Version: 2018.2 (switch to 2018.3b or 2017.4)
Setting up the post-processing stack
Ambient Occlusion
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Anti-aliasing

The effect descriptions on this page refer to the default effects found within the post-processing stack.

The Anti-aliasing effect offers a set of algorithms designed to prevent aliasing and give a smoother appearance to graphics. Aliasing is an effect where lines appear jagged or have a “staircase” appearance (as displayed in the left-hand image below). This can happen if the graphics output device does not have a high enough resolution to display a straight line.

Anti-aliasing reduces the prominence of these jagged lines by surrounding them with intermediate shades of color. Although this reduces the jagged appearance of the lines, it also makes them blurrier.

The Scene on the left is rendered without anti-aliasing. The Scene on the right shows the effect of the Temporal Anti-aliasing algorithm.
The Scene on the left is rendered without anti-aliasing. The Scene on the right shows the effect of the Temporal Anti-aliasing algorithm.

The Anti-aliasing algorithms are image-based. This is very useful when traditional multisampling (as used in the Editor’s Quality settings) is not properly supported, such as:

  • When using deferred rendering

  • When using HDRhigh dymanic range
    See in Glossary
    in the forward renderingA rendering path that renders each object in one or more passes, depending on lights that affect the object. Lights themselves are also treated differently by Forward Rendering, depending on their settings and intensity. More info
    See in Glossary
    path in Unity 5.5 or earlier

The algorithms supplied in the post-processing stack are:

  • Fast Approximate Anti-aliasing (FXAA)

  • Temporal Anti-aliasing (TAA)

Fast Approximate Anti-aliasing

FXAA is the cheapest technique and is recommended for mobile and other platforms that don’t support motion vectors, which are required for TAA. However it contains multiple quality presets and as such is also suitable as a fallback solution for slower desktop and console hardware.

UI for the Anti-aliasing effect when FXAA is selected
UI for the Anti-aliasing effect when FXAA is selected

Properties

Property: Function:
Preset The quality preset to be used. Provides a trade-off between performance and edge quality.

Optimisation

  • Reduce quality setting

Requirements

  • ShaderA small script that contains the mathematical calculations and algorithms for calculating the Color of each pixel rendered, based on the lighting input and the Material configuration. More info
    See in Glossary
    model 3

See the Graphics Hardware Capabilities and Emulation page for further details and a list of compliant hardware.

Temporal Anti-aliasing

Temporal Anti-aliasing is a more advanced anti-aliasing technique where frames are accumulated over time in a history buffer to be used to smooth edges more effectively. It is substantially better at smoothing edges in motion but requires motion vectors and is more expensive than FXAA. Due to this it is recommended for desktop and console platforms.

UI for the Anti-aliasing effect when TAA is selected
UI for the Anti-aliasing effect when TAA is selected

Properties

Property: Function:
Jitter - Spread The diameter (in texels) inside which jitter samples are spread. Smaller values result in crisper but more aliased output, whilst larger values result in more stable but blurrier output.
Blending - Stationary The blend coefficient for stationary fragments. Controls the percentage of history sample blended into final color for fragments with minimal active motion.
Blending - Motion The blending coefficient for moving fragments. Controls the percentage of history sample blended into the final color for fragments with significant active motion.
Sharpen TAA can induce a slight loss of details in high frequency regions. Sharpening alleviates this issue.

Restrictions

  • Unsupported in VR

Requirements

  • Motion vectors

  • Depth texture

  • Shader model 3

See the Graphics Hardware Capabilities and Emulation page for further details and a list of compliant hardware.


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Setting up the post-processing stack
Ambient Occlusion