This tool is perfectly suited for breaking glass or stucco, as well as objects hit by bullets or arrows. The control points that are used to rule the distribution of the fragments are positioned along concentric lines around a given centre. The result is a typical look similar to a spider web. Please have take a look at the illustration below:
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The squared background area represents the object that should be fragmented. The dark blue lines are the “rays”. Additionally, there is a light blue area called “annulus” – an area between two concentric circles. Inside the annulus you can see several white circles: in the tool's interface they are called “rings”.
Voronoi
In this section you find the basic settings for the creation of the Voronoi seeds.
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The annulus is the area in which the rings are created and is defined through two parameters: “Annulus internal radius” (short, upper orange line) and “Annulus external radius” (long, lower red line).
The number of rings (white circles) is determined by the “Rings number inside annulus”.
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