Abstract: An approach to hiding memory latency in a multi-thread environment is presented. Branch Indirect and Set Link (BISL) and/or Branch Indirect and Set Link if External Data (BISLED) instructions are placed in thread code during compilation at instances that correspond to a prolonged instruction. A prolonged instruction is an instruction that instigates latency in a computer system, such as a DMA instruction. When a first thread encounters a BISL or a BISLED instruction, the first thread passes control to a second thread while the first thread's prolonged instruction executes. In turn, the computer system masks the latency of the first thread's prolonged instruction. The system can be optimized based on the memory latency by creating more threads and further dividing a register pool amongst the threads to further hide memory latency in operations that are highly memory bound.

Abstract: A program is into at least two object files: one object file for each of the supported processor environments. During compilation, code characteristics, such as data locality, computational intensity, and data parallelism, are analyzed and recorded in the object file. During run time, the code characteristics are combined with runtime considerations, such as the current load on the processors and the size of the data being processed, to arrive at an overall value. The overall value is then used to determine which of the processors will be assigned the task. The values are assigned based on the characteristics of the various processors. For example, if one processor is better at handling intensive computations against large streams of data, programs that are highly computationally intensive and process large quantities of data are weighted in favor of that processor. The corresponding object is then loaded and executed on the assigned processor.

Abstract: The present invention provides for authenticating a message. A security function is performed upon the message. The message is sent to a target. The output of the security function is sent to the target. At least one publicly known constant is sent to the target. The received message is authenticated as a function of at least a shared key, the received publicly known constants, the security function, the received message, and the output of the security function. If the output of the security function received by the target is the same as the output generated as a function of at least the received message, the received publicly known constants, the security function, and the shared key, neither the message nor the constants have been altered.

Abstract: A system and method for a DMA controller with multi-dimensional line-walking functionality is presented. A processor includes an intelligent DMA controller, which loads a line description that corresponds to a shape or line. The intelligent DMA controller moves through a memory map and retrieves data based upon the line description that includes a major step and a minor step. In turn, the intelligent DMA controller retrieves data from the shared memory without assistance from its corresponding processor. In one embodiment, the intelligent DMA controller may analyze a line using the rate of change along its minor axes in conjunction with locations where the line intersects subspaces and store array spans of contiguous memory along the line's major axis.

Abstract: The present invention renders a triangular mesh for employment in graphical displays. The triangular mesh comprises triangle-shaped graphics primitives. The triangle-shaped graphics primitives represent a subdivided triangular shape. Each triangle-shaped graphics primitive shares defined vertices with adjoining triangle-shaped graphics primitives. These shared vertices are transmitted and employed for the rendering of the triangle-shaped graphics primitives.

Abstract: A method and system for encrypting and verifying the integrity of a message using a three-phase encryption process is provided. A source having a secret master key that is shared with a target receives the message and generates a random number. The source then generates: a first set of intermediate values from the message and the random number; a second set of intermediate values from the first set of values; and a cipher text from the second set of values. At the three phases, the values are generated using the encryption function of a block cipher encryption/decryption algorithm. The random number and the cipher text are transmitted to the target, which decrypts the cipher text by reversing the encryption process. The target verifies the integrity of the message by comparing the received random number with the random number extracted from the decrypted cipher text.

Abstract: A method and an apparatus for retrieving a mipmap from memory. The method and apparatus provide an efficient method of determining the location of the desired mipmap in memory by storing the address of each row of mipmaps and calculating the offset from the start of the row to the desired mipmap. The mipmap is retrieved from memory at the location corresponding to the sum of the start address and the offset.

Abstract: The present invention renders a triangular mesh for employment in graphical displays. The triangular mesh comprises triangle-shaped graphics primitives. The triangle-shaped graphics primitives represent a subdivided triangular shape. Each triangle-shaped graphics primitive shares defined vertices with adjoining triangle-shaped graphics primitives. These shared vertices are transmitted and employed for the rendering of the triangle-shaped graphics primitives.

