Keeping Framerate Stable With GeckoLib Mobs and Shader Shadows Enabled

Understand the Cost

With the compat mod installed, GeckoLib mobs animate correctly under shader shadows — but that correctness has a price. Each animated mob is skinned once for the camera and again for the shadow pass. A village full of custom creatures therefore costs noticeably more than the same scene with shadows off.

Practical Optimizations

1. Shadow distance. This is your biggest lever. Shadows only need to look right near the player; cutting distance removes distant mobs from the shadow pass entirely.

2. Shadow resolution. Lower it before lowering distance if shadows look too soft. A slightly softer shadow is usually less noticeable than shadows popping in.

3. Entity shadow toggles. Many shaderpacks let you disable shadows for specific entity categories. If your pack separates mobs from players, you can keep player shadows crisp and cheapen mob shadows.

4. Reduce mob density. If a mod spawns GeckoLib creatures in large groups, lowering spawn rates or culling distant ones helps more than any shader setting.

5. Test in the worst case. Load your busiest area, not an empty field, before deciding your settings are stable.

What Not to Do

Do not disable the compat mod to gain performance. Without it, the shadow pass corrupts animations, and you trade a small framerate gain for visibly broken mobs. Tune the shader settings instead — that is what they are for.