How to Fix Shadow Acne (Self-Shadowing Artifacts) on Models

Shadow acne is insufficient shadow bias. Tuning the bias fixes it. Here is how.

How to fix it

1. Increase the shadow bias

Shadow acne comes from surfaces shadowing themselves due to shadow-map depth precision. Increase the shadow bias to offset the comparison so surfaces do not self-shadow, removing the speckled pattern.

2. Use normal bias too

Normal bias offsets the shadow lookup along the surface normal, removing acne on angled surfaces that depth bias alone misses. Combine depth and normal bias to clean up acne across orientations.

3. Balance against peter-panning

Too much bias detaches shadows from objects (peter-panning, shadows floating away from contact). Increase bias just enough to remove acne without causing detachment, and raise shadow resolution to need less bias.

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.