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Ambient Occlusion
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In VRED the Ambient Occlusion Calculation is a
preprocess and takes place during the data
preparation. The calculated Ambient Occlusion results
will be baked on the geometries vertices. The
smoothness of the Ambient Occlusion depends on the
level of detail of a geometry. Therefore VRED offers
several ways to increase the quality on low level
geometries, like subdividing triangles and predefined
quality presets.
Ambient Occlusion is a sophisticated calculation method which simulates soft global illumination by faking
darkness perceived in corners and at mesh intersections, creases, and cracks, where light is diffused
(usually) by accumulated dirt and dust. This has the effect of darkening cracks, corners and points of
contact.
Ambient Occlusion is a specific not-physically-accurate rendering trick. It basically samples a hemisphere
around each point on the face, sees what proportion of that hemisphere is occluded by other geometry, and
shades the pixel accordingly. Its got nothing to do with light at all, its purely a rendering trick that tends
to look nice because generally in real life surfaces that are close together (like small cracks) will be darker
than surfaces that dont have anything in front of them, because of shadows, dirt, etc. The Ambient
Occlusion process though is approximating this result, its not simulating light bouncing around or going
through things. Thats why Ambient Occlusion still works when no lights are in the scene.
Important: Only selected Objects will be calculated. All other visible Objects in the scene are taken into
account.
Presets: Loads and saves Ambient Occlusion presets. Additional presets can be added or removed
Global Illumination
Shadow Quality: Defines the direct shadow quality of the Ambient Occlusion.
5 Presets are Available:
- Preview Quality
- Low Quality
- Medium Quality
- High Quality
- Highest Quality
- Ultra High Quality
Min Distance: Sets the minimum distance where objects will be taken into account for the
Ambient Occlusion calculation. This value defines total black areas where full occlusion takes
place.
Max Distance: Sets the maximum distance where objects will be taken into account or the
Ambient Occlusion calculation. This value defines total white areas where no occlusion takes
place.
This value can also be seen as the maximum expansion of the virtual hemisphere.
All numeric values represent mm as units.
Important: The total calculation time depends on the complexity of the Scene and of the
chosen Shadow Quality Preset.
Indirect Illumination
The Indirect Illumination checkbox enables an additional Calculation of indirect
light bounces which increases the quality of the final result.