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Global illumination - is a term used for a type of computational method used in 3D rendering. The intent of these methods is to create more realistic lighting in 3D scenes by calculating and adding the effects of indirect illumination. In other words, global illumination adds light reflected onto a surface from other surfaces in the model.
Rendering using global illumination can appear more photorealistic, but, such images are significantly more computationally intense and therefore significantly slower to create. In addition in bright, open or highly reflective environments there is always the possibility of that illumination swamping a scene and creating a washed out appearance.
Ray Trace Preview
- Shadows – OFF
- Reflections – OFF
- Refractions – OFF
- Transparency – OFF
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SamplingRate - The sampling rate can be negative to indicate under-sampling of pixels: -1 means that one sample will be computed every 2 pixels (-2 means every 4 pixels and so on.). Inversely, a positive sampling rate will correspond to an over-sampling of the pixels: 1 means 2 samples per pixel, 2 means 4 samples and so on.