HBAO (Ambient Occlusion)

HBAO stands for "Horizon-Based Ambient Occlusion," a rendering technique commonly used in modern video games and computer graphics to enhance the visual realism of 3D scenes. Ambient occlusion is a shading and lighting technique that simulates the soft shadows created by ambient light in the environment.

The basic idea behind HBAO is to approximate the occlusion of light in areas where objects or surfaces come close together, creating shadows in small crevices and corners, which in turn adds depth and realism to the scene. This technique focuses on occluding ambient light that is coming from the horizon, as opposed to other methods like SSAO (Screen Space Ambient Occlusion), which are screen-space based and may not capture occlusion from distant or off-screen objects.

Realism-Effects Package Reference

Properties

Name	Descriptions
`resolutionScale`	The resolution scale of the ambient occlusion.
`spp`	The samples that are taken per pixel to compute the ambient occlusion.
`distance`	Controls the radius/size of the ambient occlusion in world units.
`distanceIntensity`	Controls how fast the ambient occlusion fades away with distance in world units.
`intensity`	A purely artistic control for the intensity of the AO - runs the ao through the function pow(ao, intensity), which has the effect of darkening areas with more ambient occlusion.
`color`	The color of the ambient occlusion.
`bias`	The bias that is used for the effect in world units.
`thickness`	The thickness if the ambient occlusion effect.
`iterations`	The number of iterations of the denoising pass.
`radius`	The radius of the poisson disk.
`rings`	The rings of the poisson disk.
`lumaPhi`	Allows to adjust the influence of the luma difference in the denoising pass.
`depthPhi`	Allows to adjust the influence of the depth difference in the denoising pass.
`normalPhi`	Allows to adjust the influence of the normal difference in the denoising pass.
`samples`	The samples that are used in the poisson disk.