Methods, systems, devices and computer program products operable in a computer graphics system include constructing a hierarchical ray tracing acceleration data structure comprising a tree structure, the nodes of which are generated utilizing a bounding interval hierarchy based on defining an axis-aligned scene bounding box and two parallel planes to partition a set of objects in a sense into left objects and right objects, and matching split planes to object bounding boxes. The two planes are perpendicular to a selected one of x, y, or z-axes. Given a splitting plane, each object in an image is classified either left or right based on a left/right selection criterion, and two splitting plane values of the child modes are determined by the maximum and minimum coordinate of the left and right objects, respectively.

Systems and techniques are described for ray tracing and for the efficient construction of acceleration data structures required for fast ray tracing. A computer graphics system generates, for each pixel in an image, a pixel value that is representative of a point in a scene as recorded on an image plane of a simulated camera. The computer graphics system is configured to generate the pixel value for an image using a selected ray-tracing methodology. The selected ray-tracing methodology includes the use of a ray tree that includes at least one ray shot from the pixel into a scene along a selected direction. The ray-tracing methodology further includes calculating the intersections of rays and surfaces in the scene. An axis-aligned bounding box is defined that contains, for a given ray, the point of intersection of the ray and surface nearest the origin of the ray. The bounding box is iteratively refined until a predetermined termination criterion has been met.

In one embodiment, the present invention is directed to a data structure for representing a spatial region. The data structure comprises a hierarchical arrangement of nodes associated with a plurality of refinement levels, wherein each node of the hierarchical arrangement of nodes is a regular spatial subdivision of the spatial region or another node that is associated with a preceding refinement level. The hierarchical arrangement of nodes forms a directed acyclic graph. The hierarchical arrangement of nodes comprises at least two nodes that have respective edges that are traversed to a common child node such that the hierarchical arrangement of nodes does not comprise a repeated pattern from any two nodes of a common refinement level of the data structure.

Methods and systems provide for imposing structure onto a freeform or irregular table so that a subsequent consuming application may use the table, including presentation of the table and location of the data in the table. A generic grid structure is created having a plurality of uniformly-shaped cells such that if the generic grid is overlaid onto the irregular table, each cell within the irregular table may be located based on its position relative to the uniform cells or grids. The grid structure creates a coordinate system for defining the shape of the irregular table, for defining locations and shapes of cells comprising the irregular table and for addressing the locations of data contained in the irregular table.