
Our Unreal Engine performance guide
Our dedicated team of Unreal Engine engineers have been working hard to put together our recommendations
for optimizing with your Unreal Engine code base.
Performance Patches
Many of the optimization efforts that produce these patches are eventually integrated directly into a stock release of Unreal Engine. The patches presented here represent optimizations that have not been taken into Unreal Engine, and generally meet one of the following criteria:
- A similar optimization has already been applied in a subsequent release of stock Unreal Engine, and we wanted to make it available for prior versions that are still widely used.
- The optimization is still being reviewed for inclusion into stock Unreal Engine, and is provided here in the meantime.
- The optimization contains one or more AMD-specific implementations which, while they do not impact non-AMD performance, are not widely applicable enough for stock release.
Patch
Integration difficulty
4.25
4.24
4.23
Reduce memory pressure on RT volume during Translucent Lighting
This optimization works by recognizing that the pair of 64x64x64 3D textures used in the FilterTranslucentVolume pass have an alpha channel that is regularly unused. In these cases, converting those volumes from RGBA16 to R11G11B10 can yield significant performance gains with minimal side effects.
Very easy
Improve AO Shader memory access pattern
This optimization works by making a trio of small modifications to the AmbientOcclusion PS implementation.
- Eliminate a sample into a randomized texture, and replace it with a computed value.
- Reorganize HZB samples to improve cache utilization.
- Eliminate a small amount of processing if OPTIMIZATION_O1 is defined.
Very easy
Related content
Feature Patches
Patch
Integration difficulty
4.25
4.24
4.23
AMD FidelityFX – Single Pass Downsampler (SPD)
Provides an optimized solution for creating up to 12 MIP levels of a texture. This patch provides SPD optimization to the Bloom effect to accelerate texture creation. Learn more about SPD.
Easy
AMD FidelityFX – Luminance Preserving Mapper (LPM)
Integrates HDR, FreeSync™2, and wide gamut tone and gamut mapping. UE4.25+ only. Learn more about LPM.
Medium
AMD FidelityFX – Contrast Adaptive Sharpening (CAS)
Integration of FidelityFX CAS into Unreal Engine’s renderer. Learn more about CAS.
Very easy
FEMFX – Finite Element Method*
Accelerated CPU library for Finite Element Method (FEM) to compute physics for many different materials, duplicating real-world bending and breaking effects.
Hard
* – FEMFX is currently available for Unreal Engine 4.18