural random distribution – no grid look

• Each set switches automatically to Area Fill specific settings

Procedural Mesh Generation

• Generate a single combined mesh from spline objects

• Optional Mesh Collider generation

• Destroy original instances after merge (clean hierarchy)

• Ideal for fences, walls and optimized static geometry

Collision-Safe Placement

• Avoid overlapping with existing geometry

• Avoid placement on selected layers (roads, buildings, etc.)

• Adjustable avoid radius

• Perfect for complex scenes and production-safe placement

Terrain Conform System (Bake)

• Conform spline and objects to terrain height

• Adjustable conform step

• Insert objects between spline points

• Optional Flatten Y (Keep XZ) for straight placements

Smart Preview & Validation

• Auto Generate (Live Preview) or manual generation

• Debounce system for editor performance

• Clear validation messages before generation

• No broken setups or silent errors

Clean Hierarchy & Organization

• Automatic parent container creation

• Custom group name prefix

• Optional static flags, shadow & probe settings

• Clean, production-ready hierarchy

Performance Focused

• Fully editor-based tool

• Zero runtime cost

• Optimized for mobile & large scenes

• No unnecessary gizmo overhead

 Perfect For

• Roadside decoration

• Fence & barrier generation

• Vegetation & forest creation

• Environment detailing

• Open-world building

• Simulation & driving games

• Level design workflows

• Procedural world creation

Typical Workflow

1. Select or create a spline
2. Press Create New and place points (Shift + Left Click)
3. Add one or more Placement Sets
4. Add prefabs
5. Adjust spacing, offsets, rotation & randomness
6. Enable Area Fill Mode if needed
7. Preview or Auto Generate
8. Generate instantly

Included

• Full source code

• Editor tool

• AAA+ Documentation PDF

• Example setups

🛠 Supported Unity Versions

Unity 2021 LTS and newer