Abstract: A method, system, and computer program product for reducing a boundary of a subspace in a binary space partitioning tree is provided. In one embodiment a space containing an object for which an image is to be rendered and displayed to a user is divided into subspaces. The boundaries of each subspace are recalculated to remove at least a portion of the dead space from within the subspace. The recalculation is performed by analyzing the spatial extent of the object or objects within the each subspace and recalculating the boundaries of each subspace to be coextensive with the boundaries of the object or objects within the subspace.

Abstract: A method, system, and program product for creating a child node of a binary space partitioning (BSP) tree node that better approximates the size of an object to be rendered is provided. In one embodiment, a a binary space partitioning tree is created. A rendering process then determines whether either a top node or a child node in a first level of child nodes is a good approximation of the object to be rendered. If not, then the rendering process modifies the binary space partitioning tree to include a new child node having boundaries that are closer to the maximum coordinates of primitives defining the object than are the boundaries of the top node or of the child nodes in the first level of child nodes. This new child node may have a bounding volume that overlaps the bounding volumes of other child nodes in the BSP tree.

Abstract: A method and an apparatus for retrieving a mipmap from memory. The method and apparatus provide an efficient method of determining the location of the desired mipmap in memory by storing the address of each row of mipmaps and calculating the offset from the start of the row to the desired mipmap. The mipmap is retrieved from memory at the location corresponding to the sum of the start address and the offset.

Abstract: A method, apparatus, and computer implemented instructions for generating antialiased lines for display in a data processing system. Graphics data is received for display, wherein the graphics data includes primitives defining lines. A gamma correction is applied to the graphics data on a per primitive basis to form antialiased lines. The antialiased lines are displayed.

Abstract: A method, system, and computer program product for reducing a boundary of a subspace in a binary space partitioning tree is provided. In one embodiment a space containing an object for which an image is to be rendered and displayed to a user is divided into subspaces. The boundaries of each subspace are recalculated to remove at least a portion of the dead space from within the subspace. The recalculation is performed by analyzing the spatial extent of the object or objects within the each subspace and recalculating the boundaries of each subspace to be coextensive with the boundaries of the object or objects within the subspace.

Abstract: A method, system, and program product for creating a child node of a binary space partitioning (BSP) tree node that better approximates the size of an object to be rendered is provided. In one embodiment, a a binary space partitioning tree is created. A rendering process then determines whether either a top node or a child node in a first level of child nodes is a good approximation of the object to be rendered. If not, then the rendering process modifies the binary space partitioning tree to include a new child node having boundaries that are closer to the maximum coordinates of primitives defining the object than are the boundaries of the top node or of the child nodes in the first level of child nodes. This new child node may have a bounding volume that overlaps the bounding volumes of other child nodes in the BSP tree.

Abstract: Accurate display of line stipple in line segments, situated off the vertical or horizontal planes, is achieved by employing a calculated constant as a slope correction factor. The calculated constant, termed line style count, is determined utilizing the absolute length of the line segment, a ratio implementing the absolute length of the line segment, the major axis component of the line segment and fraction bits in the line counter. For each step along the major axis on a data processing system display, a constant value of 1.0 and the calculated constant, line style count, is added to a line style pointer to slope correct line stipple. A pre-computed square-root table is stored in texture memory and accessed for pre-calculated values to assist in reducing the time required to calculate accurate line style pointers.

Abstract: A method of and system for testing a graphic primitive for trivial acceptance or rejection. An initial bounding volume, such as a rectangular parallelepiped, is defined by the graphic primitive's maximum and minimum x, y, and z coordinates in an initial coordinate system. A first bounding volume is then defined by the graphic primitive's maximum and minimum x′, y′, and z′ coordinates in a first coordinate system, where the first coordinate system is transformed with respect to the initial coordinate system. Preferably this transformation comprises a 45° rotation about a common axis such as the z-axis. The initial bounding volume and the first bounding volume are then intersected to form a modified bounding volume. The vertices of the modified bounding volume are then available for use in determining whether the graphic primitive may be trivially rejected or accepted within a specified viewing volume.