How to Fix Performance from Too Many Real-Time Lights

Too many real-time lights is per-light cost multiplied. Reducing dynamic and shadowed lights fixes it. Here is how.

How to fix it

1. Bake static lights

Lights that do not move should be baked into lightmaps rather than computed in real time. Baking removes their per-frame cost entirely, leaving only the lights that genuinely need to be dynamic.

2. Limit shadow-casting lights

Shadows are the expensive part of a light. Limit how many lights cast real-time shadows, since each shadow-caster renders the scene from its view. Many use a light without shadows and look fine.

3. Reduce range, overlap, and cull

Smaller light ranges mean fewer objects affected and less overlap (overlapping lights multiply per-pixel cost). Cull lights that do not reach the visible scene so off-screen lights cost nothing.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.