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Performance

Scene weight

One number for how expensive your scene is, broken down by what is costing you — and the only performance measure that can block a publish.

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Scene weight boils a whole scene down to a single score in points, then shows you which parts of it earned those points. It's the fastest read on "is this scene too much?", and unlike the other tools on this page it has teeth: an extremely heavy scene can be refused at publish time.

Where to see it

  • Scene stats (Viewport menu) — the meter sits under the live vertex/poly/draw counts and updates as you build.
  • The publish dialog — the same meter, so you see the score at the moment it matters.

Reading the score

ScoreWhat it means
Up to 45 — lightShould run well everywhere, including older phones.
45 to 100 — moderateFine on desktops and recent phones; older or low-end devices may drop frames.
Over 100 — heavyPast the red line. Expect problems on phones and slow loads everywhere.

The meter is stacked: each band is one category, sized by what it contributes, biggest first — so the bar itself tells you what to trim. The categories are Geometry (triangles), Draw calls, Shadows, Textures, Particles, Volumetric beams, Lights, Video, Post-processing, Scene data, and Nodes, each with the count behind it.

Shadows multiply everything else A shadow-casting light re-renders your geometry an extra time, so its cost scales with the scene you already have — and a point light does it six times, once per direction. If Shadows is your biggest band, turning shadows off on one lamp (or making it a spot instead of a point) is usually the cheapest big win. Instancing is the other one: it cuts draw calls without you deleting anything.

Weight at publish time

  • Over the red line — publishing still works. It goes through with a warning naming the categories to trim.
  • Over the hard cap — publishing is refused, and a dialog shows the meter plus the heaviest categories so you know exactly what to shrink. Trim and publish again.

The cap is twice the red line (200 points) — far enough above it that only genuinely extreme scenes hit it. An already-published site that's over the cap is never bricked: you can keep republishing it as long as it doesn't get any heavier.

The AI assistant and Claude over MCP see the score too — they get a weight warning as they build, so a scene assembled by chat tends to stay in budget on its own.

Weight vs the compatibility check They answer different questions. Weight is one always-on number covering everything a frame costs — geometry, lights, effects, video — and it's what publishing enforces. The compatibility check is a deeper on-demand report that rates you per device tier and names your heaviest individual objects. Use weight while you build; run the check before you ship.
Spotted something off, or want a topic covered? Email buck.rackley@gmail.com.