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The controls in this section allow you to smooth the grid channels loaded from cache files for preview and rendering. You can use this to prevent grid artifacts on meshed grid channels such as the Liquid surface, Smoke or Temperature, to remove unwanted noise in these channels, or to get smooth motion blur by smoothing the Velocity grid channel.
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Threshold | inSmoothTemp[0], inSmoothSmoke[0], inSmoothUVW[0], inSmoothFuel[0], inSmoothVel[0] – If this value is 0, the entire grid will be smoothed evenly. The higher the threshold is raised, the less voxels will be affected and only the sharpest gradients will be smoothed. The highest value you could use here depends on the range of the values of the smoothed channel - for Smoke and Liquid it's usually in the [0,1] range, while for Velocity it could go as high as several hundred and for Temperature it could be over a thousand. If you set this value too high, no voxels will be smoothed at all.
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