Quick answer: Shadows in Godot showing “peter-panning” (gap under objects) or “shadow acne” (stippled self-shadow)? Bias settings are too high or too low respectively — tune both shadow bias and normal bias.
A character casts shadow that floats off the ground (peter-panning). Reducing bias produces shadow acne instead. The two extremes need balanced tuning.
Shadow Bias
shadow_bias offsets the depth comparison — helps avoid acne but too much creates floating shadows. Start small (e.g. 0.03 for directional lights).
Normal Bias
shadow_normal_bias offsets along surface normal — effective at hiding acne on surfaces facing the light without creating peter-panning. Often the better dial to tune first.
Shadow Atlas Size
Higher resolution shadow atlas reduces both problems — more texels per shadow caster. Project Settings → Rendering → Shadow Atlas Size.
Cascade Distances
For directional lights, distribute cascades so the close one is small (high resolution). Far cascades can use coarser bias since distant shadows hide artifacts.
Verifying
No visible acne on lit surfaces. No floating shadows beneath casters. Shadows hold detail close, soften far.
“Bias is a balance between acne and peter-panning. Tune normal bias first.”
Take a debug screenshot with high contrast lighting to test — bias problems vanish in soft lighting but bite in harsh setups.