Forza Horizon 4 PC Performance Review
Published: 5th October 2018 | Source: OC3D Internal Testing | Price: |
AntiAliasing - The Performance Impact
MSAA is a relatively rare graphics option in a modern PC game, with most developers opting to use a form of Temporal Anti-Aliasing, a technique which used data from previous frames to address aliasing in the game's latest frame. In this regard, Playground Games diverges from the norm, making use of MSAA in Forza Horizon 4's Xbox and PC versions.
Anti-Aliasing is a technique used to smooth otherwise jagged lines in rendered/rasterised images, reducing stair-step artefacts in images. In basic terms, Anti-Aliasing blurs the pixels at the edges where aliasing/jaggies are most noticeable, creating a clearer final image.
MSAA is well suited to racing games, where aliasing is mostly present around geometric edges, such as the body of the vehicles or in the straight lines around a racing circuit. MSAA also had none of the disadvantages of computationally cheap techniques like FXAA and TAA, both of an which present blurring artefacts, especially if the feature isn't implemented well.
Forza Horizon 4 features five Anti-Aliasing (AA) options, FXAA, MSAA 2x, MSAA 4x, MSAA 8x and none, no AA. FXAA and MSAA 2x have a similar performance impact, with MSAA 4x and MSAA 8x providing further performance reductions while offering increased aliasing.