Planning Camera Paths for Gaussian Splatting Fly-Throughs

A Gaussian Splatting model rendered at a single angle is a still image. A fly-through turns it into a presentation: a smooth camera move through the scene that shows a client the space, walks a reviewer through key viewpoints, or produces frames for a video. The Scene Annotation toolincludes a camera path builder for exactly this — capture a few waypoints by orbiting, then replay them as a continuous animation.

This is a practical guide to building fly-throughs from 3DGS scenes: how waypoints work, how to plan a path that reads well, and how to get frames out for video.

How camera paths work here

A camera path is an ordered list of waypoints. Each waypoint captures the full camera state — position, orientation, and target — at a moment you choose. When you play the path back, the tool interpolates smoothly between waypoints, producing a continuous camera move through the scene.

This is different from a saved viewpoint (which is a single static camera position). A path strings viewpoints together with motion between them. You can have multiple independent paths in one scene — say, one for a hero intro and one for a detail walkthrough.

Building a path

In the annotation tool, open the Paths panel and click New Camera Path. Then:

1. Orbit / pan / zoom to the first camera position you want in the fly-through.
2. Click Capture Current View (or press C). The waypoint is added with its full camera state recorded.
3. Move the camera to the next position and capture again.
4. Repeat until the path is complete. Each waypoint's coordinates are listed in the panel.

Capturing good waypoints

The quality of a fly-through is mostly decided at capture time. A few principles:

• Start wide, end close. An establishing shot that shows the whole scene gives the viewer context; moving toward detail as the path progresses keeps attention.
• Mind the spacing. Waypoints that are close together in space produce a slow move; far-apart waypoints produce a fast one. Mixed spacing produces uneven motion that feels jarring. Try to keep consecutive waypoints at a similar distance unless you want a deliberate speed change.
• Keep camera height consistent unless you are deliberately rising or descending. Vertical wobble between waypoints reads as drift.
• Look ahead, not at the waypoints.Each waypoint's orientation should point toward where the camera is heading, so the interpolation produces forward motion rather than a pivot.

Pairing paths with calibration

If you have calibrated the scene (set scale, ground height, and north), paths respect that calibration. That means a path captured at a consistent height above the ground plane stays level, and a north-oriented path reads correctly in geographic context. For site walks through architectural or outdoor scenes, calibrate first.

Replay and export

Once a path has at least two waypoints, you can replay it: the camera steps through the waypoints with smooth interpolation, producing the fly-through animation. Use this to sanity check the move — if a transition feels abrupt, capture an intermediate waypoint to smooth it out.

To get the fly-through out of the browser:

• As part of an annotation session: paths export inside the same JSON as markers, viewpoints, and calibration. Re-importing the JSON on another machine restores the path for re-playback.
• As frames for video:play the path back and capture frames (the tool's screenshot function, or an external screen recorder) at regular intervals. Stitch the frames into a video clip in any editor.

Combining paths with annotations

Because paths live in the same workspace as markers and measurements, you can build a path that visits each annotation in turn — essentially a guided tour of the scene's points of interest. Capture a waypoint in front of each marker, in the order you want a reviewer to see them, and the resulting fly-through becomes a narrated walk through your review notes.

This is particularly useful for client review: rather than asking someone to orbit a 3D model themselves (which they may not be comfortable with), you hand them a path that shows exactly the views you want them to see, in the order you want them seen.

Planning a path that reads well

A good fly-through is a small piece of cinematography. A few planning tactics:

1. Scout first.Before capturing anything, orbit the scene manually and identify the 3–6 views that best tell the story. Note their rough order.
2. Decide on motion style. A slow, continuous forward move feels like a steadicam. Cutting between distinct viewpoints (with brief motion between each) feels like an edit. Pick one and keep it consistent.
3. Capture in order. It is much easier to build a clean path by capturing waypoints front-to-back than to reorder them after the fact.
4. Replay and revise. Watch the playback at least once. Almost every path benefits from one intermediate waypoint to smooth a transition or one removed waypoint that was causing a whip-around.
5. Keep it short.A 15–30 second fly-through almost always lands better than a two-minute one. Attention drops fast; pick the essential views and cut the rest.

What camera paths are not for

A couple of cases where a fly-through is the wrong tool:

• Letting a viewer explore freely. If the goal is for someone to orbit the model themselves, hand them a viewer link, not a path. Paths are for directed viewing.
• Inspecting detail. For close QA work, side-by-side comparison with a fixed camera is more reliable than a moving one.
• Showing every part of a large scene. Long paths through large scenes tend to feel aimless. Cut to the highlights instead.

Further reading

• Annotating and measuring 3DGS scenes — the marker and measurement workflow that paths complement.
• Compressing Gaussian Splatting models — smooth playback on the web usually needs a simplified model first.
• Full annotation tool guide and FAQ — every panel and shortcut, including the Paths panel.