Abstract: A method and related CAD system and computer readable medium. A method includes loading an object model in a CAD system, the object model including a plurality of parts each of which may contain one or more shapes which in turn are composed of multiple polygons. The method includes adding the shapes to a spatial tree, the shapes each corresponding to at least one cell, each cell corresponding to a spatial region of the object model. The method also includes, for each cell that is too complex to process within a memory space of the CAD system, subdividing the cell into a plurality of subcells using a first subdivision process. The method also includes subdividing each cell into a plurality of subcells using a multi-threaded subdivision process, and combining the subcells into the spatial tree.

Abstract: A system, method, and computer program product that accepts raw polygon geometry and view parameters from the visualization API, sorts the polygons in back-to-front order, and then supplies the sorted triangles to graphics API such as OpenGL.

Abstract: A system, method, and computer program for producing a visualization format from CAD data comprising producing a BREP model for visualization, wherein said BREP model has a topology component and a geometry component; removing a plurality of redundant control points from said geometry component; normalizing a plurality of knot vectors and a plurality of weight components from said geometry component; recognizing an analytic geometry from said geometry component; recognizing a plurality of equivalents from said geometry component; and converting said analytic geometry to said light model representation, and appropriate means and computer-readable instructions.

Abstract: A backface culling technique for clusters of polygons, as well as a method for generating efficient clusters from a set of triangle strips. The cluster backface test is directly derived from the traditional single-polygon test, and has about the same complexity. Memory requirements are 40 bytes per test. The cluster backface tests may be arranged hierarchically, with frontface tests added for symmetry. Experiments show graphics performance improvements of up to 50% in terms of number of effective polygons rendered per second.

Abstract: A control system (FIGS. 2, 3, 5, 6) and method in which multiple levels, or stages (128, 130, 132), of logical decisions are made by selectively feedforwarding output signals (356) from control modules (72) to the inputs of other modules (80), preferably through use of control modules (233) with selective feedforwarding circuits (239, 240) to logically combine during selected synchronous time slots (351) of a synchronous clock signal (FIG. 11) the result of a plurality of nonconcurrent input signals from a plurality of input devices (28, 30, 32, 34) to control an output device (26).

Abstract: A manually actuatable integrated contact module connecting to an output access module by means of a common communications link. The integrated contact module has an electrical contact, a logic circuit, a communications circuit and a communications terminal mounted on a common printed circuit board. The printed circuit board provides communication between the electrical contact and the logic circuit, between the logic circuit and the communications circuit, and between the communications circuit and the communications terminal. The printed circuit board is enclosed within a protective housing. A contact operator is slidably mounted with respect to the printed circuit board such that it is partially enclosed within the housing and movable between a first position and a second position.