# Ambient occlusion

<span class="label label-doc-level">Intermediate</span>
<span class="label label-doc-audience">Artist</span>

>[!Note]
>As with other depth-aware post effects, enabling ambient occlusion nullifies MSAA (multisample anti-aliasing).

**Ambient occlusion** darkens areas where light is occluded by opaque objects, such as corners and crevices. You can use it to add subtle realism to scenes.

<p>
<video autoplay loop class="responsive-video" poster="media/occlusion-on.jpg">
   <source src="media/occlusion.mp4" type="video/mp4">
</video>
</p>

## Properties

![Properties](media/ambient-occlusion-properties.png)

| Property | Function
|----------|---------
| Samples | The number of pixels sampled to determine how occluded a point is. Higher values reduce noise, but affect performance. Use with **Blur count** to find a balance between results and performance.
| Projection scale | Scales the sample radius. In most cases, `1` (no scaling) produces the most accurate result.
| Intensity | The strength of the darkening effect in occluded areas
| Sample bias | The angle at which Stride considers an area of geometry an occluder. At high values, only narrow joins and crevices are considered occluders.
| Sample radius | Use with **projection scale** to control the radius of the occlusion effect
| Blur count | The number of times the ambient occlusion image is blurred. Higher numbers reduce noise, but can produce artifacts.
| Blur scale | The blur radius in pixels
| Edge sharpness | How much the blur respects the depth differences of occluded areas. Lower numbers create more blur, but might blur unwanted areas (ie beyond occluded areas).
| Buffer size | The resolution the ambient occlusion is calculated at. The result is upscaled to the game resolution. Larger sizes produce better results but use more memory and affect performance.

## See also

* [Anti-aliasing](anti-aliasing.md)
* [Bloom](bloom.md)
* [Bright filter](bright-filter.md)
* [Color transforms](color-transforms/index.md)
* [Depth of field](depth-of-field.md)
* [Lens flare](lens-flare.md)
* [Light streaks](light-streaks.md)
* [Local reflections](local-reflections.md)