Refactoring and renaming.
Refactoring and renaming.

Rename hasTwoTriangles to triangleSplittingNecessary. Store
firstPosition in processTriangle as local and use emittedVertexCount
to determine whether it is the first emitted position.

Christof/voly-labeller,Christof/voly-labeller,Christof/voly-labeller,Christof/voly-labeller