Anti-aliasing
The Anti-aliasing effect softens the appearance of edges in your scene. To do this, it surrounds the edge with similar points of color. This reduces the jagged effect caused by aliasing.
The Post-processing anti-aliasing algorithms are image-based, which is useful when support for traditional multisampling is not available, such as the deferred rendering path. You can configure the rendering settings in the Quality settings window.
The Post-processing stack offers the following anti-aliasing modes:
- Fast Approximate Anti-aliasing (FXAA); a fast algorithm for mobile and platforms that don’t support motion vectors.
- Subpixel Morphological Anti-aliasing (SMAA); a high-quality but slower algorithm for mobile and platforms that don’t support motion vectors.
- Temporal Anti-aliasing (TAA); an advanced technique which requires motion vectors. Ideal for desktop and console platforms.
Each mode is set per-camera in the Post-process Layer component.
Fast Approximate Anti-aliasing (FXAA)
FXAA is the most efficient anti-aliasing technique. It's ideal for mobile and other platforms that don’t support motion vectors, which are required for Temporal Anti-aliasing.
Properties
| Property | Function |
|---|---|
| Mode | Select the type of Anti-Aliasing to use. |
| Fast Mode | Enable Fast Mode for a lower quality but faster variant of FXAA. This option is ideal for mobile platforms. |
| Keep Alpha | Enable Keep Alpha to keep the alpha channel untouched by post-processing. If Keep Alpha is disabled, Unity uses the alpha channel to store internal data used to speed up and improve visual quality. |
Performance
Enable Fast Mode if you are developing for mobile devices to get a performance boost. It will also provide a small boost for consoles. Fast Mode does not provide any extra benefits for desktop GPUs. In this case regular mode should be used for added visual quality.
Requirements
- Shader Model 3
Subpixel Morphological Anti-aliasing (SMAA)
SMAA is a higher quality anti-aliasing effect than FXAA but it's also slower. Depending on the art-style of your game it can work as well as Temporal Anti-aliasing while avoiding some of the shortcomings of this technique.
Properties
| Property | Function |
|---|---|
| Mode | Select the type of Anti-Aliasing to use. |
| Quality | Set the overall quality of the anti-aliasing filter. |
Performance
Lowering the Quality setting makes the effect run faster. Do not use SMAA on mobile platforms.
Known issues and limitations
- SMAA doesn't support AR/VR.
Requirements
- Shader Model 3
Temporal Anti-aliasing (TAA)
TAA is an 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. It is ideal for desktop and console platforms.
Properties
| Property | Function |
|---|---|
| Mode | Select the type of Anti-Aliasing to use. |
| Jitter Spread | Set the diameter (in texels) over which Unity spreads jitter samples. Smaller values result in crisper but a more aliased output. Larger values result in more stable but blurrier output. |
| Stationary Blending | Set the blend coefficient for stationary fragments. This setting controls the percentage of history sample blended into final color for fragments with minimal active motion. |
| Motion Blending | Set the blending coefficient for moving fragments. This setting controls the percentage of history sample blended into the final color for fragments with significant active motion. |
| Sharpness | Set the sharpness to alleviate the slight loss of details in high frequency regions which can be caused by TAA. |
Known issues and limitations
- Not supported on GLES2 platforms.
- Universal Render Pipeline (URP) does not support Temporal Anti-aliasing.
Requirements
- Motion vectors
- Depth texture
- Shader Model 3