Metaballs

A Metaball is the result of the algorithm, which generates a tensile surface, which generates the shape of a sphere ( is exactly one ) or a set of nested continuous beads. The algorithm was developed in the early 1980s by Jim Blinn.

A metaball is defined as a function in dimensions, ie according to the usual three dimensions. Is chosen to generate a volume of a threshold value.

Then whether the defined of metaballs body is filled at the point defined.

A typical Metaball function is

Wherein the center of the ball and indicate the point to be examined. So then the strength of the ball back at this point, the sum of the strengths of all the balls at that point is greater than the threshold value, then the body is filled therein. Since the function on the basis of the division is computationally intensive, and polynomial approximations are used.

There are many ways to render metaballs, the two most commonly used are ray casting and the marching cubes algorithm.