Arnold 7.2.1.0

Distance shader: A new distance shader that uses the distance to the nearest surface to interpolate between near and far color values.

Global light sampling: A new, more efficient sampling technique for lights is available. To enable global light sampling, set options.light_samples to a non-zero value. When enabled, the light sample settings on individual lights are ignored and the overall, global contribution of all lights together is computed using options.light_samples number of samples only. In this release, global light sampling does not apply to environment, directional lights, volumes, and GPU rendering.

More information here.

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