AGS 5.4 Integration and DX12 Engine Registration

Strongly recommended. This optimization works by integrating the AMD GPU Services library at version 5.4, which then allows application registration under the D3D12RHI.

Prioritize ClearRenderTargetView over clearing RT regions by drawing quads

This optimization works by eliminating the usage of rendered quads to clear a texture, and instead always calling ClearRenderTargetView().

Replace anisotropic samplers during Shadow Depths

This optimization works by identifying scenarios in which Unreal Engine will insert anisotropic samplers during the ShadowDepths pass that will not directly affect the depth output. It replaces them with Trilinear samplers instead.

Eliminate unnecessary and slow RT clears

This optimization works by identifying Render Targets which are subjected to expensive and slow clears, but are likely to subsequently have every pixel written without blending. Such clears can be skipped without penalty.

Use Compute for Histogram-based reduction during Lens Exposure

This optimization works by replacing the PostProcessHistogramReduce PS with a Compute shader implementation that leverages LDS to avoid looping texture samples.

Use one triangle for fullscreen draws

This optimization works by replacing fullscreen clears or copies which have been implemented by drawing a dual-triangle quad over an entire render target with a single triangle which also covers that entire render target (and then some).

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.

Use Compute for HZB Mip Generation

This optimization works by replacing UE4’s existing Pixel Shader HZB downsampling implementation with a tightly-threaded Compute Shader implementation.

Use Compute for combining LUTs during Post Processing

This optimization works by forcing the usage of an already-existing Compute path for LUT combination.

Improve AO Shader memory access pattern

This optimization works by making a trio of small modifications to the AmbientOcclusion PS implementation.

1. Eliminate a sample into a randomized texture, and replace it with a computed value.

2. Reorganize HZB samples to improve cache utilization.

3. Eliminate a small amount of processing if OPTIMIZATION_O1 is defined.