graphene:triangle-vertices (triangle a b c)

triangle -- a graphene:triangle-t instance
a -- a graphene:vec3-t instance for the first vertex
b -- a graphene:vec3-t instance for the second vertex
c -- a graphene:vec3-t instance for the third vertex

The value list of graphene:vec3-t instances with the vertices.

Retrieves the three vertices of the given triangle.