This geometry shader creates triangles instead of rendering a volume.
You can render fractals, particles, metaballs or even booleans between objects (with meshdist).
Unlike the volume-Solid shader you get real triangles. And therefore you can use any surface/lightmap/displacement shader like for every other poly object.
It does not use a spatial sampling technique (like marching cubes/tetrahedra), as it results in a grid-like triangulation, which require cleanups. The shader uses a surface tracking algorithm to create evenly sized triangles. The algorithm creates smaller triangles on areas of higher curvature.
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