Any of you know something about this:

or
quadtree
octree
per vertex ambient occlusion

BSP trees–a term widely used in industrial
real-time game engines. Without entering into details on how those trees work, you should
know that they significantly increase performance of quite heavy scenes by managing, culling,
and sorting of the geometry in binary space partition trees. The BSP technique implies that
the world geometry is sorted into tree nodes having children nodes and so on. The tree is
generated during compile time, cancelling out the need to sort all the objects in runtime.
Moreover, the system implements the PVS (potentially visible sets) technique to calculate, in
advance, which objects are occluded and therefore can be removed from the rendering during
runtime. All these features allow you, the developer, to significantly lower the restrictions
imposed on you earlier when creating big and geometry-stuffed indoor scenes.

away3d.core.partition

Partition3d is the right start point ?

I think yes:

Partition3D is the core of a space partition system. The space partition system typically subdivides the 3D scene hierarchically into a number of non-overlapping subspaces, forming a tree data structure. This is used to more efficiently perform frustum culling, potential visibility determination and collision detection.

By Away 4.1 manual…