UE 5.6.0: Stationary Light Issues - No Dynamic Shadows & Severe FPS Drop After Baking

Development Rendering
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Hello everyone,

I’m facing two critical issues with stationary lighting (Stationary Directional Light) in a fresh Unreal Engine 5.6.0 project using the standard First Person template. I am confident that the problem is not related to basic settings, as I have exhausted all common solutions.

Problem #1: Complete lack of dynamic shadow from the character. After baking the lighting (Build Lighting), the dynamic shadow from the character’s Skeletal Mesh completely disappears. However, if I switch the same light source to Movable, the shadow appears and works correctly. This proves the issue occurs specifically within the hybrid operational mode of a Stationary light.

Problem #2: Catastrophic FPS drop after light baking. After generating lightmaps, the performance drops by approximately 50% (e.g., from 120 FPS down to 60 FPS). This is completely counter-intuitive, as baked lighting should be cheaper. A scene with a fully Movable light source shows significantly higher FPS than the scene with a baked Stationary light.

Below is a comprehensive list of all settings and actions I have already checked to show that all standard solutions have been attempted.

List of Checked Settings and Actions:

I kindly ask not to suggest checking these items, as I have verified them multiple times.

1. Project Settings (Project Settings -> Rendering):

  • Allow Static Lighting: Enabled
  • Generate Mesh Distance Fields: Enabled (also tested with Disabled, no effect)
  • Shadow Map Method: Shadow Maps (not Virtual Shadow Maps)
  • Dynamic Global Illumination Method: None (Lumen is disabled)
  • Reflection Method: Screen Space

2. Directional Light Settings (Stationary):

  • Mobility: Stationary
  • Cast Dynamic Shadows: Enabled
  • Dynamic Shadow Distance StationaryLight: Set to a large value (20000)
  • Num Dynamic Shadow Cascades: 4
  • Distance Field Shadows: Disabled (also tested with Enabled)
  • Affects World: Enabled
  • A Lightmass Importance Volume is present and covers the entire playable area.

3. Character Blueprint Settings (BP_FirstPersonCharacter):

  • Skeletal Mesh Component (Mesh):
    • Mobility: Movable
    • Cast Shadow: Enabled
    • Affect Dynamic Indirect Lighting: Enabled
    • Single Sample Shadow from Stationary Lights: Disabled (also tested with Enabled)
  • Capsule Component:
    • Mobility: Movable
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Check Limitations and Notes in the documentation for first person rendering.

“Certain advanced first person rendering features require first person pixels to be marked with a bit in the GBuffer.”

…

“The second consequence is that Allow Static Lighting needs to be disabled in the project settings. By disabling static lighting for the project, some GBuffer bits are freed up to be used by first person rendering.”