3DGS Rendering Logs and Debug Tools

This page covers how to obtain diagnostic information and how to read each tool. To locate a problem by symptom, see Troubleshooting.

Viewing the Plugin Log

The plugin log has two categories:

Viewing It in the Editor

Open Window > Output Log. While investigating, type LogLCC in the filter box to find the plugin messages quickly, or run the commands below in the console to raise the log level:

log LogLCC Verbose
log LogLCC2 Verbose

The editor log file is located at:

<project directory>/Saved/Logs/<project name>.log

Viewing It in a Packaged Build

Launch a Development build with the -log parameter to bring up a console window. The log file is located at:

<package directory>/<project name>/Saved/Logs/<project name>.log

Shipping builds print no log by default, so use a Development build for investigation.

When reporting an issue, attach the complete log file of the run where the problem occurred, not just a few filtered plugin lines. Locating a problem often requires the context outside the plugin.

Render Statistics: stat XGrids

Run stat XGrids in the console, or use the Stats button under the Actions category of the Actor Details panel.

Read it together with stat unit to first judge whether the bottleneck is the 3DGS.

Count Items

The most frequently read items:

How to use it: when Current Render Splats keeps sitting close to the limit of Max Splat Num, the count limit is already cutting things off and the image detail is reduced. Either raise the limit (performance for quality), or adjust Level Factor to reduce nodes at the source.

The total data size can also be read from code, see GetSplatNumber.

Timing Items

Costs broken down by stage, used to locate which step is slow:

How to use it:

• When Splat Sort is high, the LCC pipeline can raise Sort Factor to sort less often
• When Wait Node Ready is high, data loading cannot keep up, possibly a slow disk or too few threads
• When Upload To GPU is high, the amount uploaded per frame is large, so adjust Level Factor or Max Splat Num
• When Update Collision and Get Physics Trimesh Data are high, lower Max Load Collision Distance

For the complete tuning workflow, see Performance Guide.

Memory and Video Memory Items

The percentage items correspond to the release thresholds in the project settings. Usage sitting close to Max GPU Usage Percetage For Free for long periods means resource reclamation triggers frequently, which can cause stutter.

For the video memory allocation rules and budget limits, see Rendering.

Thread Items

Node Bound Visualization

Toggle it with the Debug Node Bound button under the Actions category of the Actor Details panel, or run in the console:

r.Xgrids.DrawNodeBox 1

This draws the currently loaded nodes as wireframe boxes. The box color corresponds to the Level of the node: red, orange, yellow, green, blue, and purple progress in order, where red is the lowest Level (the highest precision) and white is the highest Level (the lowest precision).

For the node and Level concepts, see Rendering.

How to read it:

• Red boxes still rendered in the distance mean the precision is too high and performance is wasted. Raise Level Factor
• Cool-colored boxes everywhere up close mean the precision is pushed down too hard and the image looks blurry. Lower Level Factor or check Start Level
• A box count far above expectation means Max Distance may be set too large

It only works in the editor and Development builds. The matching code interface is DebugNodeBound.

Collision Visualization

Toggle it with the Show Collision button under the Actions category of the Actor Details panel, or run in the console:

r.xgrids.DrawCollision 1

This draws the wireframe of the loaded collision bodies.

How to read it:

• No wireframe at all: the data contains no collision file, or bEnableCollision is off, see Collision Prerequisites
• Wireframe only nearby: normal behavior, since collision streams in by distance and is limited by Max Load Collision Distance
• The wireframe is offset from the image content: the collision data does not match the render data, contact technical support

Enable this first when investigating line traces that miss or characters clipping through, to confirm whether collision was actually loaded. For the loading mechanism, see Collision; the code interface is ShowCollision.

Frame Rate Display

The Show FPS button under the Actions category of the Actor Details panel is equivalent to running stat fps in the console. Read it together with stat unit to see the cost distribution across threads.

Common Log Message Reference

Look up the meaning and action by message content. All of the following are the exact text the plugin outputs.

Loading

Collision

Rendering

GIS

Licensing

Proxy Mesh

What to Attach When Reporting an Issue

Collecting the items on this checklist speeds up diagnosis noticeably.

1. Plugin version and engine version. The plugin version is visible in the bottom-right corner of the plugin panel, and can also be found by searching LCC4Unreal in the Edit > Plugins window of the engine.
2. The complete log file from when the problem occurred. Provide the .log file itself, unfiltered and not just the single error line. The context around the log often contains the key information needed for diagnosis, and filtering loses those clues. For the log location, see Viewing the Plugin Log.
3. Data information. Format, approximate size (Total Splats), and whether it contains collision.
4. Reproduction steps. A minimal reproduction path starting from a new project is the most valuable.
5. Hardware environment. Graphics card model, driver version, and video memory size.
6. Project ID. Required for licensing issues; it is visible under Project Settings > Project > Description.

For contact details, see Contact Us.