Spline Asset Placer

Spline Asset Placer

Module: Art · Category: Scatter · Tool ID: SplineAssetPlacer

Artist-friendly spline-driven mesh distribution. Pick a spline actor in the level, pick a mesh, set spacing, click Place. Includes tangent alignment, ground snap with surface-normal alignment, scale randomization (uniform or per-axis), random rotation, lateral/vertical offset, quick presets (Road / Fence / Pipe / Foliage Row / Streetlight), and batch mode for applying the same setup to all spline actors in the level.

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When to use it

• Distributing repeating meshes along a path: roads, fences, pipes, cables, streetlights, foliage rows
• Quick rope bridge / chain link / row-of-anything authoring
• Ground-snapped foliage rows that follow terrain
• Batch placement on multiple splines at once

When not to use it

• Don’t use this for irregular scatter — use Procedural Scattering & Placement Suite for that
• Don’t expect cubic interpolation between samples — placement uses spline distance, snapped to spacing

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Opening the tool

1. Open the EQLabs Hub and search for Spline (or browse to Art → Scatter)
2. Click the tool card
3. Either: select a spline actor in the level and click Pick Selected Spline Actor, or click Create Spline Actor to spawn one

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Interface tour

The panel is organized into six sections:

1. Source

Field	What it does
Spline Actor	Currently picked spline actor (selected from the level)
Pick Selected Spline Actor	Picks whatever spline-bearing actor is selected in the level
Create Spline Actor	Spawns a new actor with a USplineComponent
Mesh picker	The static mesh to distribute

2. Placement

Field	What it does	Default
Spacing	Distance between instances along the spline	200 cm
Spacing Jitter	Random ± variation on spacing	0
Start Trim / End Trim	Skip the first/last N units of spline	0
Offset Right	Lateral offset from spline	0
Offset Up	Vertical offset	0
Random Offset Right / Up / Forward	Random ± jitter on each offset axis	0
Scale Min / Max	Uniform random scale range	0.9 – 1.1
Non-Uniform Scale	Toggle X/Y/Z independent randomization	false
Per-axis scale ranges	When non-uniform, separate min/max per axis	each 0.9 – 1.1
Align to Tangent	Rotate instance to follow spline direction	true
Random Yaw	Random Yaw rotation	false
Yaw Min / Max	Random Yaw range when enabled	0 – 360
Pitch / Roll Min / Max	Random Pitch/Roll ranges	0
Step Rotation Yaw	Incremental Yaw per instance (spiral stairs, twisted cables)	0

3. Ground Snap

Field	What it does	Default
Ground Snap	Trace from the spline location to ground and snap	false
Ground Trace Distance	How far to trace down	500 cm
Align to Surface Normal	Rotate instance up-vector to ground normal	false
Sink Depth	Push the instance into the ground (cm)	0

4. Quick Presets

Per-row preset list:

Preset	Tuned for
Road	Wide spacing, tangent-aligned, no jitter
Fence	Tight spacing, tangent-aligned, slight scale variation
Pipe	Tight spacing, tangent-aligned, locked rotation
Foliage Row	Variable spacing + jitter, ground-snapped, random Yaw
Streetlight	Wide spacing, tangent-aligned, no scale variation

Click a preset row to fill the placement settings with that preset’s values.

5. Actions

Button	What it does
Preview	Spawns instances temporarily for visualization
Place	Spawns instances permanently in the level
Clear Placed	Removes all placed instances from this tool’s session
Bake to HISM	Converts placed instances to a HISM component

6. Batch

Field	What it does
Scan Spline Actors	Walks the level for all actors with USplineComponent
Spline actors list	Per-actor row: name, spline length, point count
Apply to All Splines	Runs the placement on every spline in the list

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Workflow

Single spline

1. Select a spline actor in the level, click Pick Selected Spline Actor in the tool
2. Drop a mesh into the Mesh picker
3. Pick a preset (or set Spacing manually)
4. Click Preview to see the result without committing
5. Click Place to commit

Batch across all splines

1. Click Scan Spline Actors
2. Confirm the list looks right
3. Configure the placement (one configuration applies to all)
4. Click Apply to All Splines

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Settings reference

Section-by-section defaults shown in the Interface tour above.

Settings are persisted to [Project]/Saved/EQLabs/Settings/SplineAssetPlacer.json.

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Output

• In-place actor placement — AStaticMeshActor instances along the spline
• HISM baking — Bake to HISM converts them to a single HISM component
• Undo — placement is wrapped in ScopedTransaction. Ctrl+Z reverses.

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Tips & gotchas

• Step Rotation Yaw is the secret to spiral / twisted-cable looks — at 15° per instance, you get a gentle twist; at 90°, a hard spiral
• Ground snap can fail on thin geometry — increase Ground Trace Distance if instances appear above the surface
• Sink Depth helps with foliage / debris that should appear partially buried — start at 5 cm
• Random Yaw range can be limited — use RandomYawMin / RandomYawMax (e.g., -15° to +15°) for natural variation rather than full 0–360°
• Batch mode applies the same configuration to every spline — for per-spline customization, run the tool once per spline

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Related tools

• Procedural Scattering & Placement Suite — for non-spline area scatter
• Trim & Decal Authoring Suite — for trim sheet authoring that complements modular spline placement

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